Sample records for walls foundations roofs

  1. Technology Solutions Case Study: Cold Climate Foundation Wall Hygrothermal Research Facility, Cloquet, Minnesota

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    2014-09-01

    This case study describes the University of Minnesota’s Cloquet Residential Research Facility (CRRF) in northern Minnesota, which features more than 2,500 ft2 of below-grade space for building systems foundation hygrothermal research. Here, the NorthernSTAR Building America Partnership team researches ways to improve the energy efficiency of the building envelope, including wall assemblies, basements, roofs, insulation, and air leakage.

  2. Urban reconciliation ecology: the potential of living roofs and walls.

    PubMed

    Francis, Robert A; Lorimer, Jamie

    2011-06-01

    Reconciling human and non-human use of urban regions to support biological conservation represents a major challenge for the 21st century. The concept of reconciliation ecology, by which the anthropogenic environment may be modified to encourage non-human use and biodiversity preservation without compromising societal utilization, potentially represents an appropriate paradigm for urban conservation given the generally poor opportunities that exist for reserve establishment and ecological restoration in urban areas. Two habitat improvement techniques with great potential for reconciliation ecology in urban areas are the installation of living roofs and walls, which have been shown to support a range of taxa at local scales. This paper evaluates the reconciliation potential of living roofs and walls, in particular highlighting both ecological and societal limitations that need to be overcome for application at the landscape scale. We further consider that successful utilization of living roofs and walls for urban reconciliation ecology will rely heavily on the participation of urban citizens, and that a 'citizen science' model is needed to facilitate public participation and support and to create an evidence base to determine their effectiveness. Living roofs and walls are just one aspect of urban reconciliation ecology, but are particularly important 'bottom-up' techniques for improving urban biodiversity that can be performed directly by the citizenry. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Retrofitted green roofs and walls and improvements in thermal comfort

    NASA Astrophysics Data System (ADS)

    Feitosa, Renato Castiglia; Wilkinson, Sara

    2017-06-01

    Increased urbanization has led to a worsening in the quality of life for many people living in large cities in respect of the urban heat island effect and increases of indoor temperatures in housing and other buildings. A solution may be to retrofit existing environments to their former conditions, with a combination of green infrastructures applied to existing walls and rooftops. Retrofitted green roofs may attenuate housing temperature. However, with tall buildings, facade areas are much larger compared to rooftop areas, the role of green walls in mitigating extreme temperatures is more pronounced. Thus, the combination of green roofs and green walls is expected to promote a better thermal performance in the building envelope. For this purpose, a modular vegetated system is adopted for covering both walls and rooftops. Rather than temperature itself, the heat index, which comprises the combined effect of temperature and relative humidity is used in the evaluation of thermal comfort in small scale experiments performed in Sydney - Australia, where identical timber framed structures prototypes (vegetated and non-vegetated) are compared. The results have shown a different understanding of thermal comfort improvement regarding heat index rather than temperature itself. The combination of green roof and walls has a valid role to play in heat index attenuation.

  4. 6. Remains Beneath Collapsed Engine House Roof, Showing Foundation Timbers ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Remains Beneath Collapsed Engine House Roof, Showing Foundation Timbers and Automobile Engine Connected to Pulley Wheel, Looking Southwest - David Renfrew Oil Rig, East side of Connoquenessing Creek, 0.4 mile North of confluence with Thorn Creek, Renfrew, Butler County, PA

  5. Evaluation of the High-Heel Roof-to-Wall Connection with Extended OSB Wall Sheathing

    Treesearch

    Andrew DeRenzis; Vladimir Kochkin; Xiping Wang

    2013-01-01

    A recently completed testing project conducted to evaluate optimized structural roof-to-wall attachment solutions demonstrated the effectiveness of wood structural panels in restraining high-heel trusses against rotation. This study was designed to further evaluate the performance of OSB wall sheathing panels extended over the high-heel truss in resisting combined...

  6. Weathering of radiocaesium contamination on urban streets, walls and roofs.

    PubMed

    Andersson, K G; Roed, J; Fogh, C L

    2002-01-01

    Recent investigations in Russia have emphasised the significance of dose contributions from contamination on urban streets and roof pavings, and, typically to a lesser extent, walls in the urban environment. The crucial factor determining the magnitude of these contributions is the retention of the contamination by the different types of urban surface. Since the Chernobyl accident, a series of long-term field studies has been carried out on urban streets, walls and roofs, to examine the weathering processes of 137Cs on the various surface types. The derived time-functions are applied to estimate resultant long-term doses to inhabitants of an urban centre. The paper highlights the effect on caesium retention of surface material characteristics.

  7. Textural break foundation wall construction modules

    DOEpatents

    Phillips, Steven J.

    1990-01-01

    Below-grade, textural-break foundation wall structures are provided for inhibiting diffusion and advection of liquids and gases into and out from a surrounding hydrogeologic environment. The foundation wall structure includes a foundation wall having an interior and exterior surface and a porous medium disposed around a portion of the exterior surface. The structure further includes a modular barrier disposed around a portion of the porous medium. The modular barrier is substantially removable from the hydrogeologic environment.

  8. 16. Power plant roof plan and wall sections, sheet 65 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    16. Power plant roof plan and wall sections, sheet 65 of 130 - Naval Air Station Fallon, Power Plant, 800 Complex, off Carson Road near intersection of Pasture & Berney Roads, Fallon, Churchill County, NV

  9. SAFETY AND SECURITY BUILDING, TRA614. FLOOR, ROOF, AND FOUNDATION PLANS. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    SAFETY AND SECURITY BUILDING, TRA-614. FLOOR, ROOF, AND FOUNDATION PLANS. ROOM FUNCTIONS. DOOR AND ROOM FINISH SCHEDULE. BLAW-KNOX 3150-814-1, 3/1950. INL INDEX NO. 531-0614-00-098-100702, REV. 6. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  10. Additional double-wall roof in single-wall, closed, convective incubators: Impact on body heat loss from premature infants and optimal adjustment of the incubator air temperature.

    PubMed

    Delanaud, Stéphane; Decima, Pauline; Pelletier, Amandine; Libert, Jean-Pierre; Stephan-Blanchard, Erwan; Bach, Véronique; Tourneux, Pierre

    2016-09-01

    Radiant heat loss is high in low-birth-weight (LBW) neonates. Double-wall or single-wall incubators with an additional double-wall roof panel that can be removed during phototherapy are used to reduce Radiant heat loss. There are no data on how the incubators should be used when this second roof panel is removed. The aim of the study was to assess the heat exchanges in LBW neonates in a single-wall incubator with and without an additional roof panel. To determine the optimal thermoneutral incubator air temperature. Influence of the additional double-wall roof was assessed by using a thermal mannequin simulating a LBW neonate. Then, we calculated the optimal incubator air temperature from a cohort of human LBW neonate in the absence of the additional roof panel. Twenty-three LBW neonates (birth weight: 750-1800g; gestational age: 28-32 weeks) were included. With the additional roof panel, R was lower but convective and evaporative skin heat losses were greater. This difference can be overcome by increasing the incubator air temperature by 0.15-0.20°C. The benefit of an additional roof panel was cancelled out by greater body heat losses through other routes. Understanding the heat transfers between the neonate and the environment is essential for optimizing incubators. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

  11. Interior detail of south wall with shed roofs showing steel ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior detail of south wall with shed roofs showing steel structure, paint room on lower right, view facing west-southwest - U.S. Naval Base, Pearl Harbor, Boat Shop, Seventh Street near Avenue E, Pearl City, Honolulu County, HI

  12. 41. Interior view of roof and wall below, looking to ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    41. Interior view of roof and wall below, looking to the east from the second floor landing at the junction of the common rafters to the raising plate, or false plate (note the false plate does not rest on the brick wall, instead is lapped over tie beams that support the floor & framing of the second level) - Kiskiack, Naval Mine Depot, State Route 238 vicinity, Yorktown, York County, VA

  13. Evaluation of the Lateral Performance of Roof Truss-to-Wall Connections in Light-Frame Wood Systems

    Treesearch

    Andrew DeRenzis; Vladimir Kochkin; Xiping Wang

    2012-01-01

    This testing program was designed to benchmark the performance of traditional roof systems and incrementally improved roof-to-wall systems with the goal of developing connection solutions that are optimized for performance and constructability. Nine full-size roof systems were constructed and tested with various levels and types of heel detailing to measure the lateral...

  14. Typical Window, Interior Wall Paint Sequence, Wall Section, and Foundation ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Typical Window, Interior Wall Paint Sequence, Wall Section, and Foundation Sections - Civilian Conservation Corps (CCC) Camp NP-5-C, Barracks No. 5, CCC Camp Historic District at Chapin Mesa, Cortez, Montezuma County, CO

  15. The impact of roofing material on building energy performance

    NASA Astrophysics Data System (ADS)

    Badiee, Ali

    The last decade has seen an increase in the efficient use of energy sources such as water, electricity, and natural gas as well as a variety of roofing materials, in the heating and cooling of both residential and commercial infrastructure. Oil costs, coal and natural gas prices remain high and unstable. All of these instabilities and increased costs have resulted in higher heating and cooling costs, and engineers are making an effort to keep them under control by using energy efficient building materials. The building envelope (that which separates the indoor and outdoor environments of a building) plays a significant role in the rate of building energy consumption. An appropriate architectural design of a building envelope can considerably lower the energy consumption during hot summers and cold winters, resulting in reduced HVAC loads. Several building components (walls, roofs, fenestration, foundations, thermal insulation, external shading devices, thermal mass, etc.) make up this essential part of a building. However, thermal insulation of a building's rooftop is the most essential part of a building envelope in that it reduces the incoming "heat flux" (defined as the amount of heat transferred per unit area per unit time from or to a surface) (Sadineni et al., 2011). Moreover, more than 60% of heat transfer occurs through the roof regardless of weather, since a roof is often the building surface that receives the largest amount of solar radiation per square annually (Suman, and Srivastava, 2009). Hence, an argument can be made that the emphasis on building energy efficiency has influenced roofing manufacturing more than any other building envelope component. This research project will address roofing energy performance as the source of nearly 60% of the building heat transfer (Suman, and Srivastava, 2009). We will also rank different roofing materials in terms of their energy performance. Other parts of the building envelope such as walls, foundation

  16. 1. AIR/MANWAY SHAFT WALL AND FAN HOUSE FOUNDATION WALL FROM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. AIR/MANWAY SHAFT WALL AND FAN HOUSE FOUNDATION WALL FROM NORTHWEST. AEROVANE FAN AT UPPER LEFT, SCAFFOLD AND LEPLEY VENTILATOR AT UPPER RIGHT. - Consolidation Coal Company Mine No. 11, Air-Manway Shaft, East side of State Route 936, Midlothian, Allegany County, MD

  17. Microbial specialists in below-grade foundation walls in Scandinavia.

    PubMed

    Nunez, M; Hammer, H

    2014-10-01

    Below-grade foundation walls are often exposed to excessive moisture by water infiltration, condensation, leakage, or lack of ventilation. Microbial growth in these structures depends largely on environmental factors, elapsed time, and the type of building materials and construction setup. The ecological preferences of Actinomycetes (Actinobacteria) and the molds Ascotricha chartarum, Myxotrichum chartarum (Ascomycota), Geomyces pannorum, and Monocillium sp. (Hyphomycetes) have been addressed based on analyses of 1764 samples collected in below-grade spaces during the period of 2001-2012. Our results show a significant correlation between these taxa and moist foundation walls as ecological niches. Substrate preference was the strongest predictor of taxa distribution within the wall, but the taxa's physiological needs, together with gradients of abiotic factors within the wall structure, also played a role. Our study describes for the first time how the wall environment affects microbial growth. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. 9. May 20, 1963 SEED BUILDING FOUNDATION WALLS Under Construction. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. May 20, 1963 SEED BUILDING FOUNDATION WALLS Under Construction. Looking southeast showing north and west walls of Machinery Shed - Tucson Plant Material Center, Machinery Shed, 3241 North Romero Road, Tucson, Pima County, AZ

  19. Shifting foundations: the mechanical cell wall and development.

    PubMed

    Braybrook, Siobhan A; Jönsson, Henrik

    2016-02-01

    The cell wall has long been acknowledged as an important physical mediator of growth in plants. Recent experimental and modelling work has brought the importance of cell wall mechanics into the forefront again. These data have challenged existing dogmas that relate cell wall structure to cell/organ growth, that uncouple elasticity from extensibility, and those which treat the cell wall as a passive and non-stressed material. Within this review we describe experiments and models which have changed the ways in which we view the mechanical cell wall, leading to new hypotheses and research avenues. It has become increasingly apparent that while we often wish to simplify our systems, we now require more complex multi-scale experiments and models in order to gain further insight into growth mechanics. We are currently experiencing an exciting and challenging shift in the foundations of our understanding of cell wall mechanics in growth and development. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  20. Airtightness Results of Roof-Only Air Sealing Strategies on 1 ½-Story Homes in Cold Climates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ojczyk, C.; Murry, T.; Mosiman, G.

    In this second study on solutions to ice dams in 1-1/2 story homes, the NorthernSTAR Building America Partnership team analyzed five test homes located in both cold and very cold climates for air leakage reduction rates following modifications by independent contractors on owner-occupied homes. These homes were chosen for testing as they are common in Minnesota and very difficult to air seal and insulate effectively. Two projects followed a roof-only Exterior Thermal Moisture Management System (ETMMS) process. One project used an interior-only approach to roof air sealing and insulation. The remaining two projects used a deep energy retrofit approach formore » whole house (foundation wall, above grade wall, roof) air leakage and heat loss reduction. All were asked to provide information regarding project goals, process, and pre and post-blower door test results. Additional air leakage reduction data was provided by several NorthernSTAR industry partners for interior-applied, roof-only modifications on 1-1/2 story homes. The data represents homes in the general market as well as homes that were part of the state of Minnesota weatherization program. A goal was to compare exterior air sealing methods with interior approaches. This pool of data enabled the team to compare air tightness data from over 220 homes using similar air seal methods.« less

  1. Double Mine Building (N) wall showing clerestory slot windows opening ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Double Mine Building (N) wall showing clerestory slot windows opening above level of main roof. Note structure is built on poured concrete foundation partly buried in hillside; view in southeast - Fort McKinley, Double Mine Building, East side of East Side Drive, approximately 125 feet south of Weymouth Way, Great Diamond Island, Portland, Cumberland County, ME

  2. Airtightness Results of Roof-Only Air Sealing Strategies on 1-1/2 Story Homes in Cold Climates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ojczyk, C.; Murry, T.; Mosiman, G.

    In this second study on solutions to ice dams in 1-1/2 story homes, five test homes located in both cold and very cold climates were analyzed for air leakage reduction rates following modifications by independent contractors on owner-occupied homes. The reason for choosing this house type was they are very common in our area and very difficult to air seal and insulate effectively. Two projects followed a roof-only Exterior Thermal Moisture Management System (ETMMS) process. One project used an interior-only approach to roof air sealing and insulation. The remaining two projects used a deep energy retrofit approach for whole housemore » (foundation wall, above grade wall, roof) air leakage and heat loss reduction. All were asked to provide information regarding project goals, process, and pre and post-blower door test results. Additional air leakage reduction data was provided by several NorthernSTAR Building America industry partners for interior-applied, roof-only modifications on 1-1/2 story homes. The data represents homes in the general market as well as homes that were part of the state of Minnesota weatherization program. A goal was to compare exterior air sealing methods with interior approaches. This pool of data enabled us to compare air tightness data from over 220 homes using similar air seal methods.« less

  3. Solar heat collection with suspended metal roofing and whole house ventilation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Maynard, T.

    1996-10-01

    A south pitched roof is employed for solar collection directly onto a roofing with chocolate brown color. The roofing is structural and is suspended over plywood decking so as to create an air space which receives input from the coolest and lowest basement air of the house interior. Air heated beneath the metal roofing is returned to a basement storage wall. Full length plenum cavities are formed into the ordinary rafter truss framing--at the knee wall and collar tie spaces. Preliminary testing of BTU gain at known air flows is acquired with a microprocessor system continuously collecting input and outputmore » temperatures at the roof collector into disk data files.« less

  4. Research on the effect of wall corrosion and rim seal on the withdrawal loss for a floating roof tank.

    PubMed

    Wang, Yongqiang; Liu, Minmin; Liu, Fang; Zhao, Chaocheng; Zhao, Dongfeng; Han, Fenglei; Liu, Chunshuang

    2018-04-25

    Storage tanks are important parts of volatile organic compound (VOC) fugitive emission sources of the petrochemical industry; the floating roof tank is the main oil storage facility at present. Based on the mechanism of withdrawal loss and the type of rim seal, octane and gasoline were taken as the research objects. A model instrument for simulating the oil loading process by the 316 stainless steel and A3 carbon steel as the test piece was designed, and the film thickness was measured by wet film thickness gauge to investigate the influence of the corrosion of the tank wall and rim seal on the withdrawal loss for floating roof tanks. It was found that withdrawal loss was directly proportional to the shell factor, and the oil thickness of the octane and gasoline increased with the strength of the wall corrosion with the same wall material and rim seal. Compared with the untreated test piece, the oil film thickness of the octane/gasoline was increased by 7.04~8.57 μm/13.14~21.93 μm and 5.59~11.49 μm/11.61~25.48 μm under the corrosion of hydrochloric acid for 32 and 75 h, respectively. The oil film thickness of octane and gasoline decreased with the increasing of the rim seal, and the oil film thickness of the octane decreased by 11.97~28.90% and 37.32~73.83% under the resilient-filled seal and the double seal, respectively. The gasoline dropped by 11.97~31.18% and 45.98~75.34% under the resilient-filled seal and the double seal, respectively. In addition, the tank surface roughness reduced the compression of the rim seal on the tank wall, and the effect of scraping decreased. The API withdrawal loss formula for a floating roof tank was recommended to take into account the effect of the rim seal to improve the accuracy of the loss evaluation. Finally, some measures of reducing the withdrawal loss were proposed.

  5. Analysis of the design and performance characteristics of pumpable roof supports

    PubMed Central

    Timothy, Batchler

    2017-01-01

    Pumpable roof supports are currently being used to provide a safe working environment for longwall mining. Because different pumpable supports are visually similar and installed fundamentally in the same manner as other supports, there is a tendency to believe they all perform the same way. However, there are several design parameters that can affect their performance, including the cementitious material properties and the bag construction practices that influence the degree of confinement provided. A full understanding of the impact of these design parameters is necessary to optimize the support application and to provide a foundation for making further improvements in the support performance. This paper evaluates the impact of various support design parameters by examining full-scale performance tests conducted using the National Institute for Occupational Safety and Health (NIOSH) Mine Roof Simulator (MRS) as part of manufacturers’ developmental and quality control testing. These tests were analyzed to identify correlations between the support design parameters and the resulting performance. Based on more than 160 tests over 7 years, quantifiable patterns were examined to assess the correlation between the support dimensions, cementitious material type, wire pitch, and single-wall vs. dual-walled bag designs to the support capacity, stiffness, load shedding events, and yield characteristics. PMID:28775910

  6. Measure Guideline. Deep Energy Enclosure Retrofit for Zero Energy Ready House Flat Roofs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Loomis, H.; Pettit, B.

    2015-05-29

    This Measure Guideline provides design and construction information for a deep energy enclosure retrofit solution of a flat roof assembly. It describes the strategies and procedures for an exterior retrofit of a flat wood-framed roof with brick masonry exterior walls using exterior and interior (framing cavity) insulation. The approach supported in this guide could also be adapted for use with flat wood-framed roofs with wood-framed exterior walls.

  7. Measure Guideline: Deep Energy Enclosure Retrofit for Zero Energy Ready House Flat Roofs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Loomis, H.; Pettit, B.

    2015-05-01

    This Measure Guideline provides design and construction information for a deep energy enclosure retrofit (DEER) solution of a flat roof assembly. It describes the strategies and procedures for an exterior retrofit of a flat, wood-framed roof with brick masonry exterior walls, using exterior and interior (framing cavity) insulation. The approach supported in this guide could also be adapted for use with flat, wood-framed roofs with wood-framed exterior walls.

  8. Study on the new technology of removing gangue and retaining roadway in complicated roof condition

    NASA Astrophysics Data System (ADS)

    Chen, Yanhao; Jiang, Cong

    2018-04-01

    This article in view of the complex roof conditions was carried on study about the new technology of removing gangue and retaining roadway, and tells a method of progressive reinforced concrete wall segment with gangue to keep the roadway, the roadway beside the support system is mainly composed of the lining, waste rock wall and the outer wall, the wall and the outer wall of concrete material width to build the strength of the progressive type filling body, waste rock wall with woven bag with waste rock assembled, paragraphs geological survey on the actual distance should be based on working face. This method relies on the interior of the gangue wall to make the pressure control and allow the roof to sink. In this paper, the finite deformation control of the roof is realized by the gangue wall and the high strength filling body. This method has the characteristics of low entry cost, good forming of roadway, high security and good stability, and can be applied to complex geological conditions such as hard roof.

  9. 29. SAME ROOMVIEW OF STONE FOUNDATION ON NORTH WALL WITH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    29. SAME ROOM-VIEW OF STONE FOUNDATION ON NORTH WALL WITH KAYAK DORY (UPPER) AND SALISBURY SKIFF (LOWER) ON DISPLAY. GRAND BANKS DORY STERN CAN BE SEEN AT LOWER LEFT. - Lowell's Boat Shop, 459 Main Street, Amesbury, Essex County, MA

  10. 40 CFR 63.1042 - Standards-Separator fixed roof.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... interface of the roof edge and the separator wall. (3) Each opening in the fixed roof shall be equipped with... closure devices shall include: organic vapor permeability; the effects of any contact with the liquid and its vapors managed in the separator; the effects of outdoor exposure to wind, moisture, and sunlight...

  11. 40 CFR 63.1042 - Standards-Separator fixed roof.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... interface of the roof edge and the separator wall. (3) Each opening in the fixed roof shall be equipped with... closure devices shall include: organic vapor permeability; the effects of any contact with the liquid and its vapors managed in the separator; the effects of outdoor exposure to wind, moisture, and sunlight...

  12. 40 CFR 63.1042 - Standards-Separator fixed roof.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... interface of the roof edge and the separator wall. (3) Each opening in the fixed roof shall be equipped with... closure devices shall include: organic vapor permeability; the effects of any contact with the liquid and its vapors managed in the separator; the effects of outdoor exposure to wind, moisture, and sunlight...

  13. 40 CFR 63.1042 - Standards-Separator fixed roof.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... interface of the roof edge and the separator wall. (3) Each opening in the fixed roof shall be equipped with... closure devices shall include: organic vapor permeability; the effects of any contact with the liquid and its vapors managed in the separator; the effects of outdoor exposure to wind, moisture, and sunlight...

  14. Coronary Sinus Activation and ECG Characteristics of Roof-Dependent Left Atrial Flutter After Pulmonary Vein Isolation.

    PubMed

    Casado Arroyo, Ruben; Laţcu, Decebal Gabriel; Maeda, Shingo; Kubala, Maciej; Santangeli, Pasquale; Garcia, Fermin Carlos; Enache, Bogdan; Eljamili, Mohammed; Hayashi, Tatsuya; Zado, Erica S; Saoudi, Nadir; Marchlinski, Francis E

    2018-06-01

    The electrocardiographic and intracardiac activation features of left atrial roof-dependent macroreentrant flutter have been incompletely characterized. Patients post-pulmonary vein (PV) isolation with roof-dependent atrial flutter based on activation and entrainment mapping were included. ECG and coronary sinus activation were compared with mitral annular (MA) flutter. The roof-dependent left atrial flutter circled the right PVs in 32 of 33 cases. Two forms of roof flutters were identified, posteroanterior, ascendant on posterior wall and descendant on anterior wall (n=24); and anteroposterior, ascendant on the anterior wall and descendent on the posterior wall (n=9). Both forms had positive large amplitude P waves in V 1 through V 2 with decreasing amplitude in V 3 through V 6 . Posteroanterior roof flutters had positive P wave in the inferior and negative P wave in leads I and aVL similar to counterclockwise MA flutter, but coronary sinus activation was simultaneous for roof and proximal to distal for counterclockwise. Anteroposterior roof flutters were similar to clockwise MA flutter with negative P in inferior leads and transition to flat or negative P in V 3 through V 6 . Coronary sinus activation time ≤39 ms identified roof versus MA flutter (sensitivity: 100% and specificity: 97%). Roof-dependent flutter around right PVs is more common than around left PVs. The ECG pattern for roof-dependent flutter around right PVs is similar to MA flutter with frontal plane axis dictated by septal activation. Roof-dependent flutter can be distinguished from MA flutter by more simultaneous rather than sequential coronary sinus activation. © 2018 American Heart Association, Inc.

  15. Roof Plans: Section "CC", Roof Plan; Roof Framing Plans: Section ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Roof Plans: Section "C-C", Roof Plan; Roof Framing Plans: Section "C-C", Section "D-D"; Roof Framing Sections: Cross Section "G-G", Cross Section "H-H" - Fort Washington, Fort Washington Light, Northeast side of Potomac River at Fort Washington Park, Fort Washington, Prince George's County, MD

  16. PROCESS WATER BUILDING, TRA605. FLOOR AND ROOF PLANS FOR SECOND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    PROCESS WATER BUILDING, TRA-605. FLOOR AND ROOF PLANS FOR SECOND FLOOR. DETAILS OF CONCRETE ROOF SLABS. FLASH EVAPORATOR SUPPORTS AND PIPE OPENINGS TO TANKS BELOW. NOTE SPECIFIES THAT EQUIPMENT IS TO BE INSTALLED BEFORE ERECTION OF ROOF AND WALLS. BLAW-KNOX 3150-805-4, 1/1951. INL INDEX NO. 531-0605-62-098-100660, REV. 2. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  17. Hydraulic Performance of Shallow Foundations for the Support of Vertical-Wall Bridge Abutments

    DOT National Transportation Integrated Search

    2017-02-01

    This study combined abutment flume experiments with numerical modeling using computational fluid dynamics (CFD) to investigate flow fields and scour at vertical-wall abutments with shallow foundations. The focus was situations dominated by flow contr...

  18. Prolong Your Roof's Performance: Roof Asset Management.

    ERIC Educational Resources Information Center

    Teitsma, Jerry

    2001-01-01

    Discusses the roof asset management process for maintaining a roof system's integrity and value in a cost-effective manner. Included is a breakdown of roofing surface characteristics for multiply and single ply roofing systems. (GR)

  19. COOL ROOF COATINGS INCORPORATING GLASS HOLLOW MICROSPHERES

    EPA Science Inventory

    Solar Gain is in part responsible for up to 56% of energy consumed by cooling systems in residential buildings. By reflecting and scattering radiant energy from the sun, the surface temperature of exterior walls and roofs can be greatly reduced. Previous studies have indicated...

  20. Molded Concrete Center Mine Wall

    NASA Technical Reports Server (NTRS)

    Lewis, E. V.

    1987-01-01

    Proposed semiautomatic system forms concrete-foam wall along middle of coal-mine passage. Wall helps support roof and divides passage into two conduits needed for ventilation of coal face. Mobile mold and concrete-foam generator form sections of wall in place.

  1. System for monitoring of green roof performance: use of weighing roof segment and non-invasive visualization

    NASA Astrophysics Data System (ADS)

    Jelinkova, Vladmira; Dohnal, Michal; Picek, Tomas; Sacha, Jan

    2015-04-01

    Understanding the performance of technogenic substrates for green roofs is a significant task in the framework of sustainable urban planning and water/energy management. The potential retention and detention of the anthropogenic, light weight soil systems and their temporal soil structure changes are of major importance. A green roof test segment was built to investigate the benefits of such anthropogenic systems. Adaptable low-cost system allows long-term monitoring of preferred characteristics. Temperature and water balance measurements complemented with meteorological observations and knowledge of physical properties of the substrates provide basis for detailed analysis of thermal and hydrological regime in green roof systems. The first results confirmed the benefits of green roof systems. The reduction of temperature fluctuations as well as rainfall runoff was significant. Depending on numerous factors such substrate material or vegetation cover the test green roof suppressed the roof temperature amplitude for the period analyzed. The ability to completely prevent (light rainfall events) or reduce and delay (medium and heavy rainfall events) the peak runoff was also analyzed. Special attention is being paid to the assessment of soil structural properties related to possible aggregation/disaggregation, root growth, weather conditions and associated structural changes using non-invasive imaging method. X-ray computed microtomography of undisturbed soil samples (taken from experimental segments) is used for description of pore space geometry, evaluation of surface to volume ratio, additionally for description of cracks and macropores as a product of soil flora and fauna activity. The information from computed tomography imaging will be used for numerical modeling of water flow in variable saturated porous media. The research was realized as a part of the University Centre for Energy Efficient Buildings supported by the EU and with financial support from the Czech

  2. [A review of green roof performance towards management of roof runoff].

    PubMed

    Chen, Xiao-ping; Huang, Pei; Zhou, Zhi-xiang; Gao, Chi

    2015-08-01

    Green roof has a significant influence on reducing runoff volume, delaying runoff-yielding time, reducing the peak flow and improving runoff quality. This paper addressed the related research around the world and concluded from several aspects, i.e., the definition of green roof of different types, the mechanism how green roof manages runoff quantity and quality, the ability how green roof controls roof runoff, and the influence factors of green roof toward runoff quantity and quality. Afterwards, there was a need for more future work on research of green roof toward roof runoff, i.e., vegetation selection of green roof, efficient construction model selection of green roof, the regulating characteristics of green roof on roof runoff, the value assessment of green roof on roof runoff, analysis of source-sink function of green roof on the water pollutants of roof runoff and the research on the mitigation measures of roof runoff pollution. This paper provided a guideline to develop green roofs aiming to regulating roof runoff.

  3. Department of the Navy. FY 1994/FY 1995 Biennial Budget Estimates. Military Construction Program. FY 1994

    DTIC Science & Technology

    1992-01-01

    3 are severely deteriorated. The concrete deck and supporting wood -pile structure are nearing the end of their life cycle. Both piers are to be...PROPOSED CONSTRUCTION One-story building with concrete foundation walls, load bearing masonry walls, and concrete floors; roof with wood truss framing...concrete building addition; concrete foundation and slab on grade; wood truss roof; 750 KVA. 3 phase transformer; utilities; concrete and storm drain. 11

  4. View of North End of Oxide Building Interior Including Roof ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of North End of Oxide Building Interior Including Roof and Wall Juncture and Crane Trolley - Hematite Fuel Fabrication Facility, Oxide Building & Oxide Loading Dock, 3300 State Road P, Festus, Jefferson County, MO

  5. Wind Tunnel Tests for Wind Pressure Distribution on Gable Roof Buildings

    PubMed Central

    2013-01-01

    Gable roof buildings are widely used in industrial buildings. Based on wind tunnel tests with rigid models, wind pressure distributions on gable roof buildings with different aspect ratios were measured simultaneously. Some characteristics of the measured wind pressure field on the surfaces of the models were analyzed, including mean wind pressure, fluctuating wind pressure, peak negative wind pressure, and characteristics of proper orthogonal decomposition results of the measured wind pressure field. The results show that extremely high local suctions often occur in the leading edges of longitudinal wall and windward roof, roof corner, and roof ridge which are the severe damaged locations under strong wind. The aspect ratio of building has a certain effect on the mean wind pressure coefficients, and the effect relates to wind attack angle. Compared with experimental results, the region division of roof corner and roof ridge from AIJ2004 is more reasonable than those from CECS102:2002 and MBMA2006.The contributions of the first several eigenvectors to the overall wind pressure distributions become much bigger. The investigation can offer some basic understanding for estimating wind load distribution on gable roof buildings and facilitate wind-resistant design of cladding components and their connections considering wind load path. PMID:24082851

  6. Wind tunnel tests for wind pressure distribution on gable roof buildings.

    PubMed

    Jing, Xiao-kun; Li, Yuan-qi

    2013-01-01

    Gable roof buildings are widely used in industrial buildings. Based on wind tunnel tests with rigid models, wind pressure distributions on gable roof buildings with different aspect ratios were measured simultaneously. Some characteristics of the measured wind pressure field on the surfaces of the models were analyzed, including mean wind pressure, fluctuating wind pressure, peak negative wind pressure, and characteristics of proper orthogonal decomposition results of the measured wind pressure field. The results show that extremely high local suctions often occur in the leading edges of longitudinal wall and windward roof, roof corner, and roof ridge which are the severe damaged locations under strong wind. The aspect ratio of building has a certain effect on the mean wind pressure coefficients, and the effect relates to wind attack angle. Compared with experimental results, the region division of roof corner and roof ridge from AIJ2004 is more reasonable than those from CECS102:2002 and MBMA2006.The contributions of the first several eigenvectors to the overall wind pressure distributions become much bigger. The investigation can offer some basic understanding for estimating wind load distribution on gable roof buildings and facilitate wind-resistant design of cladding components and their connections considering wind load path.

  7. Technical - Economic Research for Passive Buildings

    NASA Astrophysics Data System (ADS)

    Miniotaite, Ruta

    2017-10-01

    A newly constructed passive house must save 80 % of heat resources; otherwise it is not a passive house. The heating energy demand of a passive building is less than 15 kWh/m2 per year. However, a passive house is something more than just an energy-saving house. This concept involves sustainable, high-quality, valuable, healthy and durable construction. Features of a passive house: high insulation of envelope components, high-quality windows, good tightness of the building, regenerative ventilation system and elimination of thermal bridges. The Energy Performance of Buildings Directive (EPBD) 61 requires all new public buildings to become near-zero energy buildings by 2019 and will be extended to all new buildings by 2021. This concept involves sustainable, high-quality, valuable, healthy and durable construction. Foundation, walls and roofs are the most essential elements of a house. The type of foundation for a private house is selected considering many factors. The article examines technological and structural solutions for passive buildings foundation, walls and roofs. The technical-economic comparison of the main structures of a passive house revealed that it is cheaper to install an adequately designed concrete slab foundation than to build strip or pile foundation and the floor separately. Timber stud walls are the cheapest wall option for a passive house and 45-51% cheaper compared to other options. The comparison of roofs and ceilings showed that insulation of the ceiling is 25% more efficient than insulation of the roof. The comparison of the main envelope elements efficiency by multiple-criteria evaluation methods showed that it is economically feasible to install concrete slab on ground foundation, stud walls with sheet cladding and a pitched roof with insulated ceiling.

  8. 31. DETAILMETAL ROOF TRUSS OF THE NORTH WING OF BUILDING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    31. DETAIL--METAL ROOF TRUSS OF THE NORTH WING OF BUILDING 36 LOOKING WEST TO THE WALL PARTITIONING BUILDING 36 AND BUILDING 33. - Navy Yard, Ordnance Building, Intersection of Paulding & Kennon Streets, Washington, District of Columbia, DC

  9. 9. Oblique view from liftbed truck, showing deteriorated slate roof ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. Oblique view from lift-bed truck, showing deteriorated slate roof and chimney, bicycle lockers placed against southeast wall; view to north, 90mm lens. - Southern Pacific Depot, 559 El Camino Real, San Carlos, San Mateo County, CA

  10. Out-of-plane (SH) soil-structure interaction: a shear wall with rigid and flexible ring foundation

    NASA Astrophysics Data System (ADS)

    Le, Thang; Lee, Vincent W.; Luo, Hao

    2016-02-01

    Soil-structure interaction (SSI) of a building and shear wall above a foundation in an elastic half-space has long been an important research subject for earthquake engineers and strong-motion seismologists. Numerous papers have been published since the early 1970s; however, very few of these papers have analytic closed-form solutions available. The soil-structure interaction problem is one of the most classic problems connecting the two disciplines of earthquake engineering and civil engineering. The interaction effect represents the mechanism of energy transfer and dissipation among the elements of the dynamic system, namely the soil subgrade, foundation, and superstructure. This interaction effect is important across many structure, foundation, and subgrade types but is most pronounced when a rigid superstructure is founded on a relatively soft lower foundation and subgrade. This effect may only be ignored when the subgrade is much harder than a flexible superstructure: for instance a flexible moment frame superstructure founded on a thin compacted soil layer on top of very stiff bedrock below. This paper will study the interaction effect of the subgrade and the superstructure. The analytical solution of the interaction of a shear wall, flexible-rigid foundation, and an elastic half-space is derived for incident SH waves with various angles of incidence. It found that the flexible ring (soft layer) cannot be used as an isolation mechanism to decouple a superstructure from its substructure resting on a shaking half-space.

  11. Roofing Source File.

    ERIC Educational Resources Information Center

    American School & University, 1994

    1994-01-01

    Presents a resource guide for identifying, selecting, and specifying educational roofing systems. Explores the various types of roofing systems considered for most schools and describes how to select a roofing contractor and consultant. A roofing retrofit check list and roofing specification chart are provided. (GR)

  12. 40 CFR 63.902 - Standards-Tank fixed roof.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... section joints or between the interface of the roof edge and the tank wall. (3) Each opening in the fixed... closure devices shall include: organic vapor permeability, the effects of any contact with the liquid or its vapors managed in the tank; the effects of outdoor exposure to wind, moisture, and sunlight; and...

  13. 40 CFR 63.902 - Standards-Tank fixed roof.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... section joints or between the interface of the roof edge and the tank wall. (3) Each opening in the fixed... closure devices shall include: organic vapor permeability, the effects of any contact with the liquid or its vapors managed in the tank; the effects of outdoor exposure to wind, moisture, and sunlight; and...

  14. 40 CFR 63.902 - Standards-Tank fixed roof.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... section joints or between the interface of the roof edge and the tank wall. (3) Each opening in the fixed... closure devices shall include: organic vapor permeability, the effects of any contact with the liquid or its vapors managed in the tank; the effects of outdoor exposure to wind, moisture, and sunlight; and...

  15. 40 CFR 63.902 - Standards-Tank fixed roof.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... section joints or between the interface of the roof edge and the tank wall. (3) Each opening in the fixed... closure devices shall include: organic vapor permeability, the effects of any contact with the liquid or its vapors managed in the tank; the effects of outdoor exposure to wind, moisture, and sunlight; and...

  16. An analysis of roof bolter fatalities and injuries in U.S. mining

    PubMed Central

    Sammarco, J.J.; Podlesny, A.; Rubinstein, E.N.; Demich, B.

    2017-01-01

    Roof bolting typically follows the extraction of a commodity to help keep the roof from collapsing. During 2004 to 2013, roof bolter operators had the highest number of machinery-related injuries, accounting for 64.7 percent, at underground coal mines. This paper analyzes U.S. roof bolter fatal and nonfatal lost-time injury data at underground work locations for all commodities from 2004 through 2013 and determines risk indices for six roof bolting tasks. For fatal and nonfatal incidences combined, the roof bolting tasks in order of the highest to lowest risk index were bolting, handling of materials, setting the temporary roof support (TRS), drilling, tramming, and traversing. For fatalities, the roof bolting tasks in order of the highest to lowest risk index were handling of materials, setting the TRS, bolting, drilling, traversing, and tramming. Age was found to be a significant factor. Severity of injury, indicated by days lost, was found to increase with increasing age as well as with increasing experience, largely due to the confounding of age and experience. The operation of the roof bolting machine used in underground mining should be a research priority given the high frequency and severity of incidents. The results also suggest that temporal factors may exist, so additional research is warranted to better understand these factors and potentially develop interventions. This research provides a data-driven foundation from which future research can be conducted for safety interventions to reduce the frequency and severity of incidences involving the roof bolter activities of bolting, handling of materials, and setting the TRS. PMID:28845099

  17. Geotechnical LFRD calculations of settlement and bearing capacity of GDOT shallow bridge foundations and retaining walls.

    DOT National Transportation Integrated Search

    2016-08-09

    The AASHTO codes for Load Resistance Factored Design (LRFD) regarding shallow bridge foundations : and walls have been implemented into a set of spreadsheet algorithms to facilitate the calculations of bearing : capacity and footing settlements on na...

  18. Understanding Roofing Systems.

    ERIC Educational Resources Information Center

    Michelsen, Ted

    2001-01-01

    Reviews the various types of multi- and single-ply roofing commonly used today in educational facilities. Roofing types described involve built-up systems, modified bitumen systems; ethylene propylene diene terpolymer roofs; and roofs of thermoplastic, metal, and foam. A description of the Roofing Industry Educational Institute is included. (GR)

  19. Meteorological Station, interior with collapsed roof showing remnant wooden equipment ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Meteorological Station, interior with collapsed roof showing remnant wooden equipment switch box on east wall; view southeast - Fort McKinley, Meteorological Station, East side of Weymouth Way, approximately 225 feet south of Cove Side Drive, Great Diamond Island, Portland, Cumberland County, ME

  20. Effects of building roof greening on air quality in street canyons

    NASA Astrophysics Data System (ADS)

    Baik, Jong-Jin; Kwak, Kyung-Hwan; Park, Seung-Bu; Ryu, Young-Hee

    2012-12-01

    Building roof greening is a successful strategy for improving urban thermal environment. It is of theoretical interest and practical importance to study the effects of building roof greening on urban air quality in a systematic and quantitative way. In this study, we examine the effects of building roof greening on air quality in street canyons using a computational fluid dynamics (CFD) model that includes the thermodynamic energy equation and the transport equation of passive, non-reactive pollutants. For simplicity, building roof greening is represented by specified cooling. Results for a simple building configuration with a street canyon aspect ratio of one show that the cool air produced due to building roof greening flows into the street canyon, giving rise to strengthened street canyon flow. The strengthened street canyon flow enhances pollutant dispersion near the road, which decreases pollutant concentration there. Thus, building roof greening improves air quality near the road. The degree of air quality improvement near the road increases as the cooling intensity increases. In the middle region of the street canyon, the air quality can worsen when the cooling intensity is not too strong. Results for a real urban morphology also show that building roof greening improves air quality near roads. The degree of air quality improvement near roads due to building roof greening depends on the ambient wind direction. These findings provide a theoretical foundation for constructing green roofs for the purpose of improving air quality near roads or at a pedestrian level as well as urban thermal environment. Further studies using a CFD model coupled with a photochemistry model and a surface energy balance model are required to evaluate the effects of building roof greening on air quality in street canyons in a more realistic framework.

  1. Roofing Materials Assessment: Investigation of Five Metals in Runoff from Roofing Materials.

    PubMed

    Winters, Nancy; Granuke, Kyle; McCall, Melissa

    2015-09-01

    To assess the contribution of five toxic metals from new roofing materials to stormwater, runoff was collected from 14 types of roofing materials and controls during 20 rain events and analyzed for metals. Many of the new roofing materials evaluated did not show elevated metals concentrations in the runoff. Runoff from several other roofing materials was significantly higher than the controls for arsenic, copper, and zinc. Notably, treated wood shakes released arsenic and copper, copper roofing released copper, PVC roofing released arsenic, and Zincalume® and EPDM roofing released zinc. For the runoff from some of the roofing materials, metals concentrations decreased significantly over an approximately one-year period of aging. Metals concentrations in runoff were demonstrated to depend on a number of factors, such as roofing materials, age of the materials, and climatic conditions. Thus, application of runoff concentrations from roofing materials to estimate basin-wide releases should be undertaken cautiously.

  2. Field Testing of an Unvented Roof with Fibrous Insulation, Tiles and Vapor Diffusion Venting

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ueno, K.; Lstiburek, J. W.

    This research is a test implementation of an unvented tile roof assembly in a hot-humid climate (Orlando, FL; Zone 2A), insulated with air permeable insulation (netted and blown fiberglass). Given the localized moisture accumulation and failures seen in previous unvented roof field work, it was theorized that a 'diffusion vent' (water vapor open, but air barrier 'closed') at the highest points in the roof assembly might allow for the wintertime release of moisture, to safe levels. The 'diffusion vent' is an open slot at the ridge and hips, covered with a water-resistant but vapor open (500+ perm) air barrier membrane.more » As a control comparison, one portion of the roof was constructed as a typical unvented roof (self-adhered membrane at ridge). The data collected to date indicate that the diffusion vent roof shows greater moisture safety than the conventional, unvented roof design. The unvented roof had extended winter periods of 95-100% RH, and wafer (wood surrogate RH sensor) measurements indicating possible condensation; high moisture levels were concentrated at the roof ridge. In contrast, the diffusion vent roofs had drier conditions, with most peak MCs (sheathing) below 20%. In the spring, as outdoor temperatures warmed, all roofs dried well into the safe range (10% MC or less). Some roof-wall interfaces showed moderately high MCs; this might be due to moisture accumulation at the highest point in the lower attic, and/or shading of the roof by the adjacent second story. Monitoring will be continued at least through spring 2016 (another winter and spring).« less

  3. The green roof dilemma - discussion of Francis and Lorimer (2011).

    PubMed

    Henry, Alexandre; Frascaria-Lacoste, Nathalie

    2012-08-15

    Urban ecosystems are the most complex mosaics of vegetative land cover that can be found. In a recent paper, Francis and Lorimer (2011) evaluated the reconciliation potential of living roofs and walls. For these authors, these two techniques for habitat improvement have strong potential for urban reconciliation ecology. However they have some ecological and societal limitations such as the physical extreme environmental characteristics, the monetary investment and the cultural perceptions of urban nature. We are interested in their results and support their conclusions. However, for a considerable time, green roofs have been designed to provide urban greenery for buildings and the green roof market has only focused on extensive roof at a restricted scale within cities. Thus, we have strong doubts about the relevance of their use as possible integrated elements of the network. Furthermore, without dynamic progress in research and the implementation of well-thought-out policies, what will be the real capital gain from green roofs with respect to land-use complementation in cities? If we agree with Francis and Lorimer (2011) considering that urban reconciliation ecology between nature and citizens is a current major challenge, then "adaptive collaborative management" is a fundamental requirement. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. 5. Roof Truss Above Service Area, Roof Truss Above Ward, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Roof Truss Above Service Area, Roof Truss Above Ward, Roof Framing Axonometric - National Home for Disabled Volunteer Soldiers - Battle Mountain Sanitarium, Ward 4, 500 North Fifth Street, Hot Springs, Fall River County, SD

  5. Roofing: Workbook and Tests. Common Roofing and Waterproofing Materials and Equipment.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento. Bureau of Publications.

    This workbook on materials and equipment is one of a series of nine individual units of instruction for roofing apprenticeship classes in California. The workbook covers eight topics: production of bitumens and asphaltic roofing materials; built-up roofing materials and adhesives; asphaltic products and rigid roofing materials; elastomeric and…

  6. Common Roofing and Waterproofing Materials and Equipment. Roofing Workbook and Tests.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento. Bureau of Publications.

    This publication on common roofing and waterproofing materials and equipment is one of a series of units of instruction for roofing apprenticeship classes. The workbook portion is divided into eight topics: production of bitumens and asphalt roofing materials, built-up materials and adhesives, asphalt products and rigid roofing materials,…

  7. PERFORMANCE OF AN EARTHQUAKE EXCITED ROOF DIAPHRAGM.

    USGS Publications Warehouse

    Celebi, M.; Brady, G.; Safak, E.; Converse, A.; ,

    1986-01-01

    The objective of this paper is to study the earthquake performance of the roof diaphragm of the West Valley College gymnasium in Saratoga, California through a complete set of acceleration records obtained during the 24 April 1984 Morgan Hill Earthquake (M equals 6. 1). The roof diaphragm of the 112 ft. multiplied by 144 ft. rectangular, symmetric gymnasium consists of 3/8 in. plywood over tongue-and-groove sheathing attached to steel trusses supported by reinforced concrete columns and walls. Three sensors placed in the direction of each of the axes of the diaphragm facilitate the evaluation of in-plane deformation of the diaphragm. Other sensors placed at ground level measure vertical and horizontal motion of the building floor, and consequently allow the calculation of the relative motion of the diaphragm with respect to the ground level.

  8. [Distribution form of nutrients in roof runoff].

    PubMed

    Wang, Biao; Li, Tian; Meng, Ying-Ying; Ren, Zhong-Jia; Cao, Bing-Yin

    2008-11-01

    6 rainfall-runoff events were examined from a concrete roof by a traffic artery in Shanghai to characterize the particle-bound and dissolved nutrients in roof runoff and to get more knowledge about roof runoff pollutants and lay the theoretic foundation for the selection of roof runoff purification method. Results indicated that event mean concentration (EMC) of TN ranges between 4.208 mg/L and 8.427 mg/L compared to 0.078-0.185 mg/L for TP. DN and PP are respectively the primary forms of TN and TP. During the runoff, the number ratio of small particles is gradually increased. The dynamic behavior of TP is similar to TSS, but the TN-TSS relationship in the course of runoff is not obvious. The increase of both PN/TSS and the number ration of small particles showed that nitrogen (microgramme per gram particle weight) attached to small particles is more than large particles. Regression analysis between TSS and TP & PP of samples in the early 10 min of runoff results in a high R2, but the relationship between TSS and TP & PP of samples in the entire runoff is not as close as the early 10 min, which reflects that the phosphorus quantity attached to the particle changes from the perspective of the entire course of runoff. First flush of TP is stronger than TN because the load discharge of dissolved nutrients is more stable than particle nutrients. In addition, more nitrogen absorbed by the unit mass small particles to a certain degree weakens the first flush of TN.

  9. Numerical Investigation of the Effect of the Location of Critical Rock Block Fracture on Crack Evolution in a Gob-side Filling Wall

    NASA Astrophysics Data System (ADS)

    Li, Xuehua; Ju, Minghe; Yao, Qiangling; Zhou, Jian; Chong, Zhaohui

    2016-03-01

    Generation, propagation, and coalescence of the shear and tensile cracks in the gob-side filling wall are significantly affected by the location of the fracture of the critical rock block. The Universal Discrete Element Code software was used to investigate crack evolution characteristics in a gob-side filling wall and the parameter calibration process for various strata and the filling wall was clearly illustrated. The cracks in both the filling wall and the coal wall propagate inward in a V-shape pattern with dominant shear cracks generated initially. As the distance between the fracture and the filling wall decreases, the number of cracks in the filling wall decreases, and the stability of the filling wall gradually improves; thus, by splitting the roof rock at the optimal location, the filling wall can be maintained in a stable state. Additionally, we conducted a sensitivity analysis that demonstrated that the higher the coal seam strength, the fewer cracks occur in both the filling wall and the coal wall, and the less failure they experience. With the main roof fracturing into a cantilever structure, the higher the immediate roof strength, the fewer cracks are in the filling wall. With the critical rock block fracturing above the roadway, an optimal strength of the immediate roof can be found that will stabilize the filling wall. This study presents a theoretical investigation into stabilization of the filling wall, demonstrating the significance of pre-splitting the roof rock at a desirable location.

  10. 25. Detail, roof at junction of main roof and tower ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    25. Detail, roof at junction of main roof and tower skirt roof; note condition of slates, subroof, missing gutter, lead pipe gutter outlet; view to northwest from lift-bed truck, 135mm lens. - Southern Pacific Depot, 559 El Camino Real, San Carlos, San Mateo County, CA

  11. 24. Roof detail from liftbed truck, showing pan roof above ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. Roof detail from lift-bed truck, showing pan roof above breezeway, with sawn redwood trim, tube-type drains; note missing rain gutter at roof edge, deteriorated condition of slates; view to south, 90mm lens. - Southern Pacific Depot, 559 El Camino Real, San Carlos, San Mateo County, CA

  12. Thermal and water regime of green roof segments filled with Technosol

    NASA Astrophysics Data System (ADS)

    Jelínková, Vladimíra; Šácha, Jan; Dohnal, Michal; Skala, Vojtěch

    2016-04-01

    Artificial soil systems and structures comprise appreciable part of the urban areas and are considered to be perspective for number of reasons. One of the most important lies in contribution of green roofs and facades to the heat island effect mitigation, air quality improvement, storm water reduction, etc. The aim of the presented study is to evaluate thermal and water regime of the anthropogenic soil systems during the first months of the construction life cycle. Green roof test segments filled with two different anthropogenic soils were built to investigate the benefits of such systems in the temperate climate. Temperature and water balance measurements complemented with meteorological observations and knowledge of physical properties of the soil substrates provided basis for detailed analysis of thermal and hydrological regime. Water balance of green roof segments was calculated for available vegetation seasons and individual rainfall events. On the basis of an analysis of individual rainfall events rainfall-runoff dependency was found for green roof segments. The difference between measured actual evapotranspiration and calculated potential evapotranspiration was discussed on period with contrasting conditions in terms of the moisture stress. Thermal characteristics of soil substrates resulted in highly contrasting diurnal variation of soils temperatures. Green roof systems under study were able to reduce heat load of the roof construction when comparing with a concrete roof construction. Similarly, received rainfall was significantly reduced. The extent of the rainfall reduction mainly depends on soil, vegetation status and experienced weather patterns. The research was realized as a part of the University Centre for Energy Efficient Buildings supported by the EU and with financial support from the Czech Science Foundation under project number 14-10455P.

  13. Raising the Roof.

    ERIC Educational Resources Information Center

    Savage, John

    2000-01-01

    Discusses how the use of metal standing-seam roofs can help conserve energy, and with proper maintenance, be long-lasting. An example is given of one high school's replacement of their leaking roof with a metal standing-seam roof. (GR)

  14. Building America Case Study: Field Testing an Unvented Roof with Fibrous Insulation and Tiles, Orlando, Florida

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    This research is a test implementation of an unvented tile roof assembly in a hot-humid climate (Orlando, FL; Zone 2A), insulated with air permeable insulation (netted and blown fiberglass). Given the localized moisture accumulation and failures seen in previous unvented roof field work, it was theorized that a 'diffusion vent' (water vapor open, but air barrier 'closed') at the highest points in the roof assembly might allow for the wintertime release of moisture, to safe levels. The 'diffusion vent' is an open slot at the ridge and hips, covered with a water-resistant but vapor open (500+ perm) air barrier membrane.more » As a control comparison, one portion of the roof was constructed as a typical unvented roof (self-adhered membrane at ridge). The data collected to date indicate that the diffusion vent roof shows greater moisture safety than the conventional, unvented roof design. The unvented roof had extended winter periods of 95-100% RH, and wafer (wood surrogate RH sensor) measurements indicating possible condensation; high moisture levels were concentrated at the roof ridge. In contrast, the diffusion vent roofs had drier conditions, with most peak MCs (sheathing) below 20%. In the spring, as outdoor temperatures warmed, all roofs dried well into the safe range (10% MC or less). Some roof-wall interfaces showed moderately high MCs; this might be due to moisture accumulation at the highest point in the lower attic, and/or shading of the roof by the adjacent second story. Monitoring will be continued at least through spring 2016 (another winter and spring).« less

  15. Green roof stormwater retention: effects of roof surface, slope, and media depth.

    PubMed

    VanWoert, Nicholaus D; Rowe, D Bradley; Andresen, Jeffrey A; Rugh, Clayton L; Fernandez, R Thomas; Xiao, Lan

    2005-01-01

    Urban areas generate considerably more stormwater runoff than natural areas of the same size due to a greater percentage of impervious surfaces that impede water infiltration. Roof surfaces account for a large portion of this impervious cover. Establishing vegetation on rooftops, known as green roofs, is one method of recovering lost green space that can aid in mitigating stormwater runoff. Two studies were performed using several roof platforms to quantify the effects of various treatments on stormwater retention. The first study used three different roof surface treatments to quantify differences in stormwater retention of a standard commercial roof with gravel ballast, an extensive green roof system without vegetation, and a typical extensive green roof with vegetation. Overall, mean percent rainfall retention ranged from 48.7% (gravel) to 82.8% (vegetated). The second study tested the influence of roof slope (2 and 6.5%) and green roof media depth (2.5, 4.0, and 6.0 cm) on stormwater retention. For all combined rain events, platforms at 2% slope with a 4-cm media depth had the greatest mean retention, 87%, although the difference from the other treatments was minimal. The combination of reduced slope and deeper media clearly reduced the total quantity of runoff. For both studies, vegetated green roof systems not only reduced the amount of stormwater runoff, they also extended its duration over a period of time beyond the actual rain event.

  16. Summer Roof Maintenance.

    ERIC Educational Resources Information Center

    Liscum, Curtis L.

    1999-01-01

    Presents the items to review in roofing maintenance to prepare for the impact of summer, including checking drainage, roof-field surface and membrane, flashings, sheet metal, and rooftop equipment, such as skylights and penthouses. A list of roofing facts facility managers should know are highlighted. (GR)

  17. 30 CFR 75.205 - Installation of roof support using mining machines with integral roof bolters.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... machines with integral roof bolters. 75.205 Section 75.205 Mineral Resources MINE SAFETY AND HEALTH... Roof Support § 75.205 Installation of roof support using mining machines with integral roof bolters. When roof bolts are installed by a continuous mining machine with intregal roof bolting equipment: (a...

  18. Estimation of incident solar radiation on the roof of the cultural and sports university centre of the Foundation University Los Libertadores

    NASA Astrophysics Data System (ADS)

    Jiménez, S. A.; Carrillo, V. M.; Rátiva, L. C.

    2016-02-01

    This document shows the estimate of the total solar irradiance incident for the set of solar collectors to be located on the roof of cultural and sports university centre (CSUC) of the Foundation University Los Libertadores (FULL) in Bogotá, Colombia, and they will be part of the climate control system of the pool built inside. The calculation was based on experimental data of global solar radiation on the horizontal surface on March, July, October, November and December, through the three most commonly models used to determine the total solar radiation on tilted surfaces: isotropic sky, HDKR and Perez. The results show differences of less than 5% between the values calculated by the three models for December, the month with lower irradiance. For this month, reductions up to 15% and 19% were observed in the estimated irradiance, relative to those obtained on a horizontal surface on a surface under ideal orientation and inclination, respectively.

  19. 40 CFR 65.45 - External floating roof converted into an internal floating roof.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... External floating roof converted into an internal floating roof. The owner or operator who elects to... 40 Protection of Environment 15 2010-07-01 2010-07-01 false External floating roof converted into an internal floating roof. 65.45 Section 65.45 Protection of Environment ENVIRONMENTAL PROTECTION...

  20. Evaluation of Extended Wall OSB Sheathing Connection under Combined Uplift and Shear Loading for 24-inch Heel Trusses

    Treesearch

    Vladimir Kochkin; Andrew DeRenzis; Xiping Wang

    2014-01-01

    This study was designed to evaluate the performance of the extended wall structural panel connection in resisting combined uplift and shear forces at the roof-to-wall interface with a focus on a truss heel height of 24 in. to address the expected increases in the depth of attic insulation used in Climate Zones 5 and higher. Five full-size roof-wall assemblies were...

  1. BIPV: a real-time building performance study for a roof-integrated facility

    NASA Astrophysics Data System (ADS)

    Aaditya, Gayathri; Mani, Monto

    2018-03-01

    Building integrated photovoltaic system (BIPV) is a photovoltaic (PV) integration that generates energy and serves as a building envelope. A building element (e.g. roof and wall) is based on its functional performance, which could include structure, durability, maintenance, weathering, thermal insulation, acoustics, and so on. The present paper discusses the suitability of PV as a building element in terms of thermal performance based on a case study of a 5.25 kWp roof-integrated BIPV system in tropical regions. Performance of PV has been compared with conventional construction materials and various scenarios have been simulated to understand the impact on occupant comfort levels. In the current case study, PV as a roofing material has been shown to cause significant thermal discomfort to the occupants. The study has been based on real-time data monitoring supported by computer-based building simulation model.

  2. Effects of roof and rainwater characteristics on copper concentrations in roof runoff.

    PubMed

    Bielmyer, Gretchen K; Arnold, W Ray; Tomasso, Joseph R; Isely, Jeff J; Klaine, Stephen J

    2012-05-01

    Copper sheeting is a common roofing material used in many parts of the world. However, copper dissolved from roof sheeting represents a source of copper ions to watersheds. Researchers have studied and recently developed a simple and efficient model to predict copper runoff rates. Important input parameters include precipitation amount, rain pH, and roof angle. We hypothesized that the length of a roof also positively correlates with copper concentration (thus, runoff rates) on the basis that runoff concentrations should positively correlate with contact time between acidic rain and the copper sheet. In this study, a novel system was designed to test and model the effects of roof length (length of roof from crown to the drip edge) on runoff copper concentrations relative to rain pH and roof angle. The system consisted of a flat-bottom copper trough mounted on an apparatus that allowed run length and slope to be varied. Water of known chemistry was trickled down the trough at a constant rate and sampled at the bottom. Consistent with other studies, as pH of the synthetic rainwater decreased, runoff copper concentrations increased. At all pH values tested, these results indicated that run length was more important in explaining variability in copper concentrations than was the roof slope. The regression equation with log-transformed data (R(2) = 0.873) accounted for slightly more variability than the equation with untransformed data (R(2) = 0.834). In log-transformed data, roof angle was not significant in predicting copper concentrations.

  3. Built-up outer wall and roofing sections for double walled envelope homes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brodhead, B.

    1980-01-01

    A site built system that uses the inner envelope wall is described. Blocking and vertical nailers are attached to this wall and sheathed with foil faced drywall to create the envelope cavity. An outer layer of 3 1/2 in. of Expended Poly Styrene provides continuous solid insulation. The trusses are also sheathed in foil faced drywall and insulated with 5 1/2 in. of E.P.S. This effectively surrounds the building with a continuous vapor and infiltration barrier. Construction details as well as cost breakdowns are presented.

  4. 34. Roof vent detail from roof of Bwing, looking west ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    34. Roof vent detail from roof of B-wing, looking west - Offutt Air Force Base, Strategic Air Command Headquarters & Command Center, Headquarters Building, 901 SAC Boulevard, Bellevue, Sarpy County, NE

  5. Green Roofs for Stormwater Management

    EPA Science Inventory

    This project evaluated green roofs as a stormwater management tool. Results indicate that the green roofs are capable of removing 40% of the annual rainfall volume from a roof through retention and evapotranspiration. Rainfall not retained by green roofs is detained, effectively...

  6. Selecting a Roof Membrane.

    ERIC Educational Resources Information Center

    Waldron, Larry W.

    1990-01-01

    Offers a brief synopsis of the unique characteristics of the following roof membranes: (1) built-up roofing; (2) elastoplastic membranes; (3) modified bitumen membranes; (4) liquid applied membranes; and (5) metal roofing. A chart compares the characteristics of the raw membranes only. (MLF)

  7. Roof System EPDM Shrinkage.

    ERIC Educational Resources Information Center

    Betker, Edward

    1998-01-01

    Looks at Ethylene Propylene Diene Terpolymer rubber roof membranes and the potential problems associated with this material's shrinkage. Discusses how long such a roof should perform and issues affecting repair or replacement. Recommends that a building's function be considered in any roofing decision. (RJM)

  8. Mesothelioma Applied Research Foundation

    MedlinePlus

    ... Percentage Donations Tribute Wall Other Giving/Fundraising Opportunities Bitcoin Donation Form FAQs Action Alert: Help us get ... Percentage Donations Tribute Wall Other Giving/Fundraising Opportunities Bitcoin Donation Form FAQs © 2017 Mesothelioma Applied Research Foundation, ...

  9. Up on the Roof: A Systematic Approach to Roof Maintenance.

    ERIC Educational Resources Information Center

    Burd, William

    1979-01-01

    A systematic roof maintenance program is characterized by carefully prepared long- and short-range plans. An essential feature of a systematic approach to roof maintenance is the stress on preventive measures rather than the patching of leaks. (Author)

  10. High-Tech Roof Management.

    ERIC Educational Resources Information Center

    Benzie, Tim

    1997-01-01

    Describes the use of a computerized roof management system (CRMS) for school districts to foster multiple roof maintenance efficiency and cost effectiveness. Highlights CRMS software manufacturer choices, as well as the types of nondestructive testing equipment tools that can be used to evaluate roof conditions. (GR)

  11. EPA's Green Roof Research

    EPA Science Inventory

    This is a presentation on the basics of green roof technology. The presentation highlights some of the recent ORD research projects on green roofs and provices insight for the end user as to the benefits for green roof technology. It provides links to currently available EPA re...

  12. Prevention of residential roof fires by use of a class "A" fire rated roof system.

    PubMed

    Edlich, Richard F; Winters, Kathryne L; Long, William B; Britt, L D

    2004-01-01

    Because residential roof fires remain a life-threatening danger to residential homeowners in the United States, we describe in detail a national fire prevention program for reducing residential roof fires by use of an Underwriters Laboratories Inc. (UL) and National Fire Protection Association Class A fire rated roof system. This Class A system should comply with the test requirements for fire resistance of roof coverings, as outlined in UL 790 or in ASTM International (ASTM) E-108. Both the Asphalt Roofing Manufacturer's Association (ARMA) and the National Roofing Contractors Association (NRCA) have set up guidelines for selecting a new roof for the homeowner. Class A, fiber-glass-based asphalt roofing shingles represent an overwhelming share of the United States residential roofing market, and, as such, the Class A rated roofing system remains an excellent alternative to wood shingles and shakes. Fortunately, the Class A fire rating is available for certain wood shingle products that incorporate a factory-applied, fire resistant treatment. However, in this circumstance, wood products labeled as Class B shakes or shingles must be installed over spaced or solid sheathing that have been covered either with one layer of 1/4 in. (6.4 mm) thick noncombustible roof board, or with one layer of minimum 72-lb. fiber-glass-based mineral surfaced cap sheet, or with another specialty roofing sheet to obtain the Class A fire rating. Clay, tile, slate, and metal have been assigned Class A fire ratings in the codes (but often without testing). These alternative roofing materials are often considerably more expensive. Proper application, ventilation, and insulation of roofing systems are required to prevent heat and moisture buildup in the attic, which can damage the roofing system, making it more susceptible to water leakage as well as ignition in the event of a fire. The NRCA has devised excellent recommendations for the homeowner to prequalify the contractor. In addition, a

  13. Does Spending Money on Education Help? A Reaction to the Heritage Foundation and the "Wall Street Journal."

    ERIC Educational Resources Information Center

    Wainer, Howard

    In June 1993 the "Wall Street Journal" carried a table of data prepared by the Heritage Foundation that listed the states in order of the average amount they expend on each public school student. The table also contained each state's rank on the average score on the Scholastic Aptitude Test (SAT) and the rank of each state in the average…

  14. Roof structural system, similar in design to peaked roofs of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Roof structural system, similar in design to peaked roofs of rolling mill, yet note abandonment of phoenix columns for compression members. - Phoenix Iron Company, Girder Shop No. 6, North of French Creek, west of Gay Street, Phoenixville, Chester County, PA

  15. 29. Attic interior showing roof truss system over waiting room; ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    29. Attic interior showing roof truss system over waiting room; note knob-and-tube wiring system; brick section at far left is rear of tower, which of brick masonry construction above the first story level, joined to the exterior walls of stone masonry; view to southeast along axis of building, 90mm lens and electronic flash illumination. - Southern Pacific Depot, 559 El Camino Real, San Carlos, San Mateo County, CA

  16. Green roofs: potential at LANL

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pacheco, Elena M

    2009-01-01

    Green roofs, roof systems that support vegetation, are rapidly becoming one of the most popular sustainable methods to combat urban environmental problems in North America. An extensive list of literature has been published in the past three decades recording the ecological benefits of green roofs; and now those benefits have been measured in enumerated data as a means to analyze the costs and returns of green roof technology. Most recently several studies have made substantial progress quantifying the monetary savings associated with storm water mitigation, the lessoning of the Urban Heat Island, and reduction of building cooling demands due tomore » the implementation of green roof systems. Like any natural vegetation, a green roof is capable of absorbing the precipitation that falls on it. This capability has shown to significantly decrease the amount of storm water runoff produced by buildings as well as slow the rate at which runoff is dispensed. As a result of this reduction in volume and velocity, storm drains and sewage systems are relieved of any excess stress they might experience in a storm. For many municipalities and private building owners, any increase in storm water mitigation can result in major tax incentives and revenue that does not have to be spent on extra water treatments. Along with absorption of water, vegetation on green roofs is also capable of transpiration, the process by which moisture is evaporated into the air to cool ambient temperatures. This natural process aims to minimize the Urban Heat Island Effect, a phenomenon brought on by the dark and paved surfaces that increases air temperatures in urban cores. As the sun distributes solar radiation over a city's area, dark surfaces such as bitumen rooftops absorb solar rays and their heat. That heat is later released during the evening hours and the ambient temperatures do not cool as they normally would, creating an island of constant heat. Such excessively high temperatures induce

  17. Photovoltaic Roofs

    NASA Technical Reports Server (NTRS)

    Drummond, R. W., Jr.; Shepard, N. F., Jr.

    1984-01-01

    Solar cells perform two functions: waterproofing roof and generating electricity. Sections through horizontal and slanting joints show overlapping modules sealed by L-section rubber strips and side-by-side modules sealed by P-section strips. Water seeping through seals of slanting joints drains along channels. Rooftop photovoltaic array used watertight south facing roof, replacing shingles, tar, and gravel. Concept reduces cost of residential solar-cell array.

  18. Roof instability characteristics and pre-grouting of the roof caving zone in residual coal mining

    NASA Astrophysics Data System (ADS)

    Zhao, Tong; Liu, Changyou

    2017-12-01

    Abandoned roadways and roof caving zones are commonly found in residual coal, and can destroy the integrity of the coal seam and roof. Resulting from mining-induced stress, continuous collapse and fracture instability in roof caving zones (RCZs) jeopardize the safety and efficiency of residual coal mining. Based on the engineering geology conditions of remining face 3101 in Shenghua Mine, the roof fracture and instability features of the RCZ were analyzed through physical simulation, theoretical analysis, and field measurements. In this case, influenced by the RCZ, the main roof across the RCZ fractured and rotated towards the goaf, greatly increasing the working resistance, and crushing the supports. The sudden instability of the coal pillars weakened its support of the main roof, thus resulting in long-key blocks across the RCZ and hinged roof structures, which significantly decreased the stability of the underlying immediate roof. This study establishes a mechanical model for the interactions between the surrounding rock and the supports in the RCZ, determines the reasonable working resistance, and examines the use of pre-grouting solidification restoration technology (PSRT) to solidify the RCZ and reinforce the coal pillars—thus increasing their bearing capacity. Field measurements revealed no roof flaking, inhomogeneous loading or support crushing, indicating that the PSRT effectively controlled the surrounding rock of the RCZ.

  19. Roofing Source File.

    ERIC Educational Resources Information Center

    American School & University, 1998

    1998-01-01

    Provides guidelines for school administrators to aid in the selection of school-roofing systems, and information required to make specification and purchasing decisions. Low-slope roofing systems are examined, as are multiply systems such as modified bitumen, EPDM, thermoplastic, metal, and foam. (GR)

  20. Green Roofs for Stormwater Runoff Control

    EPA Science Inventory

    This project evaluated green roofs as a stormwater management tool. Specifically, runoff quantity and quality from green and flat asphalt roofs were compared. Evapotranspiration from planted green roofs and evaporation from unplanted media roofs were also compared. The influence...

  1. Thermal Performance of Vegetative Roofing Systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Desjarlais, Andre Omer; Zaltash, Abdolreza; Atchley, Jerald Allen

    2010-01-01

    Vegetative roofing, otherwise known as green or garden roofing, has seen tremendous growth in the last decade in the United States. The numerous benefits that green roofs provide have helped to fuel their resurgence in industrial and urban settings. There are many environmental and economical benefits that can be realized by incorporating a vegetative roof into the design of a building. These include storm-water retention, energy conservation, reduction in the urban heat island effect, increased longevity of the roofing membrane, the ability of plants to create biodiversity and filter air contaminants, and beautification of the surroundings by incorporating green space.more » The vegetative roof research project at Oak Ridge National Laboratory (ORNL) was initiated to quantify the thermal performance of various vegetative roofing systems relative to black and white roofs. Single Ply Roofing Institute (SPRI) continued its long-term commitment to cooperative research with ORNL in this project. Low-slope roof systems for this study were constructed and instrumented for continuous monitoring in the mixed climate of East Tennessee. This report summarizes the results of the annual cooling and heating loads per unit area of three vegetative roofing systems with side-by-side comparison to black and white roofing systems as well as a test section with just the growing media without plants. Results showed vegetative roofs reduced heat gain (reduced cooling loads) compared to the white control system due to the thermal mass, extra insulation, and evapo-transpiration associated with the vegetative roofing systems. The 4-inch and tray systems reduced the heat gain by approximately 61%, while the reduction with the 8-inch vegetative roof was found to be approximately 67%. The vegetative roofing systems were more effective in reducing heat gain than in reducing heat losses (heating loads). The reduction in heat losses for the 4-inch and tray systems were found to be

  2. Cleopatra's Bedroom oblique with picture tube wall along walkway. Structure ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Cleopatra's Bedroom oblique with picture tube wall along walkway. Structure is made solely of amber colored bottles. Roof supported by telephone poles. Areas of bottle wall above window opening collapsed in the 1994 Northridge earthquake. Camera facing northeast. - Grandma Prisbrey's Bottle Village, 4595 Cochran Street, Simi Valley, Ventura County, CA

  3. Primary Intraosseous Hemangioma of the Orbital Roof: A Pitfall of Surgery.

    PubMed

    Wu, Chih-Ying; Huang, Hsiang-Ming; Chen, Der-Cherng; Cho, Der-Yang; Wei, Sung-Tai

    2016-09-01

    A primary intraosseous hemangioma (IOH) of the orbital bone is extremely rare. The preferred method of treatment for IOH is total surgical excision with reconstruction. Herein, the authors describe a patient with an orbital roof IOH and the unexpected complications of ptosis and deteriorated exophthalmos. These findings showed that the total surgical excision and subsequent reconstruction provided adequate decompression and prevented further ocular complications from the orbital wall defect.

  4. Office-like Test Chambers to Measure Cool Roof Energy Savings in Four Indian Climates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Arumugam, Rathish; B, Sasank; T, Rajappa

    Selecting a high albedo (solar reflectance) waterproofing layer on the top of a roof helps lower the roof’s surface temperature and reduce the air conditioning energy consumption in the top floor of a building. The annual energy savings depend on factors including weather, internal loads, and building operation schedule. To demonstrate the energy saving potential of high albedo roofs, an apparatus consisting of two nearly identical test chambers (A and B) has been built in four Indian climates: Chennai (hot & humid), Bangalore (temperate), Jhagadia (Hot & dry) and Delhi (composite). Each chamber has well-insulated walls to mimic the coremore » of an office building. Both chambers have the same construction, equipment, and operating schedule, differing only in roof surface. The reinforced cement concrete roof of Chamber A is surfaced with a low-albedo cement layer, while that of Chamber B is surfaced with a high-albedo water proof membrane (change in solar reflectance of 0.28). The experiment will be carried out for one year to explore seasonal variations in energy savings. Initial results in the month of July (post summer) shows that savings from high albedo roof ranges from 0.04 kWh/m2/day in temperate climates, to 0.08 kWh/m2/day in hot & dry climate.« less

  5. Investigation of the microbial communities colonizing prepainted steel used for roofing and walling.

    PubMed

    Huynh, Tran T; Jamil, Ili; Pianegonda, Nicole A; Blanksby, Stephen J; Barker, Philip J; Manefield, Mike; Rice, Scott A

    2017-04-01

    Microbial colonization of prepainted steel, commonly used in roofing applications, impacts their aesthetics, durability, and functionality. Understanding the relevant organisms and the mechanisms by which colonization occurs would provide valuable information that can be subsequently used to design fouling prevention strategies. Here, next-generation sequencing and microbial community finger printing (T-RFLP) were used to study the community composition of microbes colonizing prepainted steel roofing materials at Burrawang, Australia and Kapar, Malaysia over a 52-week period. Community diversity was low and was dominated by Bacillus spp., cyanobacteria, actinobacteria, Cladosporium sp., Epicoccum nigrum, and Teratosphaeriaceae sp. Cultivation-based methods isolated approximately 20 different fungi and bacteria, some of which, such as E. nigrum and Cladosporium sp., were represented in the community sequence data. Fluorescence in situ hybridization imaging showed that fungi were the most dominant organisms present. Analysis of the sequence and T-RFLP data indicated that the microbial communities differed significantly between locations and changed significantly over time. The study demonstrates the utility of molecular ecology tools to identify and characterize microbial communities associated with the fouling of painted steel surfaces and ultimately can enable the targeted development of control strategies based on the dominant species responsible for fouling. © 2016 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

  6. 29 CFR 570.67 - Occupations in roofing operations and on or about a roof (Order 16).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., including painting and coating of existing roofs; the construction of the sheathing or base of roofs (wood..., and shingles of asbestos, asphalt, wood or other materials) to roofs of buildings or other structures...

  7. Lightweight, self-ballasting photovoltaic roofing assembly

    DOEpatents

    Dinwoodie, T.L.

    1998-05-05

    A photovoltaic roofing assembly comprises a roofing membrane (102), a plurality of photovoltaic modules (104, 106, 108) disposed as a layer on top of the roofing membrane (102), and a plurality of pre-formed spacers, pedestals or supports (112, 114, 116, 118, 120, 122) which are respectively disposed below the plurality of photovoltaic modules (104, 106, 108) and integral therewith, or fixed thereto. Spacers (112, 114, 116, 118, 120, 122) are disposed on top of roofing membrane (102). Membrane (102) is supported on conventional roof framing, and attached thereto by conventional methods. In an alternative embodiment, the roofing assembly may have insulation block (322) below the spacers (314, 314', 315, 315'). The geometry of the preformed spacers (112, 114, 116, 118, 120, 122, 314, 314', 315, 315') is such that wind tunnel testing has shown its maximum effectiveness in reducing net forces of wind uplift on the overall assembly. Such construction results in a simple, lightweight, self-ballasting, readily assembled roofing assembly which resists the forces of wind uplift using no roofing penetrations.

  8. Lightweight, self-ballasting photovoltaic roofing assembly

    DOEpatents

    Dinwoodie, Thomas L.

    1998-01-01

    A photovoltaic roofing assembly comprises a roofing membrane (102), a plurality of photovoltaic modules (104, 106, 108) disposed as a layer on top of the roofing membrane (102), and a plurality of pre-formed spacers, pedestals or supports (112, 114, 116, 118, 120, 122) which are respectively disposed below the plurality of photovoltaic modules (104, 106, 108) and integral therewith, or fixed thereto. Spacers (112, 114, 116, 118, 120, 122) are disposed on top of roofing membrane (102). Membrane (102) is supported on conventional roof framing, and attached thereto by conventional methods. In an alternative embodiment, the roofing assembly may have insulation block (322) below the spacers (314, 314', 315, 315'). The geometry of the preformed spacers (112, 114, 116, 118, 120, 122, 314, 314', 315, 315') is such that wind tunnel testing has shown its maximum effectiveness in reducing net forces of wind uplift on the overall assembly. Such construction results in a simple, lightweight, self-ballasting, readily assembled roofing assembly which resists the forces of wind uplift using no roofing penetrations.

  9. Lightweight, self-ballasting photovoltaic roofing assembly

    DOEpatents

    Dinwoodie, Thomas L.

    2006-02-28

    A photovoltaic roofing assembly comprises a roofing membrane (102), a plurality of photovoltaic modules (104, 106, 108) disposed as a layer on top of the roofing membrane (102), and a plurality of pre-formed spacers, pedestals or supports (112, 114, 116, 118, 120, 122) which are respectively disposed below the plurality of photovoltaic modules (104, 106, 108) and integral therewith, or fixed thereto. Spacers (112, 114, 116, 118, 120, 122) are disposed on top of roofing membrane (102). Membrane (102) is supported on conventional roof framing, and attached thereto by conventional methods. In an alternative embodiment, the roofing assembly may have insulation block (322) below the spacers (314, 314', 315, 315'). The geometry of the pre-formed spacers (112, 114, 116, 118, 120, 122, 314, 314', 315, 315') is such that wind tunnel testing has shown its maximum effectiveness in reducing net forces of wind uplift on the overall assembly. Such construction results in a simple, lightweight, self-ballasting, readily assembled roofing assembly which resists the forces of wind uplift using no roofing penetrations.

  10. Mine roof driller-bolter apparatus and method

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hibbard, G.A.; Lumbra, R.C.; Morrison, W.D.

    1983-12-13

    An apparatus for bolting the roof of an underground mine is disclosed comprising a mobile frame, a boom extending from the frame and a housing provided at the end of the frame. The housing supports an upwardly extending stinger, a drilling mechanism including a drill centralizer having a central bore therethrough and a passageway in communication with the central bore, a device for delivering a container of roof bolting anchoring media through the passageway and through the drill centralizer and into a drilled hole, a device for indexing a roof bolt into alignment with the drilled hole and a spinnermore » for driving the roof bolt into the drilled hole. The present invention also provides a method for bolting the roof of an underground mine comprising the steps of stinging a housing against the roof of the mine, moving a drill centralizer into communication with the roof and drilling a hole in the roof. Without retracting the drill centralizer from communication with the roof, a container of roof bolt anchoring media is delivered through the centralizer and into the drilled hole. The drill centralizer is thereafter retracted and the housing is moved to align a roof bolt with a drilled hole. Then the roof bolt is driven into the drilled hole and the bolt anchoring media sets around the bolt.« less

  11. Study of Falling Roof Vibrations in a Production Face at Roof Support Resistance in the Form of Concentrated Force

    NASA Astrophysics Data System (ADS)

    Buyalich, G. D.; Buyalich, K. G.; Umrikhina, V. Yu

    2016-08-01

    One of the main reasons of roof support failures in production faces is mismatch of their parameters and parameters of dynamic impact on the metal structure from the falling roof during its secondary convergences. To assess the parameters of vibrational interaction of roof support with the roof, it was suggested to use computational models of forces application and a partial differential equation of fourth order describing this process, its numerical solution allowed to assess frequency, amplitude and speed of roof strata movement depending on physical and mechanical properties of the roof strata as well as on load bearing and geometry parameters of the roof support. To simplify solving of the differential equation, roof support response was taken as the concentrated force.

  12. Why Cool Roofs?

    ScienceCinema

    Chu, Steven

    2017-12-27

    By installing a cool roof at DOE, the federal government and Secretary Chu are helping to educate families and businesses about the important energy and cost savings that can come with this simple, low-cost technology. Cool roofs have the potential to quickly and dramatically reduce global carbon emissions while saving money every month on consumers' electrical bills.

  13. Technology Solutions Case Study: Innovative Retrofit Foundation Insulation Strategies, Minneapolis, Minnesota

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    Basements in climates 6 & 7 can account for a fraction of a home's total heat loss when fully conditioned. These foundations are a source of moisture, with convection in open block cavities redistributing water from the wall base, usually when heating. Even when block cavities are capped, the cold foundation concrete can act as a moisture source for wood rim joist components that are in contact with the wall. As below-grade basements are increasingly retrofitted for habitable space, cold foundation walls pose increased challenges for moisture durability, energy use, and occupant comfort. To address this challenge, the NorthernSTAR Buildingmore » America Partnership evaluated a retrofit insulation strategy for foundations that is designed for use with open-core concrete block foundation walls. The three main goals were to improve moisture control, improve occupant comfort, and reduce heat loss.« less

  14. INTERIOR VIEW, WEST WALL OF NORTHWEST ATTIC CHAMBER. THIS SPACIOUS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW, WEST WALL OF NORTHWEST ATTIC CHAMBER. THIS SPACIOUS ROOM INCLUDED A ROOF MONITOR FOR LIGHT AND VENTILATION AND A FIREPLACE FOR HEAT. THE WALL OPENING AND DOOR ON EITHER SIDE OF THE FIREPLACE GIVE ONTO A LARGE UNFINISHED SPACE LOCATED OVER THE HOUSE’S WEST WING - The Woodlands, 4000 Woodlands Avenue, Philadelphia, Philadelphia County, PA

  15. 29 CFR 570.67 - Occupations in roofing operations and on or about a roof (Order 16).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... proximity to a roof, including carpentry and metal work, alterations, additions, maintenance and repair... or metal), including roof trusses or joists; gutter and downspout work; the installation and... work performed in connection with the installation of roofs, including related metal work such as...

  16. Roofing research: a bibliography

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Robinson, J.N.; Nichols, C.L.

    1981-04-01

    A listing, indexed by subject, primary author, and secondary authors, is presented of some 530 references in the literature related to roofing research - materials, construction, and in-service problems. Structural design of roofing systems is not covered.

  17. Measuring mine roof bolt strains

    DOEpatents

    Steblay, Bernard J.

    1986-01-01

    A mine roof bolt and a method of measuring the strain in mine roof bolts of this type are disclosed. According to the method, a flat portion on the head of the mine roof bolt is first machined. Next, a hole is drilled radially through the bolt at a predetermined distance from the bolt head. After installation of the mine roof bolt and loading, the strain of the mine roof bolt is measured by generating an ultrasonic pulse at the flat portion. The time of travel of the ultrasonic pulse reflected from the hole is measured. This time of travel is a function of the distance from the flat portion to the hole and increases as the bolt is loaded. Consequently, the time measurement is correlated to the strain in the bolt. Compensation for various factors affecting the travel time are also provided.

  18. 45 CFR 98.2 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... decree, the grandchild, great grandchild, sibling (if such provider lives in separate residence), niece...) structural changes to the foundation, roof, floor, exterior or load-bearing walls of a facility, or the...

  19. 45 CFR 98.2 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... decree, the grandchild, great grandchild, sibling (if such provider lives in separate residence), niece...) structural changes to the foundation, roof, floor, exterior or load-bearing walls of a facility, or the...

  20. 45 CFR 98.2 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... decree, the grandchild, great grandchild, sibling (if such provider lives in separate residence), niece...) structural changes to the foundation, roof, floor, exterior or load-bearing walls of a facility, or the...

  1. 45 CFR 98.2 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... decree, the grandchild, great grandchild, sibling (if such provider lives in separate residence), niece...) structural changes to the foundation, roof, floor, exterior or load-bearing walls of a facility, or the...

  2. 45 CFR 98.2 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... decree, the grandchild, great grandchild, sibling (if such provider lives in separate residence), niece...) structural changes to the foundation, roof, floor, exterior or load-bearing walls of a facility, or the...

  3. Green Roofs for Stormwater Runoff Control - Abstract

    EPA Science Inventory

    This project evaluated green roofs as a stormwater management tool. Specifically, runoff quantity and quality from green and flat asphalt roofs were compared. Evapotranspiration from planted green roofs and evaporation from unplanted media roofs were also compared. The influence...

  4. LIGHTWEIGHT GREEN ROOF SYSTEMS

    EPA Science Inventory

    Applying a Lightweight Green Roof System to a building can achieve in managing storm water runoff, decreasing heat gain, yielding energy savings, and mitigating the heat island effect. Currently, Most green roof systems are considerably heavy and require structural reinforceme...

  5. Field experiment and numerical simulation of coupling non-Darcy flow caused by curtain and pumping well in foundation pit dewatering

    NASA Astrophysics Data System (ADS)

    Wang, Jianxiu; Liu, Xiaotian; Wu, Yuanbin; Liu, Shaoli; Wu, Lingao; Lou, Rongxiang; Lu, Jiansheng; Yin, Yao

    2017-06-01

    High-velocity non-Darcy flow produced larger drawdown than Darcy flow under the same pumping rate. When the non-Darcy flow caused by curtain met non-Darcy flow caused by pumping wells, superposition and amplification effect occurred in the coupling area, the non-Darcy flow was defined as coupling non-Darcy flow. The coupling non-Darcy flow can be produced and controlled using different combination of curtain and pumping wells in foundation pit dewatering to obtain the maximum drawdown using the minimum pumping rate. The Qianjiang Century City Station foundation pit of Hangzhou subway, China, was selected as background. Field experiments were performed to observe the coupling non-Darcy flow in round gravel. A generalized conceptual model was established to study the coupling effect under different combination of curtain and pumping wells. Numerical simulations of the coupling non-Darcy flow in foundation pit dewatering were carried out based on the Forchheimer equation. The non-Darcy flow area and flow velocity were influenced by the coupling effect. Short filter tube, large pumping rate, small horizontal distance between filter tube and diaphragm wall, and small vertical distance between the filter tube and confined aquifer roof effectively strengthened the coupling effect and obtained a large drawdown. The pumping wells installed close to a curtain was an intentional choice designed to create coupling non-Darcy flow and obtain the maximize drawdown. It can be used in the dewatering of a long and narrow foundation pit, such as a subway foundation pit.

  6. Guidelines for Inspecting Your Roof Systems.

    ERIC Educational Resources Information Center

    Watkins, Daniel L.

    2003-01-01

    Provides guidelines for inspecting the roof of a facility. Suggests that periodic roof inspections should be performed on a quarterly or semi-annual basis and after severe storms. Proactively identifying potential problem areas is the best defense against roof leaks. (SLD)

  7. Roofing as a source of nonpoint water pollution.

    PubMed

    Chang, Mingteh; McBroom, Matthew W; Scott Beasley, R

    2004-12-01

    Sixteen wooden structures with two roofs each were installed to study runoff quality for four commonly used roofing materials (wood shingle, composition shingle, painted aluminum, and galvanized iron) at Nacogdoches, Texas. Each roof, either facing NW or SE, was 1.22 m wide x 3.66 m long with a 25.8% roof slope. Thus, there were 32 alternatively arranged roofs, consisting of four roof types x two aspects x four replicates, in the study. Runoff from the roofs was collected through galvanized gutters, downspouts, and splitters. The roof runoff was compared to rainwater collected by a wet/dry acid rain collector for the concentrations of eight water quality variables, i.e. Cu(2+), Mn(2+), Pb(2+), Zn(2+), Mg(2+), Al(3+), EC and pH. Based on 31 storms collected between October 1997 and December 1998, the results showed: (1) concentrations of pH, Cu, and Zn in rainwater already exceed the EPA freshwater quality standards even without pollutant inputs from roofs, (2) Zn and Cu, the two most serious pollutants in roof runoff, exceeded the EPA national freshwater water quality standards in virtually 100% and more than 60% of the samples, respectively, (3) pH, EC, and Zn were the only three variables significantly affected by roofing materials, (4) differences in Zn concentrations were significant among all roof types and between all roof runoff and rainwater samples, (5) although there were no differences in Cu concentrations among all roof types and between roof runoff and rainwater, all means and medians of runoff and rainwater exceeded the national water quality standards, (6) water quality from wood shingles was the worst among the roof types studied, and (7) although SE is the most frequent and NW the least frequent direction for incoming storms, only EC, Mg, Mn, and Zn in wood shingle runoff from the SE were significantly higher than those from the NW; the two aspects affected no other elements in runoff from the other three roof types. Also, Zn concentrations from

  8. Solar collector cell and roof flashing assembly and method of constructing a roof with such an assembly

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mayerovitch, M.D.

    1980-03-25

    A solar collector cell formed as an integral portion of a roof flashing is disclosed as comprising a flashing base having a dihedral surface including a larger base portion and a smaller ramp portion, and a solar collector cell container built integrally with the base portion of the flashing. The combination is designed to be installed in the roof of a dwelling or other building structure. The container portion of the flashing is substantially shorter in height above the roof line than conventional solar collector cell structures added to a roof subsequent to its construction. As a result, the inventionmore » gives the building constructor or owner, the option of either including the solar cell components at the time of construction of the roof to provide a solar heating device, or to fill the solar collector cell container with a temporary support structure, such as roof shakes or tiles. The shape of the solar collector cell and flashing assembly permits the solar collector cell structure to be camouflaged by overlying shakes or tiles of which the roof is constructed.« less

  9. Advanced Energy Efficient Roof System

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jane Davidson

    2008-09-30

    Energy consumption in buildings represents 40 percent of primary U.S. energy consumption, split almost equally between residential (22%) and commercial (18%) buildings.1 Space heating (31%) and cooling (12%) account for approximately 9 quadrillion Btu. Improvements in the building envelope can have a significant impact on reducing energy consumption. Thermal losses (or gains) from the roof make up 14 percent of the building component energy load. Infiltration through the building envelope, including the roof, accounts for an additional 28 percent of the heating loads and 16 percent of the cooling loads. These figures provide a strong incentive to develop and implementmore » more energy efficient roof systems. The roof is perhaps the most challenging component of the building envelope to change for many reasons. The engineered roof truss, which has been around since 1956, is relatively low cost and is the industry standard. The roof has multiple functions. A typical wood frame home lasts a long time. Building codes vary across the country. Customer and trade acceptance of new building products and materials may impede market penetration. The energy savings of a new roof system must be balanced with other requirements such as first and life-cycle costs, durability, appearance, and ease of construction. Conventional residential roof construction utilizes closely spaced roof trusses supporting a layer of sheathing and roofing materials. Gypsum board is typically attached to the lower chord of the trusses forming the finished ceiling for the occupied space. Often in warmer climates, the HVAC system and ducts are placed in the unconditioned and otherwise unusable attic. High temperature differentials and leaky ducts result in thermal losses. Penetrations through the ceilings are notoriously difficult to seal and lead to moisture and air infiltration. These issues all contribute to greater energy use and have led builders to consider construction of a conditioned attic

  10. DOE Office of Scientific and Technical Information (OSTI.GOV)

    none,

    This case study describes a DOE Zero Energy Ready Home in Houston, Texas, that scored HERS 39 without PV and HERS 29 with PV. This 5,947 ft2 custom home has 11.5-inch ICF walls. The attic is insulated along the roof line with 5 to 7 inches of open-cell spray foam. Most of the home's drinking water is supplied by a 11,500-gallon rainwater cistern. Hurricane strapping connects the roof to the walls. The triple-pane windows are impact resistant. The foundation is a raised slab.

  11. Innovative Retrofit Insulation Strategies for Concrete Masonry Foundations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Huelman, P.; Goldberg, L.; Jacobson, R.

    Basements in climates 6 and 7 can account for a fraction of a home's total heat loss when fully conditioned. Such foundations are a source of moisture, with convection in open block cavities redistributing water from the wall base, usually when heating. Even when block cavities are capped, the cold foundation concrete can act as a moisture source for wood rim joist components that are in contact with it. Because below-grade basements are increasingly used for habitable space, cold foundation walls pose challenges for moisture contribution, energy use, and occupant comfort.

  12. GREEN ROOFS — A GROWING TREND

    EPA Science Inventory

    One of the most interesting stormwater control systems under evaluation by EPA are “green roofs”. Green roofs are vegetative covers applied to building roofs to slow, or totally absorb, rainfall runoff during storms. While the concept of over-planted roofs is very ancient, the go...

  13. Leaky Roof? Tight Budget? No Problem!

    ERIC Educational Resources Information Center

    Szcygiel, Tony L.

    1998-01-01

    Examines the piece-by-piece approach to school re-roofing that can help alleviate both maintenance and budget concerns. Addresses the question of whether an entire new roof is required and discusses funding and why a single-ply roof is a good choice for partial replacement. (GR)

  14. 5. EXTERIOR OF FRONT AND SOUTHWEST WALL OF HOUSE SHOWING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. EXTERIOR OF FRONT AND SOUTHWEST WALL OF HOUSE SHOWING GABLE-ROOFED 1965 ADDITION WITH SLIDING-GLASS WINDOWS. VIEW TO NORTH. - Bishop Creek Hydroelectric System, Plant 4, Worker Cottage, Bishop Creek, Bishop, Inyo County, CA

  15. Foundation Design against Frost Action in Europe.

    DTIC Science & Technology

    1988-03-01

    the inside of the foundation wall and consisted of 50mm of ’Rockwool’ (a mineral wool ). This insulation guides heat from the house down toward the...Separation of the floor slab from the inner part of the foundation wall by introducing mineral wool (Fig. 49c) gives a further slight reduction in...construction consisting, for example, of wood and mineral wool and including air spaces. Rt is the thermal resistance of the composite floor from surface to

  16. 30 CFR 75.204 - Roof bolting.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... would not anchor in competent strata, corrective action shall be taken. (3) The installed torque or.... (4) In each roof bolting cycle, the actual torque or tension of the first tensioned roof bolt... drill head used, at least one roof bolt out of every four installed shall be measured for actual torque...

  17. 8. Detail view, greenhouse, south wall (Note the fragments of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Detail view, greenhouse, south wall (Note the fragments of carved frieze and the construction seam running across the upper-right-hand corner of the photograph. The south wall was extended eastward and upward in the nineteenth century in order to accommodate the a new all-encompassing roof for the four adjacent units). - John Bartram House & Garden, Greenhouse, 54th Street & LIndbergh Boulevard, Philadelphia, Philadelphia County, PA

  18. Mobilization and distribution of lead originating from roof dust and wet deposition in a roof runoff system.

    PubMed

    Yu, Jianghua; Yu, Haixia; Huang, Xiaogu

    2015-12-01

    In this research, the mobilization and distribution of lead originating in roof dust and wet deposition were investigated within a roof dust-rooftop-runoff system. The results indicated that lead from roof dust and wet deposition showed different transport dynamics in runoff system and that this process was significantly influenced by the rainfall intensity. Lead present in the roof dust could be easily washed off into the runoff, and nearly 60 % of the total lead content was present in particulate form. Most of the lead from the roof dust was transported during the late period of rainfall; however, the lead concentration was higher for several minutes at the rainfall beginning. Even though some of the lead from wet deposition, simulated with a standard isotope substance, was adsorbed onto adhered roof dust and/or retained on rooftop in runoff system, most of it (50-82 %) remained as dissolved lead in the runoff for rainfall events of varying intensity. Regarding the distribution of lead in the runoff system, the results indicated that it could be carried in the runoff in dissolved and particulate form, be adsorbed to adhered roof dust, or remain on the rooftop because of adsorption to the roof material. Lead from the different sources showed different distribution patterns that were also related to the rainfall intensity. Higher rainfall intensity resulted in a higher proportion of lead in the runoff and a lower proportion of lead remaining on the rooftop.

  19. Establishing Green Roof Infrastructure Through Environmental Policy Instruments

    NASA Astrophysics Data System (ADS)

    Carter, Timothy; Fowler, Laurie

    2008-07-01

    Traditional construction practices provide little opportunity for environmental remediation to occur in urban areas. As concerns for environmental improvement in urban areas become more prevalent, innovative practices which create ecosystem services and ecologically functional land cover in cities will be in higher demand. Green roofs are a prime example of one of these practices. The past decade has seen the North American green roof industry rapidly expand through international green roof conferences, demonstration sites, case studies, and scientific research. This study evaluates existing international and North American green roof policies at the federal, municipal, and community levels. Green roof policies fall into a number of general categories, including direct and indirect regulation, direct and indirect financial incentives, and funding of demonstration or research projects. Advantages and disadvantages of each category are discussed. Salient features and a list of prompting standards common to successfully implemented green roof strategies are then distilled from these existing policies. By combining these features with data collected from an experimental green roof site in Athens, Georgia, the planning and regulatory framework for widespread green roof infrastructure can be developed. The authors propose policy instruments be multi-faceted and spatially focused, and also propose the following recommendations: (1) Identification of green roof overlay zones with specifications for green roofs built in these zones. This spatial analysis is important for prioritizing areas of the jurisdiction where green roofs will most efficiently function; (2) Offer financial incentives in the form of density credits and stormwater utility fee credits to help overcome the barriers to entry of the new technology; (3) Construct demonstration projects and institutionalize a commitment greening roofs on publicly-owned buildings as an effective way of establishing an educated

  20. Establishing green roof infrastructure through environmental policy instruments.

    PubMed

    Carter, Timothy; Fowler, Laurie

    2008-07-01

    Traditional construction practices provide little opportunity for environmental remediation to occur in urban areas. As concerns for environmental improvement in urban areas become more prevalent, innovative practices which create ecosystem services and ecologically functional land cover in cities will be in higher demand. Green roofs are a prime example of one of these practices. The past decade has seen the North American green roof industry rapidly expand through international green roof conferences, demonstration sites, case studies, and scientific research. This study evaluates existing international and North American green roof policies at the federal, municipal, and community levels. Green roof policies fall into a number of general categories, including direct and indirect regulation, direct and indirect financial incentives, and funding of demonstration or research projects. Advantages and disadvantages of each category are discussed. Salient features and a list of prompting standards common to successfully implemented green roof strategies are then distilled from these existing policies. By combining these features with data collected from an experimental green roof site in Athens, Georgia, the planning and regulatory framework for widespread green roof infrastructure can be developed. The authors propose policy instruments be multi-faceted and spatially focused, and also propose the following recommendations: (1) Identification of green roof overlay zones with specifications for green roofs built in these zones. This spatial analysis is important for prioritizing areas of the jurisdiction where green roofs will most efficiently function; (2) Offer financial incentives in the form of density credits and stormwater utility fee credits to help overcome the barriers to entry of the new technology; (3) Construct demonstration projects and institutionalize a commitment greening roofs on publicly-owned buildings as an effective way of establishing an educated

  1. Hydrological performance of an extensive green roof: a case study from the central Europe (Bustehrad, Czech Republic)

    NASA Astrophysics Data System (ADS)

    Tománková, Klára; Sněhota, Michal; Jelínková, Vladimíra

    2016-04-01

    Extensive green roofs with a thin growing medium require minimal maintenance, and in general no irrigation. The proper functioning of such systems rests with their structural constituents, especially with the substrate used for planting. An extensive green roof with poorly developed vegetation and with a soil layer of a maximum thickness of 5 cm mixed with local stripped topsoil with crushed bricks and green waste was studied with respect to the hydrological behavior. The substrate classified as loam comprises a significant proportion of very fine particles and thus it is prone to clogging up of soil pores and forming of fissures on the surface. The green roof studied is well equipped for measuring meteorological data including air temperature, wind speed and direction, net radiation, relative humidity, and rainfall intensity. The meteorological information on the site is completed by soil temperature measurement. The 12 m long transect is equipped with eight time domain reflectometry probes (TDR) to monitor soil water content. Soil physical properties (bulk density, porosity, grain size distribution) and soil hydraulic characteristics (soil water retention curve) were obtained. The numerical modeling of transient soil water movement in the green roof substrate was performed using a two-dimensional model based on the Richards' equation. Results were compared with the soil water content data acquired. Six alternative scenarios were formulated to discuss possible improvement of green roof functioning and four selected scenarios were simulated. The study helped us to improve our understanding of the flow processes through the green roof soil system under study. The alternative scenario simulations allowed hydrological assessment of roof construction amendments. The research was realized as a part of the University Centre for Energy Efficient Buildings supported by the EU and with financial support from the Czech Science Foundation under project number 14-10455P.

  2. Can green roof act as a sink for contaminants? A methodological study to evaluate runoff quality from green roofs.

    PubMed

    Vijayaraghavan, K; Joshi, Umid Man

    2014-11-01

    The present study examines whether green roofs act as a sink or source of contaminants based on various physico-chemical parameters (pH, conductivity and total dissolved solids) and metals (Na, K, Ca, Mg, Al, Fe, Cr, Cu, Ni, Zn, Cd and Pb). The performance of green roof substrate prepared using perlite, vermiculite, sand, crushed brick, and coco-peat, was compared with local garden soil based on improvement of runoff quality. Portulaca grandiflora was used as green roof vegetation. Four different green roof configurations, with vegetated and non-vegetated systems, were examined for several artificial rain events (un-spiked and metal-spiked). In general, the vegetated green roof assemblies generated better-quality runoff with less conductivity and total metal ion concentration compared to un-vegetated assemblies. Of the different green roof configurations examined, P. grandiflora planted on green roof substrate acted as sink for various metals and showed the potential to generate better runoff. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. 609th Iraqi National Guard Battalion Garrison, Thi Qar Governorate, Iraq

    DTIC Science & Technology

    2006-07-25

    views of structural members (reinforced concrete footers, columns , beams , floor, and roof slabs). Mechanical drawings included plumbing plans and...well as reinforced concrete columns and beams . The exterior walls were constructed with sand lime block. Although the assessment team did not...foundation support for the perimeter wall included reinforced concrete footers to support the columns and a reinforced concrete tie beam under the wall

  4. Optimizing the position of insulating materials in flat roofs exposed to sunshine to gain minimum heat into buildings under periodic heat transfer conditions.

    PubMed

    Shaik, Saboor; Talanki, Ashok Babu Puttranga Setty

    2016-05-01

    Building roofs are responsible for the huge heat gain in buildings. In the present work, an analysis of the influence of insulation location inside a flat roof exposed directly to the sun's radiation was performed to reduce heat gain in buildings. The unsteady thermal response parameters of the building roof such as admittance, transmittance, decrement factor, and time lags have been investigated by solving a one-dimensional diffusion equation under convective periodic boundary conditions. Theoretical results of four types of walls were compared with the experimental results available in literature. The results reveal that the roof with insulation placed at the outer side and at the center plane of the roof is the most energy efficient from the lower decrement factor point of view and the roof with insulation placed at the center plane and the inner side of the roof is the best from the highest time lag point of view among the seven studied configurations. The composite roof with expanded polystyrene insulation located at the outer side and at the center plane of the roof is found to be the best roof from the lowest decrement factor (0.130) point of view, and the composite roof with resin-bonded mineral wool insulation located at the center plane and at the inner side of the roof is found to be energy efficient from the highest time lag point (9.33 h) of view among the seven configurations with five different insulation materials studied. The optimum fabric energy storage thicknesses of reinforced cement concrete, expanded polystyrene, foam glass, rock wool, rice husk, resin-bonded mineral wool, and cement plaster were computed. From the results, it is concluded that rock wool has the least optimum fabric energy storage thickness (0.114 m) among the seven studied building roof materials.

  5. Innovative Retrofit Insulation Strategies for Concrete Masonry Foundations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Huelman, P.; Goldberg, L.; Jacobson, R.

    This study was designed to test a new approach for foundation insulation retrofits, with the goal of demonstrating improved moisture control, improved occupant comfort, and reduced heat loss. Because conducting experimental research on existing below-grade assemblies is very difficult, most of the results are based on simulations. The retrofit approach consists of filling open concrete block cores with an insulating material and adding R-10 exterior insulation that extends 1 ft below grade. The core fill is designed to improve the R-value of the foundation wall and increase the interior wall surface temperature, but more importantly to block convection currents thatmore » could otherwise increase moisture loads on the foundation wall and interior space. The exterior insulation significantly reduces heat loss through the most exposed part of the foundation and further increases the interior wall surface temperature. This improves occupant comfort and decreases the risk of condensation. Such an insulation package avoids the full-depth excavation necessary for exterior insulation retrofits, reduces costs, and eliminates the moisture and indoor air quality risks associated with interior insulation retrofits. Retrofit costs for the proposed approach were estimated at roughly half those of a full-depth exterior insulation retrofit.« less

  6. Water quality function of an extensive vegetated roof.

    PubMed

    Todorov, Dimitar; Driscoll, Charles T; Todorova, Svetoslava; Montesdeoca, Mario

    2018-06-01

    In this paper we present the results of a four-year study of water quality in runoff from an extensive, sedum covered, vegetated roof on an urban commercial building. Monitoring commenced seven months after the roof was constructed, with the first growing season. Stormwater drainage quality function of the vegetated roof was compared to a conventional (impermeable, high-albedo) membrane roof in addition to paired measurements of wet and bulk depositions at the study site. We present concentrations and fluxes of nutrients and major solutes. We discuss seasonal and year-to-year variation in water quality of drainage from the vegetated roof and how it compares with atmospheric deposition and drainage from the impermeable roof. Drainage waters from the vegetated roof exhibited a high concentration of nutrients compared to atmospheric deposition, particularly during the warm temperature growing season. However, nutrient losses were generally low because of the strong retention of water by the vegetated roof. There was marked variation in the retention of nutrients by season due to variations in concentrations in drainage from the vegetated roof. The vegetated roof was a sink of nitrogen, total phosphorus and chloride, and a source of phosphate and dissolved inorganic and organic carbon. Chloride exhibited elevated inputs and leaching during the winter. The drainage from the vegetated and impermeable roofs met the United States Environmental Protection Agency freshwater standards for all parameters, except for total phosphorus. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Concrete airship sheds at Orly, France. Part II

    NASA Technical Reports Server (NTRS)

    FREYSSINET

    1925-01-01

    This report deals mainly with the methods of construction employed when after the plan had been approved. The foundation, side walls, doors and roof are all discussed and the economic savings resulting from this method of construction.

  8. The Powder Magazine: Historical Documentation and Architectural Maintenance, Powder Magazine Park, R.E. Bob Woodruff Lake, Montgomery, Alabama

    DTIC Science & Technology

    1999-01-01

    foundation section 13 Figure 11. Photo of rear (west side) of the Powder Magazine, looking east, showing mounded gravel 13 Figure 12. Photo...11. Photo of rear (west side) of the Powder Magazine, looking east, showing mounded gravel. The Powder Magazine, Montgomery, Alabama 13... termite tunnels from ceiling, vent holes filled with red coarse sand, drip marks in debris at north wall base, north side of roof sagging, roof

  9. 29 CFR 570.67 - Occupations in roofing operations and on or about a roof (Order 16).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... pitch, asphalt prepared paper, tile, composite roofing materials, slate, metal, translucent materials, and shingles of asbestos, asphalt, wood or other materials) to roofs of buildings or other structures...

  10. 29 CFR 570.67 - Occupations in roofing operations and on or about a roof (Order 16).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... pitch, asphalt prepared paper, tile, composite roofing materials, slate, metal, translucent materials, and shingles of asbestos, asphalt, wood or other materials) to roofs of buildings or other structures...

  11. 29 CFR 570.67 - Occupations in roofing operations and on or about a roof (Order 16).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... pitch, asphalt prepared paper, tile, composite roofing materials, slate, metal, translucent materials, and shingles of asbestos, asphalt, wood or other materials) to roofs of buildings or other structures...

  12. An environmental cost-benefit analysis of alternative green roofing strategies

    NASA Astrophysics Data System (ADS)

    Richardson, M.; William, R. K.; Goodwell, A. E.; Le, P. V.; Kumar, P.; Stillwell, A. S.

    2016-12-01

    Green roofs and cool roofs are alternative roofing strategies that mitigate urban heat island effects and improve building energy performance. Green roofs consist of soil and vegetation layers that provide runoff reduction, thermal insulation, and potential natural habitat, but can require regular maintenance. Cool roofs involve a reflective layer that reflects more sunlight than traditional roofing materials, but require additional insulation during winter months. This study evaluates several roofing strategies in terms of energy performance, urban heat island mitigation, water consumption, and economic cost. We use MLCan, a multi-layer canopy model, to simulate irrigated and non-irrigated green roof cases with shallow and deep soil depths during the spring and early summer of 2012, a drought period in central Illinois. Due to the dry conditions studied, periodic irrigation is implemented in the model to evaluate its effect on evapotranspiration. We simulate traditional and cool roof scenarios by altering surface albedo and omitting vegetation and soil layers. We find that both green roofs and cool roofs significantly reduce surface temperature compared to the traditional roof simulation. Cool roof temperatures always remain below air temperature and, similar to traditional roofs, require low maintenance. Green roofs remain close to air temperature and also provide thermal insulation, runoff reduction, and carbon uptake, but might require irrigation during dry periods. Due to the longer lifetime of a green roof compared to cool and traditional roofs, we find that green roofs realize the highest long term cost savings under simulated conditions. However, using longer-life traditional roof materials (which have a higher upfront cost) can help decrease this price differential, making cool roofs the most affordable option due to the higher maintenance costs associated with green roofs

  13. How Cool Is Your Roof?

    ERIC Educational Resources Information Center

    Fickes, Michael

    2001-01-01

    Explains a concept called cool roof that is used to reduce electricity costs for air conditioning, and also reduce the price of air conditioning units. Discusses the light reflecting capabilities of metal roofing as well as coatings that can stop leaks. (GR)

  14. Impact of Sustainable Cool Roof Technology on Building Energy Consumption

    NASA Astrophysics Data System (ADS)

    Vuppuluri, Prem Kiran

    Highly reflective roofing systems have been analyzed over several decades to evaluate their ability to meet sustainability goals, including reducing building energy consumption and mitigating the urban heat island. Studies have isolated and evaluated the effects of climate, surface reflectivity, and roof insulation on energy savings, thermal load mitigation and also ameliorating the urban heat island. Other sustainable roofing systems, like green-roofs and solar panels have been similarly evaluated. The motivation for the present study is twofold: the first goal is to present a method for simultaneous evaluation and inter-comparison of multiple roofing systems, and the second goal is to quantitatively evaluate the realized heating and cooling energy savings associated with a white roof system compared to the reduction in roof-top heat flux. To address the first research goal a field experiment was conducted at the International Harvester Building located in Portland, OR. Thermal data was collected for a white roof, vegetated roof, and a solar panel shaded vegetated roof, and the heat flux through these roofing systems was compared against a control patch of conventional dark roof membrane. The second research goal was accomplished using a building energy simulation program to determine the impact of roof area and roof insulation on the savings from a white roof, in both Portland and Phoenix. The ratio of cooling energy savings to roof heat flux reduction from replacing a dark roof with a white roof was 1:4 for the month of July, and 1:5 annually in Portland. The COP of the associated chillers ranges from 2.8-4.2, indicating that the ratio of cooling energy savings to heat flux reduction is not accounted for solely by the COP of the chillers. The results of the building simulation indicate that based on energy savings alone, white roofs are not an optimal choice for Portland. The benefits associated with cooling energy savings relative to a black roof are offset by

  15. TASK 2.5.7 FIELD EXPERIMENTS TO EVALUATE COOL-COLORED ROOFING

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Miller, William A; Cherry, Nigel J; Allen, Richard Lowell

    Aesthetically pleasing dark roofs can be formulated to reflect like a highly reflective white roof in the near infrared portion of the solar spectrum. New paint pigments increase the near infrared reflectance of exterior finishes by minimizing the absorption of near-infrared radiation (NIR). The boost in the NIR reflectance drops the surface temperatures of roofs and walls, which in turn reduces cooling-energy use and provides savings for the homeowner and relief for the utilities. In moderate and hot climates, a roof surface with high solar reflectance and high thermal emittance was shown by Akbari et al. (2004) and by Parkermore » and Sherwin (1998) to reduce the exterior temperature and produce savings in comfort cooling. The new cool color pigments can potentially reduce emissions of carbon dioxide, which in turn reduces metropolitan heat buildup and urban smog. The pigments can also help conserve water resources otherwise used to clean and process fuel consumed by fossil-fuel driven power plants. Cool roofs also result in a lower ambient temperature that further decreases the need for air conditioning, retards smog formation, and improves thermal comfort. Parker, Sonne and Sherwin (2002) demonstrated that white barrel and white flat tiles reduced cooling energy consumption by 22% of the base load used by an adjacent and identical home having direct nailed dark shingles. Part of the savings was due to the reflectance of the white tiles; however, another part was due to the mass of the tile and to the venting occurring within the double batten installation. With, Cherry and Haig (2009) have studied the influence of the thermal mass and batten space ventilation and have found that, referenced to an asphalt shingle system, it can be equivalent to an additional 28 points of solar reflectivity. The double batten arrangement has wooden counter battens laid vertically (soffit-to-ridge) against the roof deck, and then the conventional battens are laid horizontally

  16. Performance evaluation on cool roofs for green remodeling

    NASA Astrophysics Data System (ADS)

    Yun, Yosun; Cho, Dongwoo; Cho, Kyungjoo

    2018-06-01

    Cool roofs refer that maximize heat emission, and minimize the absorption of solar radiation energy, by applying high solar reflectance paints, or materials to roofs or rooftops. The application of cool roofs to existing buildings does not need to take structural issues into consideration, as rooftop greening, is an alternative that can be applied to existing buildings easily. This study installed a cool roofs on existing buildings, and evaluated the performances, using the results to propose certification standards for green remodeling, considering the cool roof-related standards.

  17. Green Roofs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    A New Technology Demonstration Publication Green roofs can improve the energy performance of federal buildings, help manage stormwater, reduce airborne emissions, and mitigate the effects of urban heat islands.

  18. 40 CFR 63.1063 - Floating roof requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... the point of refloating the floating roof shall be continuous and shall be performed as soon as... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Floating roof requirements. 63.1063...) National Emission Standards for Storage Vessels (Tanks)-Control Level 2 § 63.1063 Floating roof...

  19. Roof Moisture Surveys: Current State Of The Technology

    NASA Astrophysics Data System (ADS)

    Tobiasson, Wayne

    1983-03-01

    Moisture is the big enemy of compact roofing systems. Non-destructive nuclear, capacitance and infrared methods can all find wet insulation in such roofs but a few core samples are needed for verification. Nuclear and capacitance surveys generate quantitative results at grid points but examine only a small portion of the roof. Quantitative results are not usually provided by infrared scanners but they can rapidly examine every square inch of the roof. Being able to find wet areas when they are small is an important advantage. Prices vary with the scope of the investigation. For a particular scope, the three techniques are often cost-competitive. The limitations of each technique are related to the people involved as well as the equipment. When the right people are involved, non-destructive surveys are a very effective method for improving the long-term performance and reducing the life-cycle costs of roofing systems. Plans for the maintenance, repair or replacement of a roof should include a roof moisture survey.

  20. Daylighting performance and thermal implications of skylights vs. south-facing roof monitors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rosenbaum, M.; Coldham, B.

    1997-12-31

    This paper reports the results of a comparison of skylights vs. south-facing roof monitors for daylighting the north wall zone of a 10,000 ft{sup 2} office building near Manchester, NH. A physical model was constructed and tested. Simultaneously, the building`s annual thermal performance was modeled with Energy-10 hourly simulation software, and its peak heating and cooling load performance was modeled with the Carrier Corp. Hourly Analysis Program (HAP). Apertures were built into the roof of the model, and several skylight and south-facing roof monitor configurations were tested in both clear and overcast conditions. A design goal was to have themore » building be daylit on overcast as well as clear days. This goal was based more on enhancement of the working environment than it was on electrical energy savings. Monitors with overhangs performed poorly in the overcast conditions--it was determined that 2.4 times as much monitor aperture was needed to yield equivalent light levels in overcast conditions. The thermal models showed that the annual heating and cooling energy cost for the building was the same for either strategy, but that peak cooling loads and peak heating loads were lower with the skylit version. The authors concluded that skylights were preferred over monitors in this application, due to similar annual energy costs, lower peak loads, and lower construction cost.« less

  1. Thin soil layer of green roof systems studied by X-Ray CT

    NASA Astrophysics Data System (ADS)

    Šácha, Jan; Jelínková, Vladimíra; Dohnal, Michal

    2016-04-01

    The popular non-invasive visualization technique of X-ray computed tomography (CT) has been used for 3D examination of thin soil layer of vegetated roof systems. The two categories of anthropogenic soils, usually used for green roof systems, were scanned during the first months after green roof system construction. First was represented by stripped topsoil with admixed crushed bricks and was well graded in terms of particle size distribution. The other category represented a commercial lightweight technogenic substrate. The undisturbed soil samples of total volume of 62.8 ccm were studied be means of X-ray Computed Tomography using X-ray Inspection System GE Phoenix Nanomex 180T with resulting spatial resolution about 57 μm in all directions. For both soil categories visible macroporosity, connectivity (described by the Euler characteristic), dimensionless connectivity and critical cross section of pore network were determined. Moreover, the temporal structural changes of studied soils were discussed together with heat and water regime of the green roof system. The analysis of CT images of anthropogenic soils was problematic due to the different X-ray attenuation of individual constituents. The correct determination of the threshold image intensity differentiating the soil constituents from the air phase had substantial importance for soil pore network analyses. However, X-ray CT derived macroporosity profiles reveal significant temporal changes notably in the soil comprised the stripped topsoil with admixed crushed bricks. The results implies that the technogenic substrate is structurally more stable over time compared to the stripped topsoil. The research was realized as a part of the University Centre for Energy Efficient Buildings supported by the EU and with financial support from the Czech Science Foundation under project number 14-10455P.

  2. Protected Membrane Roofs: A Sustainable Roofing Solution.

    ERIC Educational Resources Information Center

    Roodvoets, David L.

    2003-01-01

    Examines the benefits of protected membrane roofing (PMR) for school buildings. PMR uses an upside-down approach, where the insulation is placed on top of the waterproofing membrane to improve membrane effectiveness, reduce ultraviolet degradation, and improve insulation efficiency. The article explains what makes PMR sustainable, focusing on…

  3. Construction of Experimental Roofing.

    DTIC Science & Technology

    1981-11-01

    buildings at Fort Benning, GA; Fort Knox, KY; and Fort Lewis, WA. Sheets of EPDM synthetic rubber were installed on buildings at Forts Benning and Lewis...Contract and Unit Costs 14 5 Polyurethane Foam Roofing -- Initial Physical Properties 28 6 EPDM Sheet Rubber Roofing -- Initial Physical Properties 30 7...the new system. The system selected for Area A was an EPDM synthetic rubber manufactured by Carlisle Tire and Rubber Company. The contract specified

  4. Green roof valuation: a probabilistic economic analysis of environmental benefits.

    PubMed

    Clark, Corrie; Adriaens, Peter; Talbot, F Brian

    2008-03-15

    Green (vegetated) roofs have gained global acceptance as a technologythat has the potential to help mitigate the multifaceted, complex environmental problems of urban centers. While policies that encourage green roofs exist atthe local and regional level, installation costs remain at a premium and deter investment in this technology. The objective of this paper is to quantitatively integrate the range of stormwater, energy, and air pollution benefits of green roofs into an economic model that captures the building-specific scale. Currently, green roofs are primarily valued on increased roof longevity, reduced stormwater runoff, and decreased building energy consumption. Proper valuation of these benefits can reduce the present value of a green roof if investors look beyond the upfront capital costs. Net present value (NPV) analysis comparing a conventional roof system to an extensive green roof system demonstrates that at the end of the green roof lifetime the NPV for the green roof is between 20.3 and 25.2% less than the NPV for the conventional roof over 40 years. The additional upfront investment is recovered at the time when a conventional roof would be replaced. Increasing evidence suggests that green roofs may play a significant role in urban air quality improvement For example, uptake of N0x is estimated to range from $1683 to $6383 per metric ton of NOx reduction. These benefits were included in this study, and results translate to an annual benefit of $895-3392 for a 2000 square meter vegetated roof. Improved air quality leads to a mean NPV for the green roof that is 24.5-40.2% less than the mean conventional roof NPV. Through innovative policies, the inclusion of air pollution mitigation and the reduction of municipal stormwater infrastructure costs in economic valuation of environmental benefits of green roofs can reduce the cost gap that currently hinders U.S. investment in green roof technology.

  5. Green roof hydrologic performance and modeling: a review.

    PubMed

    Li, Yanling; Babcock, Roger W

    2014-01-01

    Green roofs reduce runoff from impervious surfaces in urban development. This paper reviews the technical literature on green roof hydrology. Laboratory experiments and field measurements have shown that green roofs can reduce stormwater runoff volume by 30 to 86%, reduce peak flow rate by 22 to 93% and delay the peak flow by 0 to 30 min and thereby decrease pollution, flooding and erosion during precipitation events. However, the effectiveness can vary substantially due to design characteristics making performance predictions difficult. Evaluation of the most recently published study findings indicates that the major factors affecting green roof hydrology are precipitation volume, precipitation dynamics, antecedent conditions, growth medium, plant species, and roof slope. This paper also evaluates the computer models commonly used to simulate hydrologic processes for green roofs, including stormwater management model, soil water atmosphere and plant, SWMS-2D, HYDRUS, and other models that are shown to be effective for predicting precipitation response and economic benefits. The review findings indicate that green roofs are effective for reduction of runoff volume and peak flow, and delay of peak flow, however, no tool or model is available to predict expected performance for any given anticipated system based on design parameters that directly affect green roof hydrology.

  6. Metal and nutrient dynamics on an aged intensive green roof.

    PubMed

    Speak, A F; Rothwell, J J; Lindley, S J; Smith, C L

    2014-01-01

    Runoff and rainfall quality was compared between an aged intensive green roof and an adjacent conventional roof surface. Nutrient concentrations in the runoff were generally below Environmental Quality Standard (EQS) values and the green roof exhibited NO3(-) retention. Cu, Pb and Zn concentrations were in excess of EQS values for the protection of surface water. Green roof runoff was also significantly higher in Fe and Pb than on the bare roof and in rainfall. Input-output fluxes revealed the green roof to be a potential source of Pb. High concentrations of Pb within the green roof soil and bare roof dusts provide a potential source of Pb in runoff. The origin of the Pb is likely from historic urban atmospheric deposition. Aged green roofs may therefore act as a source of legacy metal pollution. This needs to be considered when constructing green roofs with the aim of improving pollution remediation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Use of treated woods in roof assembly.

    PubMed

    Edlich, Richard F; Winters, Kathryne L; Long, William B; Gubler, K Dean; Britt, L D

    2005-01-01

    On February 12, 2002, the US Environmental Protection Agency (EPA) announced a voluntary decision by industry to move consumer use of treated lumber products away from a variety of pressure-treated wood that contains Arsenate (As) by December 31, 2003, in favor of new alternative wood preservatives. It is the purpose of this report to outline legislative efforts to ban the use of chromated copper arsenate (CCA)-treated wood for residential roofing in the State of Oregon. At the time that the legislation was introduced, it was coincidental that the National Roofing Contractors Association (NRCA) recommended that CCA-treated wood should not be used in residential roofing. A summary of the report is included in this review. Finally, we discuss some of the potentially harmful environmental hazards of wood preservatives on the environment. In addition to the toxicity of pressure-treated wood on our environment, we point out that wood as well as pressure-treated wood assemblies are highly flammable. Consequently, we recommend the use of residential roofing systems that have Class A fire protection for the homeowner. Because residential roof fires remain a life-threatening danger to residential homeowners in the United States, we describe a national fire prevention program for reducing residential roof fires by use of an Underwriters Laboratories Inc. (UL) and National Fire Protection Association Class A fire-rated roof system.

  8. Roofs--Their Problems and Solutions.

    ERIC Educational Resources Information Center

    Swentkofske, Carl J.

    Most roofs are meant to withstand the elements for a period of 20 years; to achieve this goal, however, school officials must believe in a dedicated maintenance program and sell it to their superiors and school boards. Establishment of a school district roof maintenance program is explained. Job qualifications and training methods for an inhouse…

  9. A&M. TAN607 sections. Section A shows variable roof lines, variable ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    A&M. TAN-607 sections. Section A shows variable roof lines, variable thickness of hot shop shield walls, relationship of subterranean pool to grade. Section B shows relative heights of hot shop floor and its control gallery, position of bridge cranes and manipulator rails. Locomotive service pit. Referent drawing is ID-33-E-158 Above. Ralph M. Parsons 902-3-ANP-607-A 105. Date: December 1952. Approved by INEEL Classification Office for public release. INEEL index code no. 034-0607-00-693-106757 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

  10. 25 CFR 900.70 - What elements are included in the compensation for a lease entered into between the Secretary and...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) Fire safety system; (vii) Security system; and (viii) Roof, foundation, walls, floors. (12) Unscheduled...) Monitoring and preventive maintenance of building structures and systems, including but not limited to: (i..., repainting); (14) Security services; (15) Management fees; and (16) Other reasonable and necessary operation...

  11. Retractable Roof Greenhouses and Shadehouses

    Treesearch

    Jr. Bartok

    2005-01-01

    Open-roof greenhouses provide a natural environment for plant growth when the outdoor weather is suitable and an artificial environment when it is too hot or cold. Opening the roof over the plants increases light intensity, which can help to control the growth habit, flowering, and crop timing. It also reduces electricity costs because expensive fan cooling is not...

  12. Experimental Polyurethane Foam Roof Systems - II.

    DTIC Science & Technology

    1983-01-01

    distribution unlimited. qt’, B 11 1 A F FN 1 5.6,-’ ,". I Rf- IE I0 Edthat, I.f "" Roofs, energy conservation, insulation, sprayed polyurethane foam...pcriod is presented, and thle energy savings realized by Oamning thle roof’ are prese nted. Libirary Card Naval Civil lFiginvee.ig I alora tor)i...the energy savings I reali/ed by foaming the roof are presented.I Unclassified rC~U~tTY CL ASSIrICATIO)N OF THISt PAGi-h WI-., . I -d CONTENTS Page

  13. Eco-Environmental Factors in Green Roof Application in Indian Cities

    NASA Astrophysics Data System (ADS)

    Mukherjee, M.

    2014-09-01

    Green-roof is the cost-effective environmental mitigation strategy for urban areas [1]. Its application is limited in India primarily due to inadequate understanding about its cost-benefit analysis and technicalities of its maintenance. Increasing awareness about green roof can alter conservative attitude towards its application. So, this work presents a quantified study on green-roof types, cost and environmental benefits while considering different geo-urban climate scenarios for cities of Kolkata, Mumbai, Chennai and New Delhi. Cost estimation for extensive and intensive green-roof with reference to commonly used roof in urban India is also worked out. Attributes considered for environmental discussion are energy savings related to thermal heat gain through roof, roof-top storm-water drainage and sound attenuation. The comparative study confirms that further focused study on individual cities would identify city-specific objectives for green-roof application; strategies like awareness, capacity building programmes, incentives, demonstration projects etc. can be worked out accordingly for wider application of green-roof in Indian cities.

  14. 40 CFR 65.44 - External floating roof (EFR).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... external floating roof except for automatic bleeder vents (vacuum breaker vents) and rim space vents does... floating roof shall meet the following specifications: (i) Except for automatic bleeder vents (vacuum breaker vents) and rim space vents, each opening in the noncontact external floating roof shall provide a...

  15. 40 CFR 65.44 - External floating roof (EFR).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... external floating roof except for automatic bleeder vents (vacuum breaker vents) and rim space vents does... floating roof shall meet the following specifications: (i) Except for automatic bleeder vents (vacuum breaker vents) and rim space vents, each opening in the noncontact external floating roof shall provide a...

  16. 40 CFR 65.44 - External floating roof (EFR).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... external floating roof except for automatic bleeder vents (vacuum breaker vents) and rim space vents does... floating roof shall meet the following specifications: (i) Except for automatic bleeder vents (vacuum breaker vents) and rim space vents, each opening in the noncontact external floating roof shall provide a...

  17. Software for roof defects recognition on aerial photographs

    NASA Astrophysics Data System (ADS)

    Yudin, D.; Naumov, A.; Dolzhenko, A.; Patrakova, E.

    2018-05-01

    The article presents information on software for roof defects recognition on aerial photographs, made with air drones. An areal image segmentation mechanism is described. It allows detecting roof defects – unsmoothness that causes water stagnation after rain. It is shown that HSV-transformation approach allows quick detection of stagnation areas, their size and perimeters, but is sensitive to shadows and changes of the roofing-types. Deep Fully Convolutional Network software solution eliminates this drawback. The tested data set consists of the roofing photos with defects and binary masks for them. FCN approach gave acceptable results of image segmentation in Dice metric average value. This software can be used in inspection automation of roof conditions in the production sector and housing and utilities infrastructure.

  18. Comparative life cycle assessment of standard and green roofs.

    PubMed

    Saiz, Susana; Kennedy, Christopher; Bass, Brad; Pressnail, Kim

    2006-07-01

    Life cycle assessment (LCA) is used to evaluate the benefits, primarily from reduced energy consumption, resulting from the addition of a green roof to an eight story residential building in Madrid. Building energy use is simulated and a bottom-up LCA is conducted assuming a 50 year building life. The key property of a green roof is its low solar absorptance, which causes lower surface temperature, thereby reducing the heat flux through the roof. Savings in annual energy use are just over 1%, but summer cooling load is reduced by over 6% and reductions in peak hour cooling load in the upper floors reach 25%. By replacing the common flat roof with a green roof, environmental impacts are reduced by between 1.0 and 5.3%. Similar reductions might be achieved by using a white roof with additional insulation for winter, but more substantial reductions are achieved if common use of green roofs leads to reductions in the urban heat island.

  19. Computer supplies insulation recipe for Cookie Company Roof

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    Roofing contractors no longer have to rely on complicated calculations and educated guesses to determine cost-efficient levels of roof insulation. A simple hand-held calculator and printer offers seven different programs for fast figuring insulation thickness based on job type, roof size, tax rates, and heating and cooling cost factors.

  20. Wall Finishes; Carpentry: 901895.

    ERIC Educational Resources Information Center

    Dade County Public Schools, Miami, FL.

    The course outline is designed to provide instruction in selecting, preparing, and installing wall finishing materials. Prerequisites for the course include mastery of building construction plans, foundations and walls, and basic mathematics. Intended for use in grades 11 and 12, the course contains five blocks of study totaling 135 hours of…

  1. Estimation of Solar Energy on Vertical 3D Building Walls on City Quarter Scale

    NASA Astrophysics Data System (ADS)

    Jaugsch, F.; Löwner, M.-O.

    2016-10-01

    In urban areas, solar energy is one promising source of renewable energy to achieve the EU parliament's goal of reducing CO2 emissions by 20 % compared to 1990. Although annual radiation on vertical walls is lower than that on roof surfaces, they are larger in area and, therefore may contribute to energy production. On the other hand, the modelling of shadowing effects is cost intensive in an complex urban environment. Here we present a method for the calculation of solar potential on vertical walls for simple 2D maps with additional building height information. We introduced observer point columns that enable a fast decision whether a whole vertical set of observer points is illuminated or not. By the introduction of a maximum shade length, we reduce processing time in ArcGIS. 206,291 points of 130 buildings have been analysed in time steps of 15 minutes resulting in 15 769 pairs of solar angles. Results disprove the potential of vertical walls serving to fill the winter gap of roof mounted solar energy plants. Best wall orientation for the deployment of solar panels are west and east in summer, whereas it is southeast in winter.

  2. Potential benefits of plant diversity on vegetated roofs: a literature review.

    PubMed

    Cook-Patton, Susan C; Bauerle, Taryn L

    2012-09-15

    Although vegetated green roofs can be difficult to establish and maintain, they are an increasingly popular method for mitigating the negative environmental impacts of urbanization. Most green roof development has focused on maximizing green roof performance by planting one or a few drought-tolerant species. We present an alternative approach, which recognizes green roofs as dynamic ecosystems and employs a diversity of species. We draw links between the ecological and green roof literature to generate testable predictions about how increasing plant diversity could improve short- and long-term green roof functioning. Although we found few papers that experimentally manipulated diversity on green roofs, those that did revealed ecological dynamics similar to those in more natural systems. However, there are many unresolved issues. To improve overall green roof performance, we should (1) elucidate the links among plant diversity, structural complexity, and green roof performance, (2) describe feedback mechanisms between plant and animal diversity on green roofs, (3) identify species with complementary traits, and (4) determine whether diverse green roof communities are more resilient to disturbance and environmental change than less diverse green roofs. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Effectiveness of Cool Roof Coatings with Ceramic Particles

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brehob, Ellen G; Desjarlais, Andre Omer; Atchley, Jerald Allen

    2011-01-01

    Liquid applied coatings promoted as cool roof coatings, including several with ceramic particles, were tested at Oak Ridge National Laboratory (ORNL), Oak Ridge, Tenn., for the purpose of quantifying their thermal performances. Solar reflectance measurements were made for new samples and aged samples using a portable reflectometer (ASTM C1549, Standard Test Method for Determination of Solar Reflectance Near Ambient Temperature Using a Portable Solar Reflectometer) and for new samples using the integrating spheres method (ASTM E903, Standard Test Method for Solar Absorptance, Reflectance, and Transmittance of Materials Using Integrating Spheres). Thermal emittance was measured for the new samples using amore » portable emissometer (ASTM C1371, Standard Test Method for Determination of Emittance of Materials Near Room 1 Proceedings of the 2011 International Roofing Symposium Temperature Using Portable Emissometers). Thermal conductivity of the coatings was measured using a FOX 304 heat flow meter (ASTM C518, Standard Test Method for Steady-State Thermal Transmission Properties by Means of the Heat Flow Meter Apparatus). The surface properties of the cool roof coatings had higher solar reflectance than the reference black and white material, but there were no significant differences among coatings with and without ceramics. The coatings were applied to EPDM (ethylene propylene diene monomer) membranes and installed on the Roof Thermal Research Apparatus (RTRA), an instrumented facility at ORNL for testing roofs. Roof temperatures and heat flux through the roof were obtained for a year of exposure in east Tennessee. The field tests showed significant reduction in cooling required compared with the black reference roof (~80 percent) and a modest reduction in cooling compared with the white reference roof (~33 percent). The coating material with the highest solar reflectivity (no ceramic particles) demonstrated the best overall thermal performance (combination of

  4. The Geometric Theory of Roof Reflector Resonators

    DTIC Science & Technology

    1976-12-01

    reflector, if properly oriented, (The terms "roof-top prism ," "right-angle prism ," and - incorrectly - " Porro prism " are encountered in .the literature...Q-switch prisms ) in laser resonators have been infrequent compared to the attention given spherical mirrors. This chapter summarizes the relevant...designator (Refs 42 and 43). In one experiment, a 900 roof prism was tested in a resonator with a 70% reflecting filat mirror. Thus, in Fig. 2, the right roof

  5. Roof Weakening of Hydraulic Fracturing for Control of Hanging Roof in the Face End of High Gassy Coal Longwall Mining: A Case Study

    NASA Astrophysics Data System (ADS)

    Huang, Bingxiang; Wang, Youzhuang

    2016-09-01

    The occurence of hanging roof commonly arises in the face end of longwall coal mining under hard roof conditions. The sudden break and subsequent caving of a hanging roof could result in the extrusion of gas in the gob to the face, causing gas concentrations to rise sharply and to increase to over a safety-limited value. A series of linear fracturing-holes of 32 mm diameter were drilled into the roof of the entries with an anchor rig. According to the theory that the gob should be fully filled with the fragmentized falling roof rock, the drilling depth is determined as being 3 5 times the mining height if the broken expansion coefficient takes an empirical value. Considering the general extension range of cracks and the supporting form of the entryway, the spacing distance between two drilling holes is determined as being 1 2 times the crack's range of extension. Using a mounting pipe, a high pressure resistant sealing device of a small diameter-size was sent to the designated location for the high-pressure hydraulic fracturing of the roof rock. The hydraulic fracturing created the main hydro-fracturing crack and airfoil branch cracks in the interior of the roof-rock, transforming the roof structure and weakening the strength of the roof to form a weak plane which accelerated roof caving, and eventually induced the full caving in of the roof in time with the help of ground pressure. For holes deeper than 4 m, retreating hydraulic fracturing could ensure the uniformity of crack extension. Tested and applied at several mines in Shengdong Mining District, the highest ruptured water pressure was found to be 55 MPa, and the hanging roof at the face end was reduced in length from 12 m to less than 1 2 m. This technology has eliminated the risk of the extrusion of gas which has accumulated in the gob.

  6. ETR, TRA642. WALL SECTION DETAILS. METAL SIDING JOINS TO ELECTRICAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    ETR, TRA-642. WALL SECTION DETAILS. METAL SIDING JOINS TO ELECTRICAL BUILDING, OFFICE BUILDING, AND ROOF. KAISER ETR-5528-MTR-A-13, 11/1955. INL INDEX NO. 532-0642-00-486-100920, REV. 4. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  7. Hygrothermal Performance of West Coast Wood Deck Roofing System

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pallin, Simon B.; Kehrer, Manfred; Desjarlais, Andre Omer

    2014-02-01

    Simulations of roofing assemblies are necessary in order to understand and adequately predict actual the hygrothermal performance. At the request of GAF, simulations have been setup to verify the difference in performance between white and black roofing membrane colors in relation to critical moisture accumulation for traditional low slope wood deck roofing systems typically deployed in various western U.S. Climate Zones. The performance of these roof assemblies has been simulated in the hygrothermal calculation tool of WUFI, from which the result was evaluated based on a defined criterion for moisture safety. The criterion was defined as the maximum accepted watermore » content for wood materials and the highest acceptable moisture accumulation rate in relation to the risk of rot. Based on the criterion, the roof assemblies were certified as being either safe, risky or assumed to fail. The roof assemblies were simulated in different western climates, with varying insulation thicknesses, two different types of wooden decking, applied with varying interior moisture load and with either a high or low solar absorptivity at the roof surface (black or white surface color). The results show that the performance of the studied roof assemblies differs with regard to all of the varying parameters, especially the climate and the indoor moisture load.« less

  8. 30 CFR 75.220 - Roof control plan.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... measures shall be taken to protect persons if unusual hazards are encountered. (2) The proposed roof... revisions to a roof control plan are proposed, only the revised pages need to be submitted unless otherwise...

  9. 30 CFR 75.220 - Roof control plan.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... measures shall be taken to protect persons if unusual hazards are encountered. (2) The proposed roof... revisions to a roof control plan are proposed, only the revised pages need to be submitted unless otherwise...

  10. 30 CFR 75.220 - Roof control plan.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... measures shall be taken to protect persons if unusual hazards are encountered. (2) The proposed roof... revisions to a roof control plan are proposed, only the revised pages need to be submitted unless otherwise...

  11. Life-cycle cost-benefit analysis of extensive vegetated roof systems.

    PubMed

    Carter, Timothy; Keeler, Andrew

    2008-05-01

    The built environment has been a significant cause of environmental degradation in the previously undeveloped landscape. As public and private interest in restoring the environmental integrity of urban areas continues to increase, new construction practices are being developed that explicitly value beneficial environmental characteristics. The use of vegetation on a rooftop--commonly called a green roof--as an alternative to traditional roofing materials is an increasingly utilized example of such practices. The vegetation and growing media perform a number of functions that improve environmental performance, including: absorption of rainfall, reduction of roof temperatures, improvement in ambient air quality, and provision of urban habitat. A better accounting of the green roof's total costs and benefits to society and to the private sector will aid in the design of policy instruments and educational materials that affect individual decisions about green roof construction. This study uses data collected from an experimental green roof plot to develop a benefit cost analysis (BCA) for the life cycle of extensive (thin layer) green roof systems in an urban watershed. The results from this analysis are compared with a traditional roofing scenario. The net present value (NPV) of this type of green roof currently ranges from 10% to 14% more expensive than its conventional counterpart. A reduction of 20% in green roof construction cost would make the social NPV of the practice less than traditional roof NPV. Considering the positive social benefits and relatively novel nature of the practice, incentives encouraging the use of this practice in highly urbanized watersheds are strongly recommended.

  12. Using Remote Sensing to Quantify Roof Albedo in Seven California Cities

    NASA Astrophysics Data System (ADS)

    Ban-Weiss, G. A.; Woods, J.; Millstein, D.; Levinson, R.

    2013-12-01

    Cool roofs reflect sunlight and therefore can reduce cooling energy use in buildings. Further, since roofs cover about 20-25% of cities, wide spread deployment of cool roofs could mitigate the urban heat island effect and partially counter urban temperature increases associated with global climate change. Accurately predicting the potential for increasing urban albedo using reflective roofs and its associated energy use and climate benefits requires detailed knowledge of the current stock of roofs at the city scale. Until now this knowledge has been limited due to a lack of availability of albedo data with sufficient spatial coverage, spatial resolution, and spectral information. In this work we use a novel source of multiband aerial imagery to derive the albedos of individual roofs in seven California cities: Los Angeles, Long Beach, San Diego, Bakersfield, Sacramento, San Francisco, and San Jose. The radiometrically calibrated, remotely sensed imagery has high spatial resolution (1 m) and four narrow (less than 0.1 μm wide) band reflectances: blue, green, red, and near-infrared. To derive the albedo of roofs in each city, we first locate roof pixels within GIS building outlines. Next we use laboratory measurements of the solar spectral reflectances of 190 roofing products to empirically relate solar reflectance (albedo) to reflectances in the four narrow bands; the root-mean-square of the residuals for the albedo prediction is 0.016. Albedos computed from remotely sensed reflectances are calibrated to ground measurements of roof albedo in each city. The error (both precision and accuracy) of albedo values is presented for each city. The area-weighted mean roof albedo (× standard deviation) for each city ranges from 0.17 × 0.08 (Los Angeles) to 0.29 × 0.15 (San Diego). In each city most roofs have low albedo in the range of 0.1 to 0.3. Roofs with albedo greater than 0.4 comprise less than 3% of total roofs and 7% of total roof area in each city. The California

  13. Photovoltaic roofing tile systems

    NASA Astrophysics Data System (ADS)

    Melchior, B.

    The integration of photovoltaic (PV) systems in architecture is discussed. A PV-solar roofing tile system with polymer concrete base; PV-roofing tile with elastomer frame profiles and aluminum profile frames; contact technique; and solar cell modules measuring technique are described. Field tests at several places were conducted on the solar generator, electric current behavior, battery station, electric installation, power conditioner, solar measuring system with magnetic bubble memory technique, data transmission via telephone modems, and data processing system. The very favorable response to the PV-compact system proves the commercial possibilities of photovoltaic integration in architecture.

  14. Fuel consumption impacts of auto roof racks

    DOE PAGES

    Chen, Yuche; Meier, Alan

    2016-03-23

    The after-market roof rack is one of the most common components attached to a vehicle for carrying over-sized items, such as bicycles and skis. It is important to understand these racks' fuel consumption impacts on both individual vehicles and the national fleet because they are widely used. We estimate the national fuel consumption impacts of roof racks using a bottom-up approach. Our model incorporates real-world data and vehicle stock information to enable assessing fuel consumption impacts for several categories of vehicles, rack configurations, and usage conditions. In addition, the model draws on two new data-gathering techniques, on-line forums and crowd-sourcing.more » The results show that nationwide, roof racks are responsible for 0.8‰ of light duty vehicle fuel consumption in 2015, corresponding to 100 million gallons of gasoline per year. Sensitivity analyses show that results are most sensitive to the fraction of vehicles with installed roof racks but carrying no equipment. Here, the aerodynamic efficiency of typical roof racks can be greatly improved and reduce individual vehicle fuel consumption; however, government policies to minimize extensive driving with empty racks--if successful--could save more fuel nationally.« less

  15. The effect of roofing material on the quality of harvested rainwater.

    PubMed

    Mendez, Carolina B; Klenzendorf, J Brandon; Afshar, Brigit R; Simmons, Mark T; Barrett, Michael E; Kinney, Kerry A; Kirisits, Mary Jo

    2011-02-01

    Due to decreases in the availability and quality of traditional water resources, harvested rainwater is increasingly used for potable and non-potable purposes. In this study, we examined the effect of conventional roofing materials (i.e., asphalt fiberglass shingle, Galvalume(®) metal, and concrete tile) and alternative roofing materials (i.e., cool and green) on the quality of harvested rainwater. Results from pilot-scale and full-scale roofs demonstrated that rainwater harvested from any of these roofing materials would require treatment if the consumer wanted to meet United States Environmental Protection Agency primary and secondary drinking water standards or non-potable water reuse guidelines; at a minimum, first-flush diversion, filtration, and disinfection are recommended. Metal roofs are commonly recommended for rainwater harvesting applications, and this study showed that rainwater harvested from metal roofs tends to have lower concentrations of fecal indicator bacteria as compared to other roofing materials. However, concrete tile and cool roofs produced harvested rainwater quality similar to that from the metal roofs, indicating that these roofing materials also are suitable for rainwater harvesting applications. Although the shingle and green roofs produced water quality comparable in many respects to that from the other roofing materials, their dissolved organic carbon concentrations were very high (approximately one order of magnitude higher than what is typical for a finished drinking water in the United States), which might lead to high concentrations of disinfection byproducts after chlorination. Furthermore the concentrations of some metals (e.g., arsenic) in rainwater harvested from the green roof suggest that the quality of commercial growing media should be carefully examined if the harvested rainwater is being considered for domestic use. Hence, roofing material is an important consideration when designing a rainwater catchment. Copyright

  16. DOE ZERH Case Study: Sunroc Builders, Bates Avenue, Lakeland, FL

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    none,

    2015-09-01

    Case study of a DOE 2015 Housing Innovation Award winning affordable home in the hot-humid climate that got HERS 57 without PV, with 6.5” SIP walls and 8.25” SIP roof; uninsulated slab foundation; fresh air intake; SEER 16 ducted air source heat pump.

  17. INTERIOR VIEW OF SOUTHWEST WALL OF SECOND FLOOR SHOWING WINDOWS, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW OF SOUTHWEST WALL OF SECOND FLOOR SHOWING WINDOWS, SLIDING DOORS AND METAL ROOF FRAMING. VIEW FACING SOUTHWEST - U.S. Naval Base, Pearl Harbor, Ford Island Polaris Missile Lab & U.S. Fleet Ballistic Missile Submarine Training Center, Between Lexington Boulvevard and the sea plane ramps on the southwest side of Ford Island, Pearl City, Honolulu County, HI

  18. Experimental analysis of green roof substrate detention characteristics.

    PubMed

    Yio, Marcus H N; Stovin, Virginia; Werdin, Jörg; Vesuviano, Gianni

    2013-01-01

    Green roofs may make an important contribution to urban stormwater management. Rainfall-runoff models are required to evaluate green roof responses to specific rainfall inputs. The roof's hydrological response is a function of its configuration, with the substrate - or growing media - providing both retention and detention of rainfall. The objective of the research described here is to quantify the detention effects due to green roof substrates, and to propose a suitable hydrological modelling approach. Laboratory results from experimental detention tests on green roof substrates are presented. It is shown that detention increases with substrate depth and as a result of increasing substrate organic content. Model structures based on reservoir routing are evaluated, and it is found that a one-parameter reservoir routing model coupled with a parameter that describes the delay to start of runoff best fits the observed data. Preliminary findings support the hypothesis that the reservoir routing parameter values can be defined from the substrate's physical characteristics.

  19. Experimental Polyvinyl Chloride (PVC) Roofing: Field Test Results.

    DTIC Science & Technology

    1987-02-01

    construction. These were the single-ply membranes of the ethylene-propylene-diene monomer ( EPDM ) and polyvinyl chloride (PVC) types, and the sprayed-in-place...polyurethane foam (PUF) with an elastomeric coating. EPDM and PUF roofs were constructed in 19802 and the PVC roofs were completed during summer 1983...faced isocyanu- rate foam board in two layers . Roofing systems were installed loose-laid and ballasted. Specific membrane materials were Plymouth

  20. 40 CFR 443.30 - Applicability; description of the asphalt roofing subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... asphalt roofing subcategory. 443.30 Section 443.30 Protection of Environment ENVIRONMENTAL PROTECTION... ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Roofing Subcategory § 443.30 Applicability; description of the asphalt roofing subcategory. The provisions of this subpart are applicable to...

  1. 40 CFR 443.30 - Applicability; description of the asphalt roofing subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... asphalt roofing subcategory. 443.30 Section 443.30 Protection of Environment ENVIRONMENTAL PROTECTION... ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Roofing Subcategory § 443.30 Applicability; description of the asphalt roofing subcategory. The provisions of this subpart are applicable to...

  2. 40 CFR 443.30 - Applicability; description of the asphalt roofing subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... asphalt roofing subcategory. 443.30 Section 443.30 Protection of Environment ENVIRONMENTAL PROTECTION... ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Roofing Subcategory § 443.30 Applicability; description of the asphalt roofing subcategory. The provisions of this subpart are applicable to...

  3. OPTIMIZING GREEN ROOF TECHNOLOGIES IN THE MIDWEST

    EPA Science Inventory

    Green roofs, while extensively used in Europe, are an emerging technology in the U.S. They have an array of potential benefits (including improved storm water management, increased energy conservation of buildings, reduced urban heat island effects, and extended roof life) ...

  4. Home advantage in retractable-roof baseball stadia.

    PubMed

    Romanowich, Paul

    2012-10-01

    This study examined whether the home advantage varies for open-air, domed, or retractable-roof baseball stadia, and whether having the roof open or closed affects the home advantage in retractable-roof baseball stadia. Data from Major League Baseball (MLB) games played between 2001 and 2009 were analyzed for whether or not the presence of a home-advantage was dependent on the type of home stadium used. Home advantage was robust for all three types of stadia. A significant effect of stadium type on home advantage was found, with a greater home advantage for teams playing home games in domed stadia relative to open-air stadia, replicating a previous study. There was a greater home advantage for teams playing home games in domed stadia relative to retractable-roof stadia. No other differences in the home advantage were found; results are discussed in terms of familiarity with the facility.

  5. Impact of roof height non-uniformity on pollutant transport between a street canyon and intersections.

    PubMed

    Nosek, Štěpán; Kukačka, Libor; Jurčáková, Klára; Kellnerová, Radka; Jaňour, Zbyněk

    2017-08-01

    This paper presents an extension of our previous wind-tunnel study (Nosek et al., 2016) in which we highlighted the need for investigation of the removal mechanisms of traffic pollution from all openings of a 3D street canyon. The extension represents the pollution flux (turbulent and advective) measurements at the lateral openings of three different 3D street canyons for the winds perpendicular and oblique to the along-canyon axis. The pollution was simulated by emitting a passive gas (ethane) from a homogeneous ground-level line source positioned along the centreline of the investigated street canyons. The street canyons were formed by courtyard-type buildings of two different regular urban-array models. The first model has a uniform building roof height, while the second model has a non-uniform roof height along each building's wall. The mean flow and concentration fields at the canyons' lateral openings confirm the findings of other studies that the buildings' roof-height variability at the intersections plays an important role in the dispersion of the traffic pollutants within the canyons. For the perpendicular wind, the non-uniform roof-height canyon appreciably removes or entrains the pollutant through its lateral openings, contrary to the uniform canyon, where the pollutant was removed primarily through the top. The analysis of the turbulent mass transport revealed that the coherent flow structures of the lateral momentum transport correlate with the ventilation processes at the lateral openings of all studied canyons. These flow structures coincide at the same areas and hence simultaneously transport the pollutant in opposite directions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Roofer: An Engineered Management System (EMS) for Bituminous Built-Up Roofs

    DTIC Science & Technology

    1989-12-01

    individual roof projects. Figure 1 shows an example of a filing sequence for a typical recordkceping system. The file should contain a Building Folder ...for each building and a Roof Section Foldcr for each roof section on the building. Building Folder The Building Folder should contain a completed...should also be kept in the building folder , or if they are kept elsewhere, their location should be stated in the folder . Roof Section Folder A Roof

  7. Metal Roofing in a "Class" by Itself.

    ERIC Educational Resources Information Center

    Nimtz, Paul D.

    1990-01-01

    The structural standing seam roof has the advantages of ease of application, low maintenance, and low life-cycle costs. Explains and illustrates how the system's concealed clip attachments are designed so that the roof panels can expand and contract independently of the insulation. (MLF)

  8. Green roof systems: a study of public attitudes and preferences in southern Spain.

    PubMed

    Fernandez-Cañero, Rafael; Emilsson, Tobias; Fernandez-Barba, Carolina; Herrera Machuca, Miguel Ángel

    2013-10-15

    This study investigates people's preconceptions of green roofs and their visual preference for different green roof design alternatives in relation to behavioral, social and demographical variables. The investigation was performed as a visual preference study using digital images created to represent eight different alternatives: gravel roof, extensive green roof with Sedums not in flower, extensive green roof with sedums in bloom, semi-intensive green roof with sedums and ornamental grasses, semi-intensive green roof with shrubs, intensive green roof planted with a lawn, intensive green roof with succulent and trees and intensive green roof with shrubs and trees. Using a Likert-type scale, 450 respondents were asked to indicate their preference for each digital image. Results indicated that respondents' sociodemographic characteristics and childhood environmental background influenced their preferences toward different green roof types. Results also showed that green roofs with a more careful design, greater variety of vegetation structure, and more variety of colors were preferred over alternatives. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. The "Brick Wall" Graphic Organizer

    ERIC Educational Resources Information Center

    Matteson, Shirley M.

    2016-01-01

    A brick wall provides a fitting description of what happens when teachers try to teach a concept for which students are unprepared. When students are unsuccessful academically, their foundational knowledge may be missing, incomplete, or incorrect. As a result, students "hit a brick wall," and their academic progress stops because they do…

  10. Architectural Drafting, Drafting 2: 9255.04.

    ERIC Educational Resources Information Center

    Dade County Public Schools, Miami, FL.

    The course covers the basic fundamentals of architectural drafting and is not intended to delve into the more advanced phases of architecture. The student is presented with standards and procedures, and will become proficient in layout of floor plans, electrical plans, roof construction, foundation plans, typical wall construction, plot plans, and…

  11. Measure Guideline: Three High Performance Mineral Fiber Insulation Board Retrofit Solutions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Neuhauser, K.

    2015-01-01

    This Measure Guideline describes a high performance enclosure retrofit package that uses mineral fiber insulation board, and is intended to serve contractors and designers seeking guidance for non-foam exterior insulation retrofit processes. The guideline describes retrofit assembly and details for wood frame roof and walls and for cast concrete foundations.

  12. ACL Roof Impingement Revisited: Does the Independent Femoral Drilling Technique Avoid Roof Impingement With Anteriorly Placed Tibial Tunnels?

    PubMed

    Tanksley, John A; Werner, Brian C; Conte, Evan J; Lustenberger, David P; Burrus, M Tyrrell; Brockmeier, Stephen F; Gwathmey, F Winston; Miller, Mark D

    2017-05-01

    Anatomic femoral tunnel placement for single-bundle anterior cruciate ligament (ACL) reconstruction is now well accepted. The ideal location for the tibial tunnel has not been studied extensively, although some biomechanical and clinical studies suggest that placement of the tibial tunnel in the anterior part of the ACL tibial attachment site may be desirable. However, the concern for intercondylar roof impingement has tempered enthusiasm for anterior tibial tunnel placement. To compare the potential for intercondylar roof impingement of ACL grafts with anteriorly positioned tibial tunnels after either transtibial (TT) or independent femoral (IF) tunnel drilling. Controlled laboratory study. Twelve fresh-frozen cadaver knees were randomized to either a TT or IF drilling technique. Tibial guide pins were drilled in the anterior third of the native ACL tibial attachment site after debridement. All efforts were made to drill the femoral tunnel anatomically in the center of the attachment site, and the surrogate ACL graft was visualized using 3-dimensional computed tomography. Reformatting was used to evaluate for roof impingement. Tunnel dimensions, knee flexion angles, and intra-articular sagittal graft angles were also measured. The Impingement Review Index (IRI) was used to evaluate for graft impingement. Two grafts (2/6, 33.3%) in the TT group impinged upon the intercondylar roof and demonstrated angular deformity (IRI type 1). No grafts in the IF group impinged, although 2 of 6 (66.7%) IF grafts touched the roof without deformation (IRI type 2). The presence or absence of impingement was not statistically significant. The mean sagittal tibial tunnel guide pin position prior to drilling was 27.6% of the sagittal diameter of the tibia (range, 22%-33.9%). However, computed tomography performed postdrilling detected substantial posterior enlargement in 2 TT specimens. A significant difference in the sagittal graft angle was noted between the 2 groups. TT grafts were

  13. The influence of extensive vegetated roofs on runoff water quality.

    PubMed

    Berndtsson, Justyna Czemiel; Emilsson, Tobias; Bengtsson, Lars

    2006-02-15

    The influence of extensive sedum-moss vegetated roofs on runoff water quality was studied for four full scale installations located in southern Sweden. The aim of the study was to ascertain whether the vegetated roof behaves as a sink or a source of pollutants and whether the age of a vegetated roof influences runoff quality. The runoff quality from vegetated roofs was also compared with the runoff quality from non-vegetated roofs located in study areas. The following metals and nutrients were investigated: Cd, Cr, Cu, Fe, K, Mn, Pb, Zn, NO3-N, NH4-N, Tot-N, PO4-P, and Tot-P. The results show that, with the exception of nitrogen, vegetated roofs behave as source of contaminants. While in lower concentrations than normally found in urban runoff, some metals appear in concentrations that would correspond to moderately polluted natural water. Nitrate nitrogen is retained by the vegetation or soil or both. Apart from the oldest, the studied vegetated roofs contribute phosphate phosphorus to the runoff. The maintenance of the vegetation systems on the roofs has to be carefully designed in order to avoid storm-water contamination; for instance, the use of easily dissolvable fertilizers should be avoided.

  14. Effect of age and rainfall pH on contaminant yields from metal roofs.

    PubMed

    Wicke, Daniel; Cochrane, Thomas A; O'Sullivan, Aisling D; Cave, Simon; Derksen, Mark

    2014-01-01

    Metal roofs are recognized for conveying significant metal loads to urban streams through stormwater runoff. Metal concentrations in urban runoff depend on roof types and prevailing weather conditions but the combined effects of roof age and rainfall pH on metal mobilization are not well understood. To investigate these effects on roof runoff, water quality was analysed from galvanized iron and copper roofs following rainfall events and also from simulating runoff using a rainfall simulator on specially constructed roof modules. Zinc and copper yields under different pH regimes were investigated for two roof materials and two different ages. Metal mobilization from older roofs was greater than new roofs with 55-year-old galvanized roof surfaces yielding more Zn, on average increasing by 45% and 30% under a rainfall pH of 4 and 8, respectively. Predominantly dissolved (85-95%) Zn and Cu concentrations in runoff exponentially increased as the rainfall pH decreased. Results also confirmed that copper guttering and downpipes associated with galvanized steel roof systems can substantially increase copper levels in roof runoff. Understanding the dynamics of roof surfaces as a function of weathering and rainfall pH regimes can help developers with making better choices about roof types and materials for stormwater improvement.

  15. Effects of Solar Photovoltaic Panels on Roof Heat Transfer

    NASA Technical Reports Server (NTRS)

    Dominguez, A.; Klessl, J.; Samady, M.; Luvall, J. C.

    2010-01-01

    Building Heating, Ventilation and Air Conditioning (HVAC) is a major contributor to urban energy use. In single story buildings with large surface area such as warehouses most of the heat enters through the roof. A rooftop modification that has not been examined experimentally is solar photovoltaic (PV) arrays. In California alone, several GW in residential and commercial rooftop PV are approved or in the planning stages. With the PV solar conversion efficiency ranging from 5-20% and a typical installed PV solar reflectance of 16-27%, 53-79% of the solar energy heats the panel. Most of this heat is then either transferred to the atmosphere or the building underneath. Consequently solar PV has indirect effects on roof heat transfer. The effect of rooftop PV systems on the building roof and indoor energy balance as well as their economic impacts on building HVAC costs have not been investigated. Roof calculator models currently do not account for rooftop modifications such as PV arrays. In this study, we report extensive measurements of a building containing a flush mount and a tilted solar PV array as well as exposed reference roof. Exterior air and surface temperature, wind speed, and solar radiation were measured and thermal infrared (TIR) images of the interior ceiling were taken. We found that in daytime the ceiling surface temperature under the PV arrays was significantly cooler than under the exposed roof. The maximum difference of 2.5 C was observed at around 1800h, close to typical time of peak energy demand. Conversely at night, the ceiling temperature under the PV arrays was warmer, especially for the array mounted flat onto the roof. A one dimensional conductive heat flux model was used to calculate the temperature profile through the roof. The heat flux into the bottom layer was used as an estimate of the heat flux into the building. The mean daytime heat flux (1200-2000 PST) under the exposed roof in the model was 14.0 Watts per square meter larger than

  16. Specifying, Installing and Maintaining Built-Up and Modified Bitumen Roofing Systems.

    ERIC Educational Resources Information Center

    Hobson, Joseph W.

    2000-01-01

    Examines built-up, modified bitumen, and hybrid combinations of the two roofing systems and offers advise on how to assure high- quality performance and durability when using them. Included is a glossary of commercial roofing terms and asphalt roofing resources to aid in making decisions on roofing and systems product selection. (GR)

  17. A Review of Methods for the Manufacture of Residential Roofing Materials

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Akbari, Hashem; Levinson, Ronnen; Berdahl, Paul

    2003-06-01

    Shingles, tiles, and metal products comprise over 80% (by roof area) of the California roofing market (54-58% fiberglass shingle, 8-10% concrete tile, 8-10% clay tile, 7% metal, 3% wood shake, and 3% slate). In climates with significant demand for cooling energy, increasing roof solar reflectance reduces energy consumption in mechanically cooled buildings, and improves occupant comfort in non-conditioned buildings. This report examines methods for manufacturing fiberglass shingles, concrete tiles, clay tiles, and metal roofing. The report also discusses innovative methods for increasing the solar reflectance of these roofing materials. We have focused on these four roofing products because they aremore » typically colored with pigmented coatings or additives. A better understanding of the current practices for manufacturing colored roofing materials would allow us to develop cool colored materials creatively and more effectively.« less

  18. Roof selection for rainwater harvesting: quantity and quality assessments in Spain.

    PubMed

    Farreny, Ramon; Morales-Pinzón, Tito; Guisasola, Albert; Tayà, Carlota; Rieradevall, Joan; Gabarrell, Xavier

    2011-05-01

    Roofs are the first candidates for rainwater harvesting in urban areas. This research integrates quantitative and qualitative data of rooftop stormwater runoff in an urban Mediterranean-weather environment. The objective of this paper is to provide criteria for the roof selection in order to maximise the availability and quality of rainwater. Four roofs have been selected and monitored over a period of 2 years (2008-2010): three sloping roofs - clay tiles, metal sheet and polycarbonate plastic - and one flat gravel roof. The authors offer a model for the estimation of the runoff volume and the initial abstraction of each roof, and assess the physicochemical contamination of roof runoff. Great differences in the runoff coefficient (RC) are observed, depending mostly on the slope and the roughness of the roof. Thus, sloping smooth roofs (RC>0.90) may harvest up to about 50% more rainwater than flat rough roofs (RC=0.62). Physicochemical runoff quality appears to be generally better than the average quality found in the literature review (conductivity: 85.0 ± 10.0 μS/cm, total suspended solids: 5.98 ± 0.95 mg/L, total organic carbon: 11.6 ± 1.7 mg/L, pH: 7.59 ± 0.07 upH). However, statistically significant differences are found between sloping and flat rough roofs for some parameters (conductivity, total organic carbon, total carbonates system and ammonium), with the former presenting better quality in all parameters (except for ammonium). The results have an important significance for local governments and urban planners in the (re)design of buildings and cities from the perspective of sustainable rainwater management. The inclusion of criteria related to the roof's slope and roughness in city planning may be useful to promote rainwater as an alternative water supply while preventing flooding and water scarcity. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Operation UPSHOT-KNOTHOLE, Nevada Proving Grounds, March-June 1953. Project 3.5 Tests on the Response of Wall and Roof Panels and the Transmission of Load to Supporting Structure

    DTIC Science & Technology

    1955-05-01

    56 4.23 Postshot, 3.5ba, Interior of Test Cell . . . . . . . . • • 57 4.24 Postshot, 35.Sbb, Damage to Precast Concrete Channel Roof 6...Predicted Applied and Measured Transmitted Forces, Roof Panel 3.5bb (3-1/2 in. precast concrete channels on steel purlins) . . . o . o . ... . ... 104 5.16...truss rafters 3.Sba Bowstring truss with wood 4500 4200 10 7.1 10 decking, tar and gravel roofing 3.5bb 3-1/2 in. precast concrete channels on steel

  20. Demonstration of Three Corrosion-Resistant Sustainable Roofing Systems

    DTIC Science & Technology

    2013-06-01

    will significantly im- prove upon the performance of the original roofing systems . Improvement of energy efficiency, drainage , and other attributes...Sustainable Roofing Systems Final Report on Project F08-AR02 Co ns tr uc tio n En gi ne er in g R es ea rc h La bo ra to ry David M. Bailey...CERL TR-13-7 June 2013 Demonstration of Three Corrosion-Resistant Sustainable Roofing Systems Final Report on Project F08-AR02 David M. Bailey

  1. Composition and Diversity of Avian Communities Using a New Urban Habitat: Green Roofs

    NASA Astrophysics Data System (ADS)

    Washburn, Brian E.; Swearingin, Ryan M.; Pullins, Craig K.; Rice, Matthew E.

    2016-06-01

    Green roofs on buildings are becoming popular and represent a new component of the urban landscape. Public benefits of green roof projects include reduced stormwater runoff, improved air quality, reduced urban heat island effects, and aesthetic values. As part of a city-wide plan, several green roofs have been constructed at Chicago's O'Hare International Airport (ORD). Like some other landscaping features, green roofs on or near an airport might attract wildlife and thus increase the risk of bird-aircraft collisions. During 2007-2011, we conducted a series of studies to evaluate wildlife use of newly constructed green roofs and traditional (gravel) roofs on buildings at ORD. These green roofs were 0.04-1.62 ha in area and consisted of primarily stonecrop species for vegetation. A total of 188 birds were observed using roofs during this research. Of the birds using green roofs, 66, 23, and 4 % were Killdeer, European Starlings, and Mourning Doves, respectively. Killdeer nested on green roofs, whereas the other species perched, foraged, or loafed. Birds used green roofs almost exclusively between May and October. Overall, avian use of the green roofs was minimal and similar to that of buildings with traditional roofs. Although green roofs with other vegetation types might offer forage or cover to birds and thus attract potentially hazardous wildlife, the stonecrop-vegetated green roofs in this study did not increase the risk of bird-aircraft collisions.

  2. Composition and Diversity of Avian Communities Using a New Urban Habitat: Green Roofs.

    PubMed

    Washburn, Brian E; Swearingin, Ryan M; Pullins, Craig K; Rice, Matthew E

    2016-06-01

    Green roofs on buildings are becoming popular and represent a new component of the urban landscape. Public benefits of green roof projects include reduced stormwater runoff, improved air quality, reduced urban heat island effects, and aesthetic values. As part of a city-wide plan, several green roofs have been constructed at Chicago's O'Hare International Airport (ORD). Like some other landscaping features, green roofs on or near an airport might attract wildlife and thus increase the risk of bird-aircraft collisions. During 2007-2011, we conducted a series of studies to evaluate wildlife use of newly constructed green roofs and traditional (gravel) roofs on buildings at ORD. These green roofs were 0.04-1.62 ha in area and consisted of primarily stonecrop species for vegetation. A total of 188 birds were observed using roofs during this research. Of the birds using green roofs, 66, 23, and 4 % were Killdeer, European Starlings, and Mourning Doves, respectively. Killdeer nested on green roofs, whereas the other species perched, foraged, or loafed. Birds used green roofs almost exclusively between May and October. Overall, avian use of the green roofs was minimal and similar to that of buildings with traditional roofs. Although green roofs with other vegetation types might offer forage or cover to birds and thus attract potentially hazardous wildlife, the stonecrop-vegetated green roofs in this study did not increase the risk of bird-aircraft collisions.

  3. Green Roofs: Federal Energy Management Program (FEMP) Federal Technology Alert

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Scholz-Barth, K.; Tanner, S.

    In a ''green roof,'' a layer of vegetation (e.g., a roof garden) covers the surface of a roof to provide shade, cooler indoor and outdoor temperatures, and effective storm-water management to reduce runoff. The main components are waterproofing, soil, and plants. There are two basic kinds: intensive and extensive. An intensive green roof often features large shrubs and trees, and it can be expensive to install and maintain. An extensive green roof features shallow soil and low-growing, horizontally spreading plants that can thrive in the alpine conditions of many rooftops. These plants do not require a lot of water ormore » soil, and they can tolerate a significant amount of exposure to the sun and wind. This Federal Technology Alert focuses on the benefits, design, and implementation of extensive green roofs and includes criteria for their use on federal facilities.« less

  4. High-Performance Slab-on-Grade Foundation Insulation Retrofits

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Goldberg, Louise F.; Mosiman, Garrett E.

    A more accurate assessment of slab-on-grade foundation insulation energy savings than traditionally possible is now feasible. This has been enabled by advances in whole building energy simulation with 3-dimensional foundation modelling integration at each time step together with an experimental measurement of the site energy savings of SOG foundation insulation. Ten SOG insulation strategies were evaluated on a test building to identify an optimum retrofit insulation strategy in a zone 6 climate (Minneapolis, MN). The optimum insulation strategy in terms of energy savings and cost effectiveness consisted of two components: (a) R-20 XPS insulation above grade, and, (b) R-20 insulationmore » at grade (comprising an outer layer of R-10 insulation and an interior layer of R-12 poured polyurethane insulation) tapering to R-10 XPS insulation at half the below-grade wall height (the lower half of the stem wall was uninsulated).« less

  5. Storm Water Retention on Three Green Roofs with Distinct Climates

    NASA Astrophysics Data System (ADS)

    Breach, P. A.; Sims, A.; O'Carroll, D. M.; Robinson, C. E.; Smart, C. C.; Powers, B. S. C.

    2014-12-01

    As urbanization continues to increase the impact of cities on their surrounding environments, the feasibility of implementing low-impact development such as green roofs is of increasing interest. Green roofs retain and attenuate storm water thereby reducing the load on urban sewer systems. In addition, green roofs can provide insulation and lower roof surface temperature leading to a decrease in building energy load. Green roof technology in North American urban environments remains underused, in part due to a lack of climate appropriate green roof design guidelines. The capacity of a green roof to moderate runoff depends on the storage capacity of the growing medium at the start of a rainfall event. Storage capacity is finite, which makes rapid drainage and evapotranspiration loss critical for maximizing storage capacity between subsequent storms. Here the retention and attenuation of storm events are quantified for experimental green roof sites located in three representative Canadian climates corresponding to; semiarid conditions in Calgary, Alberta, moderate conditions in London, Ontario, and cool and humid conditions in Halifax, Nova Scotia. The storage recovery and storm water retention at each site is modelled using a modified water balance approach. Components of the water balance including evapotranspiration are predicted using climate data collected from 2012 to 2014 at each of the experimental sites. During the measurement period there were over 300 precipitation events ranging from small, frequent events (< 2 mm) to a storm with a 250 year return period. The modeling approach adopted provides a tool for planners to assess the feasibility of implementing green roofs in their respective climates.

  6. 47. VIEW ON THE ROOF, LOOKING EAST TO WEST FROM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    47. VIEW ON THE ROOF, LOOKING EAST TO WEST FROM THE SOUTHWEST CORNER OF THE MAIN ROOF (NOTE CHIMNEY TO NORTH & PEAK OF METAL ROOF COVERING THE EAST SIDE BAY OF OCTAGONAL ROOMS) - Kenworthy Hall, State Highway 14 (Greensboro Road), Marion, Perry County, AL

  7. Fourier analysis of conductive heat transfer for glazed roofing materials

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Roslan, Nurhana Lyana; Bahaman, Nurfaradila; Almanan, Raja Noorliyana Raja

    For low-rise buildings, roof is the most exposed surface to solar radiation. The main mode of heat transfer from outdoor via the roof is conduction. The rate of heat transfer and the thermal impact is dependent on the thermophysical properties of roofing materials. Thus, it is important to analyze the heat distribution for the various types of roofing materials. The objectives of this paper are to obtain the Fourier series for the conductive heat transfer for two types of glazed roofing materials, namely polycarbonate and polyfilled, and also to determine the relationship between the ambient temperature and the conductive heatmore » transfer for these materials. Ambient and surface temperature data were collected from an empirical field investigation in the campus of Universiti Teknologi MARA Shah Alam. The roofing materials were installed on free-standing structures in natural ventilation. Since the temperature data are generally periodic, Fourier series and numerical harmonic analysis are applied. Based on the 24-point harmonic analysis, the eleventh order harmonics is found to generate an adequate Fourier series expansion for both glazed roofing materials. In addition, there exists a linear relationship between the ambient temperature and the conductive heat transfer for both glazed roofing materials. Based on the gradient of the graphs, lower heat transfer is indicated through polyfilled. Thus polyfilled would have a lower thermal impact compared to polycarbonate.« less

  8. Effect of roof strength in injury mitigation during pole impact.

    PubMed

    Friedman, Keith; Hutchinson, John; Mihora, Dennis; Kumar, Sri; Frieder, Russell; Sances, Anthony

    2007-01-01

    Motor vehicle accidents involving pole impacts often result in serious head and neck injuries to occupants. Pole impacts are typically associated with rollover and side collisions. During such events, the roof structure is often deformed into the occupant survival space. The existence of a strengthened roof structure would reduce roof deformation and accordingly provide better protection to occupants. The present study examines the effect of reinforced (strengthened) roofs using experimental crash study and computer model simulation. The experimental study includes the production cab structure of a pickup truck. The cab structure was loaded using an actual telephone pole under controlled laboratory conditions. The cab structure was subjected to two separate load conditions at the A-pillar and door frame. The contact force and deformation were measured using a force gauge and potentiometer, respectively. A computer finite element model was created to simulate the experimental studies. The results of finite element model matched well with experimental data during two different load conditions. The validated finite element model was then used to simulate a reinforced roof structure. The reinforced roof significantly reduced the structural deformations compared to those observed in the production roof. The peak deformation was reduced by approximately 75% and peak velocity was reduced by approximately 50%. Such a reduction in the deformation of the roof structure helps to maintain a safe occupant survival space.

  9. Engine room, showing engine generator foundation and inlet louvers, looking ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Engine room, showing engine generator foundation and inlet louvers, looking southwest. Note fuel gauge on west wall, left of fuse box, and exhaust pipe through south wall. - Western Union Telegraph Company, Jennerstown Relay, Laurel Summit Road off U.S. 30, Laughlintown, Westmoreland County, PA

  10. Minimal watering regime impacts on desert adapted green roof plant performance

    NASA Astrophysics Data System (ADS)

    Kovachich, S.; Pavao-Zuckerman, M.; Templer, S.; Livingston, M.; Stoltz, R.; Smith, S.

    2011-12-01

    Roof tops can cover one-fifth of urban areas and can greatly alter the movement of matter and energy in cities. With traditional roofing methods and materials, roof tops readily absorb heat and as a result, buildings and the surrounding urban area heat to unnaturally high temperatures. It is hypothesized that extensive green roofs would have wide-ranging benefits for arid environments. However, little is known about the cost of water use associated with green roof installations and how to balance energy reduction needs with water costs in this water limited environment. We are conducting a pilot study to test whether a) green roofs with native plants and environmentally-responsible watering regimes will prove successful in arid environments and if b) green roofs provide ecosystem services with responsible water application. Three species of Sonoran Desert natives, Dyssodia pentachaeta (groundcover), Calliandra eriophylla (shrub), and Hesperaloe parviflora (succulent) have been planted in experimental plots [1 m2 model houses and roofs, replicated in triplicate] with two sandy, rocky desert soil mixtures (light mix: 60% expanded shale and heavy mix: organic and sandy mix with 50% shale) at the Biosphere 2 campus near Oracle, Az. The green roofs are watered by two different techniques. The first technique provides "smart watering", the minimal amount of water needed by green roof plants based on precipitation and historical data. The second watering technique is considered heavy and does not take into account environmental conditions. Preliminary data from the experimental plots shows a 30% decrease in daytime roof top temperatures on green roofs and a 10% decrease in interior temperatures in buildings with green roofs. This trend occurs with both watering regimes (heavy and light). This finding suggests that additional irrigation yields no extra heat reduction and energy savings. In order to explain this phenomenon more clearly, we use co-located temperature and

  11. Measure Guideline: Three High Performance Mineral Fiber Insulation Board Retrofit Solutions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Neuhauser, Ken

    2015-01-01

    This Measure Guideline describes a high performance enclosure retrofit package that uses mineral fiber insulation board. The Measure Guideline describes retrofit assembly and details for wood frame roof and walls and for cast concrete foundations. This Measure Guideline is intended to serve contractors and designers seeking guidance for non-foam exterior insulation retrofit.

  12. Field Testing Unvented Roofs with Asphalt Shingles in Cold and Hot-Humid Climates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ueno, Kohta; Lstiburek, Joseph W.

    2015-09-01

    Insulating roofs with dense-pack cellulose (instead of spray foam) has moisture risks, but is a lower cost approach. If moisture risks could be addressed, buildings could benefit from retrofit options, and the ability to bring HVAC systems within the conditioned space. Test houses with unvented roof assemblies were built to measure long-term moisture performance, in the Chicago area (5A) and the Houston area (2A). The Chicago-area test bed had seven experimental rafter bays, including a control vented compact roof, and six unvented roof variants with cellulose or fiberglass insulation. The interior was run at 50% RH. All roofs except themore » vented cathedral assembly experienced wood moisture contents and RH levels high enough to constitute failure. Disassembly at the end of the experiment showed that the unvented fiberglass roofs had wet sheathing and mold growth. In contrast, the cellulose roofs only had slight issues, such as rusted fasteners and sheathing grain raise. The Houston-area roof was an unvented attic insulated with spray-applied fiberglass. Most ridges and hips were built with a diffusion vent detail, capped with vapor permeable roof membrane. Some ridge sections were built as a conventional unvented roof, as a control. In the control unvented roofs, roof peak RHs reached high levels in the first winter; as exterior conditions warmed, RHs quickly fell. In contrast, the diffusion vent roofs had drier conditions at the roof peak in wintertime, but during the summer, RHs and MCs were higher than the unvented roof (albeit in the safe range).« less

  13. Rainwater runoff retention on an aged intensive green roof.

    PubMed

    Speak, A F; Rothwell, J J; Lindley, S J; Smith, C L

    2013-09-01

    Urban areas are characterised by large proportions of impervious surfaces which increases rainwater runoff and the potential for surface water flooding. Increased precipitation is predicted under current climate change projections, which will put further pressure on urban populations and infrastructure. Roof greening can be used within flood mitigation schemes to restore the urban hydrological balance of cities. Intensive green roofs, with their deeper substrates and higher plant biomass, are able to retain greater quantities of runoff, and there is a need for more studies on this less common type of green roof which also investigate the effect of factors such as age and vegetation composition. Runoff quantities from an aged intensive green roof in Manchester, UK, were analysed for 69 rainfall events, and compared to those on an adjacent paved roof. Average retention was 65.7% on the green roof and 33.6% on the bare roof. A comprehensive soil classification revealed the substrate, a mineral soil, to be in good general condition and also high in organic matter content which can increase the water holding capacity of soils. Large variation in the retention data made the use of predictive regression models unfeasible. This variation arose from complex interactions between Antecedant Dry Weather Period (ADWP), season, monthly weather trends, and rainfall duration, quantity and peak intensity. However, significantly lower retention was seen for high rainfall events, and in autumn, which had above average rainfall. The study period only covers one unusually wet year, so a longer study may uncover relationships to factors which can be applied to intensive roofs elsewhere. Annual rainfall retention for Manchester city centre could be increased by 2.3% by a 10% increase in intensive green roof construction. The results of this study will be of particular interest to practitioners implementing greenspace adaptation in temperate and cool maritime climates. Copyright © 2013

  14. Development of the trickle roof cooling and heating system: Experimental plan

    NASA Astrophysics Data System (ADS)

    Haves, P.; Jankovic, T.; Doderer, E.

    1982-07-01

    A passive system applicable both to retrofit and new construction was developed. This system (the trickle roof system) dissipates heat from a thin film of water flowing over the roof. A small scale trickle roof system dissipator was tested at Trinity University under a range of ambient conditions and operating configurations. The results suggest that trickle roof systems should have comparable performance to roof pond systems. Provided is a review of the trickle roof system concept, several possible configurations, and the benefits the systems can provide. Test module experiments And results are presented in detail. The requirements for full scale testing are discussed and a plan is outlined using the two identical residential scale passive test facility buildings at Trinity University, San Antonio, Texas. Full scale experimental results would be used to validate computer algorithms, provide system optimization, and produce a nationwide performance assessment and design guidelines. This would provide industry with the information necessary to determine the commerical potential of the trickle roof system.

  15. Inclusion of cool roofs in nonresidential Title 24 prescriptive requirements

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Levinson, Ronnen; Akbari, Hashem; Konopacki, Steve

    2002-12-15

    Roofs that have high solar reflectance (high ability to reflect sunlight) and high thermal emittance (high ability to radiate heat) tend to stay cool in the sun. The same is true of low-emittance roofs with exceptionally high solar reflectance. Substituting a cool roof for a noncool roof tends to decrease cooling electricity use, cooling power demand, and cooling-equipment capacity requirements, while slightly increasing heating energy consumption. Cool roofs can also lower the ambient air temperature in summer, slowing ozone formation and increasing human comfort. DOE-2.1E building energy simulations indicate that use of a cool roofing material on a prototypical Californiamore » nonresidential building with a low-sloped roof yields average annual cooling energy savings of approximately 300 kWh/1000 ft2 [3.2 kWh/m2], average annual natural gas deficits of 4.9 therm/1000 ft2 [5.6 MJ/m2], average source energy savings of 2.6 MBTU/1000 ft2 [30 MJ/m2], and average peak power demand savings of 0. 19 kW/1000 ft2 [2.1 W/m2]. The 15-year net present value (NPV) of energy savings averages $450/1000 ft2 [$4.90/m2] with time dependent valuation (TDV), and $370/1000 ft2 [$4.00/m2] without TDV. When cost savings from downsizing cooling equipment are included, the average total savings (15-year NPV + equipment savings) rises to $550/1000 ft2 [$5.90/m2] with TDV, and to $470/1000 ft2 [$5.00/m2] without TDV. Total savings range from 0.18 to 0.77 $/ft2 [1.90 to 8.30 $/m2] with TDV, and from 0.16 to 0.66 $/ft2 [1.70 to 7.10 $/m2] without TDV, across California's 16 climate zones. The typical cost premium for a cool roof is 0.00 to 0.20 $/ft2 [0.00 to 2.20 $/m2]. Cool roofs with premiums up to $0.20/ft2 [$2.20/m2] are expected to be cost effective in climate zones 2 through 16; those with premiums not exceeding $0.18/ft2 [$1.90/m2] are expected to be also cost effective in climate zone 1. Hence, this study recommends that the year-2005 California building energy efficiency code

  16. Residential roof condition assessment system using deep learning

    NASA Astrophysics Data System (ADS)

    Wang, Fan; Kerekes, John P.; Xu, Zhuoyi; Wang, Yandong

    2018-01-01

    The emergence of high resolution (HR) and ultra high resolution (UHR) airborne remote sensing imagery is enabling humans to move beyond traditional land cover analysis applications to the detailed characterization of surface objects. A residential roof condition assessment method using techniques from deep learning is presented. The proposed method operates on individual roofs and divides the task into two stages: (1) roof segmentation, followed by (2) condition classification of the segmented roof regions. As the first step in this process, a self-tuning method is proposed to segment the images into small homogeneous areas. The segmentation is initialized with simple linear iterative clustering followed by deep learned feature extraction and region merging, with the optimal result selected by an unsupervised index, Q. After the segmentation, a pretrained residual network is fine-tuned on the augmented roof segments using a proposed k-pixel extension technique for classification. The effectiveness of the proposed algorithm was demonstrated on both HR and UHR imagery collected by EagleView over different study sites. The proposed algorithm has yielded promising results and has outperformed traditional machine learning methods using hand-crafted features.

  17. 49 CFR 238.123 - Emergency roof access.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... inches laterally. (b) Means of access. Emergency roof access shall be provided by means of a hatch, or a... a hatch, it shall be possible to push interior panels or liners out of their retention devices and into the interior of the vehicle after removing the hatch. If emergency roof access is provided by...

  18. 49 CFR 238.123 - Emergency roof access.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... inches laterally. (b) Means of access. Emergency roof access shall be provided by means of a hatch, or a... a hatch, it shall be possible to push interior panels or liners out of their retention devices and into the interior of the vehicle after removing the hatch. If emergency roof access is provided by...

  19. Stormwater quality from extensive green roofs in a subtropical region

    NASA Astrophysics Data System (ADS)

    Onis Pessoa, Jonas; Allasia, Daniel; Tassi, Rutineia; Vaz Viega, Juliana; Fensterseifer, Paula

    2016-04-01

    Green roofs have increasingly become an integral part of urban environments, mainly due to their aesthetic benefits, thermal comfort and efficiency in controlling excess runoff. However, the effects of this emerging technology in the qualitative characteristics of rainwater is still poorly understood. In this study was evaluated the effect of two different extensive green roofs (EGRs) and a traditional roof built with corrugated fiber cement sheets (control roof) in the quality of rainwater, in a subtropical climate area in the city of Santa Maria, in southern Brazil. The principal variant between the two EGRs were the type of plant species, time since construction, soil depth and the substrate characteristics. During the monitoring period of the experiment, between the months of April and December of 2015 fourteen rainfall events were selected for qualitative analysis of water from the three roofs and directly from rainfall. It was analyzed physical (turbidity, apparent color, true color, electrical conductivity, total solids, dissolved solids, suspended solids and temperature), chemical (pH, phosphate, total nitrogen, nitrate, nitrite, chloride, sulfate, BOD, iron and total hardness), heavy metals (copper, zinc, lead and chromium) and microbiological parameters (total coliforms and E. coli). It was also characterized the substrates used in both extensive green roofs. The results showed that the quality of the water drained from EGR s was directly influenced by their substrates (in turn containing significant levels of nutrients, organic matter and some metals). The passage of rainwater through green roofs and control roof resulted in the elevation of pH, allowing the conversion of the slightly acidic rainfall into basic water. Similarly, on both types of roofs occurred an increase of the values of most of the physical, chemical and microbiological parameters compared to rainwater. This same trend was observed for heavy metals, although with a much smaller degree

  20. Inclusion of cool roofs in nonresidential Title 24 prescriptiverequirements

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Levinson, Ronnen; Akbari, Hashem; Konopacki, Steve

    2003-07-01

    Roofs that have high solar reflectance (high ability toreflect sunlight) and high thermal emittance (high ability to radiateheat) tend to stay cool in the sun. The same is true of low-emittanceroofs with exceptionally high solar reflectance. Substituting a cool rooffor a non-cool roof tends to decrease cooling electricity use, coolingpower demand, and cooling-equipment capacity requirements, while slightlyincreasing heating energy consumption. Cool roofs can also lower citywideambient air temperature in summer, slowing ozone formation and increasinghuman comfort.DOE-2.1E building energy simulations indicate that use of acool roofing material on a prototypical California nonresidential (NR)building with a low-sloped roof yields average annual coolingmore » energysavings of approximately 3.2 kW h/m2 (300 kW h/1000 ft2), average annualnatural gas deficits of 5.6 MJ/m2 (4.9 therm/1000 ft2), average annualsource energy savings of 30 MJ/m2 (2.6 MBTU/1000 ft2), and average peakpower demand savings of 2.1 W/m2 (0.19 kW/1000 ft2). The 15-year netpresent value (NPV) of energy savings averages $4.90/m2 ($450/1000 ft2)with time-dependent valuation (TDV), and $4.00/m2 ($370/1000 ft2) withoutTDV. When cost savings from downsizing cooling equipment are included,the average total savings (15-year NPV+equipment savings) rises to$5.90/m2 ($550/1000 ft2) with TDV, and to $5.00/m2 ($470/1000 ft2)without TDV.Total savings range from 1.90 to 8.30 $/m2 (0.18 0.77 $/ft2)with TDV, and from 1.70 to 7.10 $/m2 (0.16 0.66 $/ft2) without TDV,across California's 16 climate zones. The typical cost premium for a coolroof is 0.00 2.20 $/m2 (0.00 0.20 $/ft2). Cool roofs with premiums up to$2.20/m2 ($0.20/ft2) are expected to be cost effective in climate zones 216; those with premiums not exceeding $1.90/m2 ($0.18/ft2) are expectedto be also cost effective in climate zone 1. Hence, this study recommendsthat the year-2005 California building energy efficiency code (Title 24,Part 6 of the California

  1. What You Should Know about Single-Ply Roofing.

    ERIC Educational Resources Information Center

    Szcygiel, Tony L.

    1998-01-01

    Explains why a single-ply roofing system is the best choice for educational facilities. It discusses how single-ply roofing systems offer flexibility with ease of application; cause less disruption during installation; and are clean, safe, and energy efficient. (GR)

  2. Modelling of green roofs' hydrologic performance using EPA's SWMM.

    PubMed

    Burszta-Adamiak, E; Mrowiec, M

    2013-01-01

    Green roofs significantly affect the increase in water retention and thus the management of rain water in urban areas. In Poland, as in many other European countries, excess rainwater resulting from snowmelt and heavy rainfall contributes to the development of local flooding in urban areas. Opportunities to reduce surface runoff and reduce flood risks are among the reasons why green roofs are more likely to be used also in this country. However, there are relatively few data on their in situ performance. In this study the storm water performance was simulated for the green roofs experimental plots using the Storm Water Management Model (SWMM) with Low Impact Development (LID) Controls module (version 5.0.022). The model consists of many parameters for a particular layer of green roofs but simulation results were unsatisfactory considering the hydrologic response of the green roofs. For the majority of the tested rain events, the Nash coefficient had negative values. It indicates a weak fit between observed and measured flow-rates. Therefore complexity of the LID module does not affect the increase of its accuracy. Further research at a technical scale is needed to determine the role of the green roof slope, vegetation cover and drying process during the inter-event periods.

  3. Field Testing Unvented Roofs with Asphalt Shingles in Cold and Hot-Humid Climates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ueno, Kohta; Lstiburek, Joseph W.

    2015-09-01

    Test houses with unvented roof assemblies were built to measure long-term moisture performance, in the Chicago area (5A) and the Houston area (2A). The Chicago-area test bed had seven experimental rafter bays, including a control vented compact roof, and six unvented roof variants with cellulose or fiberglass insulation. The interior was run at 50% RH. The Houston-area roof was an unvented attic insulated with spray-applied fiberglass. Most ridges and hips were built with a diffusion vent detail, capped with vapor permeable roof membrane. In contrast, the diffusion vent roofs had drier conditions at the roof peak in wintertime, but duringmore » the summer, RHs and MCs were higher than the unvented roof (albeit in the safe range).« less

  4. Urban heat mitigation by roof surface materials during the East Asian summer monsoon

    NASA Astrophysics Data System (ADS)

    Lee, Seungjoon; Ryu, Youngryel; Jiang, Chongya

    2017-04-01

    Roof surface materials, such as green and white roofs, have attracted attention in their role in urban heat mitigation, and various studies have assessed the cooling performance of roof surface materials during hot and sunny summer seasons. However, summers in the East Asian monsoon climate region are characterized by significant fluctuations in weather events, such as dry periods, heatwaves, and rainy and cloudy days. This study investigated the efficacy of different roof surface materials for heat mitigation, considering the temperatures both at and beneath the surface of the roof covering materials during a summer monsoon in Seoul, Korea. We performed continuous observations of temperature at and beneath the surface of the roof covering materials, and manual observation of albedo and the normalized difference vegetation index (NDVI) for a white roof, two green roofs (grass [Poa pratensis] and sedum [Sedum sarmentosum]), and a reference surface. Overall, the surface temperature of the white roof was significantly lower than that of the grass and sedum roofs (1.1 and 1.3°C), whereas the temperature beneath the surface of the white roof did not differ significantly from that of the grass and sedum roofs during the summer. The degree of cloudiness significantly modified the surface temperature of the white roof compared with that of the grass and sedum roofs, which depended on plant metabolisms. It was difficult for the grass to maintain its cooling ability without adequate watering management. After considering the cooling performance and maintenance efforts for different environmental conditions, we concluded that white roof performed better in urban heat mitigation than grass and sedum during the East Asian summer monsoon. Our findings will be useful in urban heat mitigation in the region.

  5. 40 CFR 427.60 - Applicability; description of the asbestos roofing subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... asbestos roofing subcategory. 427.60 Section 427.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos Roofing Subcategory § 427.60 Applicability; description of the asbestos roofing...

  6. 40 CFR 427.60 - Applicability; description of the asbestos roofing subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... asbestos roofing subcategory. 427.60 Section 427.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos Roofing Subcategory § 427.60 Applicability; description of the asbestos roofing...

  7. 40 CFR 427.60 - Applicability; description of the asbestos roofing subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... asbestos roofing subcategory. 427.60 Section 427.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos Roofing Subcategory § 427.60 Applicability; description of the asbestos roofing...

  8. Solar power roof shingle

    NASA Technical Reports Server (NTRS)

    Forestieri, A. F.; Ratajczak, A. F.; Sidorak, L. G.

    1975-01-01

    Silicon solar cell module provides both all-weather protection and electrical power. Module consists of array of circular silicon solar cells bonded to fiberglass substrate roof shingle with fluorinated ethylene propylene encapsulant.

  9. 40 CFR 427.60 - Applicability; description of the asbestos roofing subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... asbestos roofing subcategory. 427.60 Section 427.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos Roofing Subcategory § 427.60 Applicability; description of the asbestos roofing subcategory. The...

  10. 40 CFR 427.60 - Applicability; description of the asbestos roofing subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... asbestos roofing subcategory. 427.60 Section 427.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ASBESTOS MANUFACTURING POINT SOURCE CATEGORY Asbestos Roofing Subcategory § 427.60 Applicability; description of the asbestos roofing subcategory. The...

  11. The design, effectiveness and construction of passive-thermal-control roofing shingles

    NASA Astrophysics Data System (ADS)

    Wolf, L., Jr.

    1982-09-01

    The concept of a passive thermal control roofing shingle, which is a shingle that reflects the summer sun and absorbs the winter sun, is discussed. It is indicated that it is possible to design shingles for particular latitudes and styles of roof which absorb nearly all of the winter solar energy and reflect nearly all of the summer solar energy. Calculations of the energy savings and cost effectiveness of the passive thermal control roofing shingle indicate that it is most cost effective on all south facing pitched roofs regardless of heating fuel type, and on flat or east or west facing roofs that are heated with costly fuels such as electricity or heating oil. The shingle is most effective on poorly insulated structures. The feasibility of using the passive thermal control roofing shingle in conjunction with a heat pump to pump heat absorbed by the shingle into a well insulated structure is demonstrated. Construction of a variety of models of the passive thermal control roofing shingle illustrate numerous alternate methods of manufacture. A profile extruded, plastic, glazed shingle appears to be the most promising approach. Use of a glazed shingle can increase the effectiveness of the passive thermal control roofing shingle by reducing convective heat losses.

  12. IMPLEMENTATION OF GREEN ROOF SUSTAINABILITY IN ARID CONDITIONS

    EPA Science Inventory

    We successfully designed and fabricated accurately scaled prototypes of a green roof and a conventional white roof and began testing in simulated conditions of 115-70°F with relative humidity of 13%. The design parameters were based on analytical models created through ver...

  13. Evaluation of Green Roof Plants and Materials for Semi-Arid Climates

    EPA Science Inventory

    Abstract While green roof systems have proven to be highly effective in the evaporative cooling of buildings, reduction of roof top temperatures, protection of roof membranes from solar radiation degradation, reducing stormwater runoff, as well as beautification of the urban roo...

  14. Roofing: Don't Let What's Over Head Kill Your Bottom Line.

    ERIC Educational Resources Information Center

    Shannon, James W., Jr.

    1983-01-01

    A Colorado school district employs a professional consulting firm to give an unbiased opinion on the district's roofing needs. Built-up, single-ply, and modified asphalt roofing systems have all been utilized. Preventive maintenance keeps roofing bills to a minimum. (MLF)

  15. 5. VIEW OF VENTILATION HOUSES AND ROOF MONITOR FROM SOUTHEAST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. VIEW OF VENTILATION HOUSES AND ROOF MONITOR FROM SOUTHEAST CORNER OF ROOF. ROOF MONITOR WINDOWS HAVE BEEN INFILLED WITH BRICK. THE VENTILATION HOUSES ARE PART OF THE ORIGINAL CENTRAL AIR CONDITIONING SYSTEM AND CONTAINED AIR WASHERS, FANS AND OTHER HUMIDFYING EQUIPMENT FROM PARKS-CRAMER COMPANY OF FITCHBURG, MASSACHUSETTS. LOCATING THIS EQUIPMENT ON THE ROOF MADE IT UNNECESSARY TO CONSTRUCT A FULL BASEMENT, AND THEREFORE LOWERED CONSTRUCTION COSTS. THIS ARRANGEMENT ALSO PUT THE AIR CONDITIONING EQUIPMENT CLOSEST TO THE TOP FLOOR SPINNING ROOM, WHICH HAD THE GREATEST COOLING REQUIREMENTS. - Stark Mill, 117 Corinth Road, Hogansville, Troup County, GA

  16. Establishment and performance of an experimental green roof under extreme climatic conditions.

    PubMed

    Klein, Petra M; Coffman, Reid

    2015-04-15

    Green roofs alter the surface energy balance and can help in mitigating urban heat islands. However, the cooling of green roofs due to evapotranspiration strongly depends on the climatic conditions, and vegetation type and density. In the Southern Central Plains of the United States, extreme weather events, such as high winds, heat waves and drought conditions pose challenges for successful implementation of green roofs, and likely alter their standard performance. The National Weather Center Experimental Green Roof, an interdisciplinary research site established in 2010 in Norman, OK, aimed to investigate the ecological performance and surface energy balance of green roof systems. Starting in May 2010, 26 months of vegetation studies were conducted and the radiation balance, air temperature, relative humidity, and buoyancy fluxes were monitored at two meteorological stations during April-October 2011. The establishment of a vegetative community trended towards prairie plant dominance. High mortality of succulents and low germination of grasses and herbaceous plants contributed to low vegetative coverage. In this condition succulent diversity declined. Bouteloua gracilis and Delosperma cooperi showed typological dominance in harsh climatic conditions, while Sedum species experienced high mortality. The plant community diversified through volunteers such as Euphorbia maculate and Portulaca maculate. Net radiation measured at a green-roof meteorological station was higher than at a control station over the original, light-colored roofing material. These findings indicate that the albedo of the green roof was lower than the albedo of the original roofing material. The low vegetative coverage during the heat and drought conditions in 2011, which resulted in the dark substrate used in the green roof containers being exposed, likely contributed to the low albedo values. Nevertheless, air temperatures and buoyancy fluxes were often lower over the green roof indicating

  17. Justification of the estimation technique for the technical condition of the tank with inadmissible imperfections in the wall shape

    NASA Astrophysics Data System (ADS)

    Chepur, Petr; Tarasenko, Alexander; Gruchenkova, Alesya

    2017-10-01

    The paper has its focus on the problem of estimating the stress-strain state of the vertical steel tanks with the inadmissible geometric imperfections in the wall shape. In the paper, the authors refer to an actual tank to demonstrate that the use of certain design schemes can lead to the raw errors and, accordingly, to the unreliable results. Obviously, these design schemes cannot be based on when choosing the real repair technologies. For that reason, authors performed the calculations of the tank removed out of service for the repair, basing on the developed finite-element model of the VST-5000 tank with a conical roof. The proposed approach was developed for the analysis of the SSS (stress-strain state) of a tank having geometric imperfections of the wall shape. Based on the work results, the following was proposed: to amend the Annex A methodology “Method for calculating the stress-strain state of the tank wall during repair by lifting the tank and replacing the wall metal structures” by inserting the requirement to compulsory consider the actual stiffness of the VST entire structure and its roof when calculating the structure stress-strain state.

  18. 40 CFR 443.30 - Applicability; description of the asphalt roofing subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... asphalt roofing subcategory. 443.30 Section 443.30 Protection of Environment ENVIRONMENTAL PROTECTION... MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Roofing Subcategory § 443.30 Applicability; description of the asphalt roofing subcategory. The provisions of this subpart are applicable to discharges...

  19. 40 CFR 443.30 - Applicability; description of the asphalt roofing subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... asphalt roofing subcategory. 443.30 Section 443.30 Protection of Environment ENVIRONMENTAL PROTECTION... MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Asphalt Roofing Subcategory § 443.30 Applicability; description of the asphalt roofing subcategory. The provisions of this subpart are applicable to discharges...

  20. Comparison of software models for energy savings from cool roofs

    DOE PAGES

    New, Joshua; Miller, William A.; Huang, Yu; ...

    2015-06-07

    For this study, a web-based Roof Savings Calculator (RSC) has been deployed for the United States Department of Energy as an industry-consensus tool to help building owners, manufacturers, distributors, contractors and researchers easily run complex roof and attic simulations. RSC simulates multiple roof and attic technologies for side-by-side comparison including reflective roofs, different roof slopes, above sheathing ventilation, radiant barriers, low-emittance roof surfaces, duct location, duct leakage rates, multiple substrate types, and insulation levels. Annual simulations of hour-by-hour, whole-building performance are used to provide estimated annual energy and cost savings from reduced HVAC use. While RSC reported similar cooling savingsmore » to other simulation engines, heating penalty varied significantly. RSC results show reduced cool roofing cost-effectiveness, thus mitigating expected economic incentives for this countermeasure to the urban heat island effect. This paper consolidates comparison of RSC's projected energy savings to other simulation engines including DOE-2.1E, AtticSim, Micropas, and EnergyPlus. Also included are comparisons to previous simulation-based studies, analysis of RSC cooling savings and heating penalties, the role of radiative heat exchange in an attic assembly, and changes made for increased accuracy of the duct model. Finally, radiant heat transfer and duct interaction not previously modeled is considered a major contributor to heating penalties.« less

  1. Nutrient leaching from extensive green roofs with different substrate compositions: a laboratory study.

    PubMed

    Zhang, Wei; Zhong, Xing; Che, Wu

    2018-02-01

    To investigate nutrient leaching from extensive green roofs, green roof platforms were established to investigate the effluent quantity and quality during artificial rainfall. When the influent volume reached three times the empty bed volume, for which the cumulative rainfall was around 300 mm, the effluent TP and COD concentrations of green roof platforms filled with peat soil did not tend to stabilize. For a long-term operation, the substrate depths had little significant influence on TN, TP and COD concentrations of the green roof effluents. A normalized cumulative emission process method was proposed to discuss the difference in various pollutant leaching processes. Obvious differences in the leaching process of different contaminants for green roof platforms filled with various substrates were observed. For the green roof filled with modified substrates, the nitrogen and phosphorus pollutant leaching rates were relatively high in the initial stage of green roof operation and the phosphorus leaching rate was higher than that of nitrogen. The green roof is a sink for TN, but not for TP and COD in this study. The outcomes are critical for the selection of green roof substrates and also contribute to green roof maintenance.

  2. Thermal performance of a Concrete Cool Roof under different climatic conditions of Mexico

    DOE PAGES

    Hernández-Pérez, I.; Álvarez, G.; Gilbert, H.; ...

    2014-11-27

    A cool roof is an ordinary roof with a reflective coating on the exterior surface which has a high solar reflectance and high thermal emittance. These properties let the roof keep a lower temperature than a standard roof under the same conditions. In this work, the thermal performance of a concrete roof with and without insulation and with two colors has been analyzed using the finite volume method. The boundary conditions of the external roof surface were taken from hourly averaged climatic data of four cities. For the internal surface, it is considered that the building is air-conditioned and themore » inside air has a constant temperature. The interior surface temperature and the heat flux rates into the roofs were obtained for two consecutive days in order to assess the benefits of a cool roofs in different climates.« less

  3. Developing resilient green roofs in a dry climate.

    PubMed

    Razzaghmanesh, M; Beecham, S; Brien, C J

    2014-08-15

    Living roofs are an emerging green infrastructure technology that can potentially be used to ameliorate both climate change and urban heat island effects. There is not much information regarding the design of green roofs for dry climates and so the aim of this study was to develop low maintenance and unfertilized green roofs for a dry climate. This paper describes the effects of four important elements of green roofs namely slope, depth, growing media and plant species and their possible interactions in terms of plant growth responses in a dry climate. Sixteen medium-scale green roofs were set up and monitored during a one year period. This experiment consisted of twelve vegetated platforms and four non-vegetated platforms as controls. The design for the experiment was a split-split-plot design in which the factors Slope (1° and 25°) and Depth (100mm, 300 mm) were randomized to the platforms (main plots). Root depth and volume, average height of plants, final dry biomass and ground cover, relative growth rate, final dry shoot-root ratio, water use efficiency and leaf succulence were studied during a twelve month period. The results showed little growth of the plants in media type A, whilst the growth was significant in both media types B and C. On average, a 90% survival rate of plants was observed. Also the growth indices indicated that some plants can grow efficiently in the harsh environment created by green roofs in a dry climate. The root growth pattern showed that retained water in the drainage layer is an alternative source of water for plants. It was also shown that stormwater can be used as a source of irrigation water for green roofs during six months of the year at the study site. In summary, mild sloping intensive systems containing media type C and planted with either Chrysocephalum apiculatum or Disphyma crassifolium showed the best performance. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. National Grid Deep Energy Retrofit Pilot Program—Clark Residence

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    2010-03-30

    In this case study, Building Science Corporation partnered with local utility company, National Grid, Massachusetts homes. This project involved the renovation of a 18th century Cape-style building and achieved a super-insulated enclosure (R-35 walls, R-50+ roof, R-20+ foundation), extensive water management improvements, high-efficiency water heater, and state-of-the-art ventilation.

  5. Review of in-service moisture and temperature conditions in wood-frame buildings

    Treesearch

    Samuel V. Glass; Anton TenWolde

    2007-01-01

    This literature review reports in-service moisture and temperature conditions of floor, wall, and roof members of wood-frame buildings and exposed wood decks and permanent wood foundations. A wide variation exists in reported wood moisture content, spanning a range from as low as 2% to well above 30%. Relevant studies are summarized, and measured values of wood...

  6. 40 CFR 65.44 - External floating roof (EFR).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... design requirements. The owner or operator who elects to control storage vessel regulated material emissions by using an external floating roof shall comply with the design requirements listed in paragraphs (a)(1) through (3) of this section. (1) The external floating roof shall be designed to float on the...

  7. 40 CFR 65.44 - External floating roof (EFR).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... design requirements. The owner or operator who elects to control storage vessel regulated material emissions by using an external floating roof shall comply with the design requirements listed in paragraphs (a)(1) through (3) of this section. (1) The external floating roof shall be designed to float on the...

  8. Green Roofs: A Part of Green Infrastructure Strategy for Urban Areas

    EPA Science Inventory

    This is a presentation on the basics of green roof technology. The presentation highlights some of the recent ORD research projects on green roofs and provides insight for the end user as to the benefits for green roof technology. It provides links to currently available EPA rep...

  9. Monitoring of the Green Roofs Installation in Brno-City District, Czech Republic

    NASA Astrophysics Data System (ADS)

    Rebrova, Tatiana; Beckovsky, David; Selnik, Petr

    2017-12-01

    In spite of the rapidly growing interest to the green roofs, there is insufficient information about their local quantities and areas in Czech Republic as well as in Central Europe. There is a lack of technical information that leads to the further development, application and environmental contribution of green roofs under local climatic conditions. The purpose of the research is to follow the tendency of how the process of green roofs’ popularization is performed in the Czech Republic and to determine basic parameters of the installed green roofs. These parameters include total quantity, area and the most common roof vegetation type (extensive or intensive); how many green roofs were installed over the last years and as a result, how the proportion of the green roofs to the conventional ones is changing. For initial evaluation Brno-City District was chosen as the next stage of university environmental project EnviHUT following the genesis of green roofs under local weather conditions.

  10. The Equivalent Thermal Resistance of Tile Roofs with and without Batten Systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Miller, William A

    Clay and concrete tile roofs were installed on a fully instrumented attic test facility operating in East Tennessee s climate. Roof, attic and deck temperatures and heat flows were recorded for each of the tile roofs and also on an adjacent attic cavity covered with a conventionally pigmented and direct-nailed asphalt shingle roof. The data were used to benchmark a computer tool for simulation of roofs and attics and the tool used to develop an approach for computing an equivalent seasonal R-value for sub-tile venting. The approach computed equal heat fluxes through the ceilings of roofs having different combinations ofmore » surface radiation properties and or building constructions. A direct nailed shingle roof served as a control for estimating the equivalent thermal resistance of the air space. Simulations were benchmarked to data in the ASHRAE Fundamentals for the thermal resistance of inclined and closed air spaces.« less

  11. High Performance Slab-on-Grade Foundation Insulation Retrofits

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Goldberg, Louise F.; Mosiman, Garrett E.

    ?A more accurate assessment of SOG foundation insulation energy savings than traditionally possible is now feasible. This has been enabled by advances in whole building energy simulation with 3-dimensional foundation modelling integration at each time step together with an experimental measurement of the site energy savings of SOG foundation insulation. Ten SOG insulation strategies were evaluated on a test building to identify an optimum retrofit insulation strategy in a zone 6 climate (Minneapolis, MN). The optimum insulation strategy in terms of energy savings and cost effectiveness consisted of two components: (a) R-20 XPS insulation above grade, and, (b) R-20 insulationmore » at grade (comprising an outer layer of R-10 insulation and an interior layer of R-12 poured polyurethane insulation) tapering to R-10 XPS insulation at half the below-grade wall height (the lower half of the stem wall was uninsulated). The optimum insulation strategy was applied to single and multi-family residential buildings in climate zone 4 - 7. The highest site energy savings of 5% was realized for a single family home in Duluth, MN, and the lowest savings of 1.4 % for a 4-unit townhouse in Richmond, VA. SOG foundation insulation retrofit simple paybacks ranged from 18 to 47 years. There are other benefits of SOG foundation insulation resulting from the increase in the slab surface temperatures. These include increased occupant thermal comfort, and a decrease in slab surface condensation particularly around the slab perimeter.« less

  12. 113. ARAI Hot cell (ARA626) Building wall sections and details ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    113. ARA-I Hot cell (ARA-626) Building wall sections and details of radio chemistry lab. Shows high-bay roof over hot cells and isolation rooms below grade storage pit for fuel elements. Norman Engineering Company: 961-area/SF-626-A-4. Date: January 1959. Ineel index code no. 068-0626-00-613-102724. - Idaho National Engineering Laboratory, Army Reactors Experimental Area, Scoville, Butte County, ID

  13. 17. DETAIL OF INTERIOR AND EXTERIOR WALL CONSTRUCTION, VIEW TOWARD ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. DETAIL OF INTERIOR AND EXTERIOR WALL CONSTRUCTION, VIEW TOWARD NORTHEAST CORNER, THIRD BAY Showing insulated exterior wall at right; asphalt felt on interior separation wall at left; sill beam, stud, and concrete foundation detailing of interior wall. - U.S. Military Academy, Ice House, Mills Road at Howze Place, West Point, Orange County, NY

  14. 4 Living roofs in 3 locations: Does configuration affect runoff mitigation?

    NASA Astrophysics Data System (ADS)

    Fassman-Beck, Elizabeth; Voyde, Emily; Simcock, Robyn; Hong, Yit Sing

    2013-05-01

    Four extensive living roofs and three conventional (control) roofs in Auckland, New Zealand have been evaluated over periods of 8 months to over 2 yrs for stormwater runoff mitigation. Up to 56% cumulative retention was measured from living roofs with 50-150 mm depth substrates installed over synthetic drainage layers, and with >80% plant coverage. Variation in cumulative %-retention amongst sites is attributed to different durations of monitoring, rather than actual performance. At all sites, runoff rarely occurred at all from storms with less than 25 mm of precipitation, from the combined effects of substrates designed to maximize moisture storage and because >90% of individual events were less than 25 mm. Living roof runoff depth per event is predicted well by a 2nd order polynomial model (R2 = 0.81), again demonstrating that small storms are well managed. Peak flow per event from the living roofs was 62-90% less than a corresponding conventional roof's runoff. Seasonal retention performance decreased slightly in winter, but was nonetheless substantial, maintaining 66% retention at one site compared to 45-93% in spring-autumn at two sites. Peak flow mitigation did not vary seasonally. During a 4-month period of concurrent monitoring at all sites, varied substrate depth did not influence runoff depth (volume), %-retention, or %-peak flow mitigation compared to a control roof at the same site. The magnitude of peak flow was greater from garden shed-scale living roofs compared to the full-scale living roofs. Two design aspects that could be manipulated to increase peak flow mitigation include lengthening the flow path through the drainage layer to vertical gutters and use of flow-retarding drainage layer materials.

  15. A field study to evaluate runoff quality from green roofs.

    PubMed

    Vijayaraghavan, K; Joshi, U M; Balasubramanian, R

    2012-03-15

    Green (vegetated) roofs are emerging as practical strategies to improve the environmental quality of cities. However, the impact of green roofs on the storm water quality remains a topic of concern to city planners and environmental policy makers. This study investigated whether green roofs act as a source or a sink of various metals (Na, K, Ca, Mg, Al, Fe, Cu, Cd, Pb, Zn, Mn, Cr, Ni, Li and Co), inorganic anions (NO3-, NO2-, PO4(3-), SO4(2-), Cl-, F- and Br-) and cation (NH4+). A series of green roof assemblies were constructed. Four different real rain events and several artificial rain events were considered for the study. Results showed that concentrations of most of the chemical components in runoff were highest during the beginning of rain events and subsided in the subsequent rain events. Some of the important components present in the runoff include Na, K, Ca, Mg, Li, Fe, Al, Cu, NO3-, PO4(3-) and SO4(2-). However, the concentration of these chemical components in the roof runoff strongly depends on the nature of substrates used in the green roof and the volume of rain. Based on the USEPA standards for freshwater quality, we conclude that the green roof used in this study is reasonably effective except that the runoff contains significant amounts of NO3- and PO4(3-). Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Two-dimensional modeling of water and heat fluxes in green roof substrates

    NASA Astrophysics Data System (ADS)

    Suarez, F. I.; Sandoval, V. P.

    2016-12-01

    Due to public concern towards sustainable development, greenhouse gas emissions and energy efficiency, green roofs have become popular in the last years. Green roofs integrate vegetation into infrastructures to reach additional benefits that minimize negative impacts of the urbanization. A properly designed green roof can reduce environmental pollution, noise levels, energetic requirements or surface runoff. The correct performance of green roofs depends on site-specific conditions and on each component of the roof. The substrate and the vegetation layers strongly influence water and heat fluxes on a green roof. The substrate is an artificial media that has an improved performance compared to natural soils as it provides critical resources for vegetation survival: water, nutrients, and a growing media. Hence, it is important to study the effects of substrate properties on green roof performance. The objective of this work is to investigate how the thermal and hydraulic properties affect the behavior of a green roof through numerical modeling. The substrates that were investigated are composed by: crushed bricks and organic soil (S1); peat with perlite (S2); crushed bricks (S3); mineral soil with tree leaves (S4); and a mixture of topsoil and mineral soil (S5). The numerical model utilizes summer-arid meteorological information to evaluate the performance of each substrate. Results show that the area below the water retention curve helps to define the substrate that retains more water. In addition, the non-linearity of the water retention curve can increment the water needed to irrigate the roof. The heat propagation through the roof depends strongly on the hydraulic behavior, meaning that a combination of a substrate with low thermal conductivity and more porosity can reduce the heat fluxes across the roof. Therefore, it can minimize the energy consumed of an air-conditioner system.

  17. Producing superhydrophobic roof tiles.

    PubMed

    Carrascosa, Luis A M; Facio, Dario S; Mosquera, Maria J

    2016-03-04

    Superhydrophobic materials can find promising applications in the field of building. However, their application has been very limited because the synthesis routes involve tedious processes, preventing large-scale application. A second drawback is related to their short-term life under outdoor conditions. A simple and low-cost synthesis route for producing superhydrophobic surfaces on building materials is developed and their effectiveness and their durability on clay roof tiles are evaluated. Specifically, an organic-inorganic hybrid gel containing silica nanoparticles is produced. The nanoparticles create a densely packed coating on the roof tile surface in which air is trapped. This roughness produces a Cassie-Baxter regime, promoting superhydrophobicity. A surfactant, n-octylamine, was also added to the starting sol to catalyze the sol-gel process and to coarsen the pore structure of the gel network, preventing cracking. The application of ultrasound obviates the need to use volatile organic compounds in the synthesis, thereby making a 'green' product. It was also demonstrated that a co-condensation process effective between the organic and inorganic species is crucial to obtain durable and effective coatings. After an aging test, high hydrophobicity was maintained and water absorption was completely prevented for the roof tile samples under study. However, a transition from a Cassie-Baxter to a Wenzel state regime was observed as a consequence of the increase in the distance between the roughness pitches produced by the aging of the coating.

  18. Impact of height and shape of building roof on air quality in urban street canyons

    NASA Astrophysics Data System (ADS)

    Yassin, Mohamed F.

    2011-09-01

    A building's roof shape and roof height play an important role in determining pollutant concentrations from vehicle emissions and its complex flow patterns within urban street canyons. The impact of the roof shape and height on wind flow and dispersion of gaseous pollutants from vehicle exhaust within urban canyons were investigated numerically using a Computational Fluid Dynamics (CFD) model. Two-dimensional flow and dispersion of gaseous pollutants were analyzed using standard κ- ɛ turbulence model, which was numerically solved based on Reynolds Averaged Navier-Stokes (RANS) equations. The diffusion fields in the urban canyons were examined with three roof heights ( Z H/ H = 0.17, 0.33 and 0.5) and five roof shapes: (1) flat-shaped roof, (2) slanted-shaped roof, (3) downwind wedge-shaped roof, (4) upwind wedge-shaped roof, and (5) trapezoid-shaped roof. The numerical model was validated against the wind tunnels results in order to optimize the turbulence model. The numerical simulations agreed reasonably with the wind tunnel results. The results obtained indicated that the pollutant concentration increased as the roof height decreases. It also decreased with the slanted and trapezoid-shaped roofs but increased with the flat-shaped roof. The pollutant concentration distributions simulated in the present work, indicated that the variability of the roof shapes and roof heights of the buildings are important factors for estimating air quality within urban canyons.

  19. Experimental study on foam coverage on simulated longwall roof.

    PubMed

    Reed, W R; Zheng, Y; Klima, S; Shahan, M R; Beck, T W

    2017-01-01

    Testing was conducted to determine the ability of foam to maintain roof coverage in a simulated longwall mining environment. Approximately 27 percent of respirable coal mine dust can be attributed to longwall shield movement, and developing controls for this dust source has been difficult. The application of foam is a possible dust control method for this source. Laboratory testing of two foam agents was conducted to determine the ability of the foam to adhere to a simulated longwall face roof surface. Two different foam generation methods were used: compressed air and blower air. Using a new imaging technology, image processing and analysis utilizing ImageJ software produced quantifiable results of foam roof coverage. For compressed air foam in 3.3 m/s (650 fpm) ventilation, 98 percent of agent A was intact while 95 percent of agent B was intact on the roof at three minutes after application. At 30 minutes after application, 94 percent of agent A was intact while only 20 percent of agent B remained. For blower air in 3.3 m/s (650 fpm) ventilation, the results were dependent upon nozzle type. Three different nozzles were tested. At 30 min after application, 74 to 92 percent of foam agent A remained, while 3 to 50 percent of foam agent B remained. Compressed air foam seems to remain intact for longer durations and is easier to apply than blower air foam. However, more water drained from the foam when using compressed air foam, which demonstrates that blower air foam retains more water at the roof surface. Agent A seemed to be the better performer as far as roof application is concerned. This testing demonstrates that roof application of foam is feasible and is able to withstand a typical face ventilation velocity, establishing this technique's potential for longwall shield dust control.

  20. Experimental study on foam coverage on simulated longwall roof

    PubMed Central

    Reed, W.R.; Zheng, Y.; Klima, S.; Shahan, M.R.; Beck, T.W.

    2018-01-01

    Testing was conducted to determine the ability of foam to maintain roof coverage in a simulated longwall mining environment. Approximately 27 percent of respirable coal mine dust can be attributed to longwall shield movement, and developing controls for this dust source has been difficult. The application of foam is a possible dust control method for this source. Laboratory testing of two foam agents was conducted to determine the ability of the foam to adhere to a simulated longwall face roof surface. Two different foam generation methods were used: compressed air and blower air. Using a new imaging technology, image processing and analysis utilizing ImageJ software produced quantifiable results of foam roof coverage. For compressed air foam in 3.3 m/s (650 fpm) ventilation, 98 percent of agent A was intact while 95 percent of agent B was intact on the roof at three minutes after application. At 30 minutes after application, 94 percent of agent A was intact while only 20 percent of agent B remained. For blower air in 3.3 m/s (650 fpm) ventilation, the results were dependent upon nozzle type. Three different nozzles were tested. At 30 min after application, 74 to 92 percent of foam agent A remained, while 3 to 50 percent of foam agent B remained. Compressed air foam seems to remain intact for longer durations and is easier to apply than blower air foam. However, more water drained from the foam when using compressed air foam, which demonstrates that blower air foam retains more water at the roof surface. Agent A seemed to be the better performer as far as roof application is concerned. This testing demonstrates that roof application of foam is feasible and is able to withstand a typical face ventilation velocity, establishing this technique’s potential for longwall shield dust control. PMID:29563765

  1. Manipulating soil microbial communities in extensive green roof substrates.

    PubMed

    Molineux, Chloe J; Connop, Stuart P; Gange, Alan C

    2014-09-15

    There has been very little investigation into the soil microbial community on green roofs, yet this below ground habitat is vital for ecosystem functioning. Green roofs are often harsh environments that would greatly benefit from having a healthy microbial system, allowing efficient nutrient cycling and a degree of drought tolerance in dry summer months. To test if green roof microbial communities could be manipulated, we added mycorrhizal fungi and a microbial mixture ('compost tea') to green roof rootzones, composed mainly of crushed brick or crushed concrete. The study revealed that growing media type and depth play a vital role in the microbial ecology of green roofs. There are complex relationships between depth and type of substrate and the biomass of different microbial groups, with no clear pattern being observed. Following the addition of inoculants, bacterial groups tended to increase in biomass in shallower substrates, whereas fungal biomass change was dependent on depth and type of substrate. Increased fungal biomass was found in shallow plots containing more crushed concrete and deeper plots containing more crushed brick where compost tea (a live mixture of beneficial bacteria) was added, perhaps due to the presence of helper bacteria for arbuscular mycorrhizal fungi (AMF). Often there was not an additive affect of the microbial inoculations but instead an antagonistic interaction between the added AM fungi and the compost tea. This suggests that some species of microbes may not be compatible with others, as competition for limited resources occurs within the various substrates. The overall results suggest that microbial inoculations of green roof habitats are sustainable. They need only be done once for increased biomass to be found in subsequent years, indicating that this is a novel and viable method of enhancing roof community composition. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Getting a Clear Focus on Roof Replacement and Management.

    ERIC Educational Resources Information Center

    Patterson, Valerie B.

    2002-01-01

    Describes how a new generation of X-ray-like vision--the patented INFRARED2k--provides roof-condition reports that help extend roof life, conserve energy, and survey for mold-supporting environments, thereby improving indoor air quality. (EV)

  3. Thermoplastic Single-Ply Roof Relieves Water Damage and Inconvenience.

    ERIC Educational Resources Information Center

    Williams, Jennifer Lynn

    2002-01-01

    Assesses use of thermoplastic single-ply roofs by North Carolina's Mars Hill College to prevent leaks, reduce maintenance costs, and enhance the value of their older historic buildings. Administrators comment on the roof's installation efficiency and cleanliness. (GR)

  4. A pilot study to evaluate runoff quantity from green roofs.

    PubMed

    Lee, Ju Young; Lee, Min Jung; Han, Mooyoung

    2015-04-01

    The use of green roofs is gaining increased recognition in many countries as a solution that can be used to improve environmental quality and reduce runoff quantity. To achieve these goals, pilot-scale green roof assemblies have been constructed and operated in an urban setting. From a stormwater management perspective, green roofs are 42.8-60.8% effective in reducing runoff for 200 mm soil depth and 13.8-34.4% effective in reducing runoff for 150 mm soil depth. By using Spearman rank correlation analysis, high rainfall intensity was shown to have a negative relationship with delayed occurrence time, demonstrating that the soil media in green roofs do not efficiently retain rainwater. Increasing the number of antecedent dry days can help to improve water retention capacity and delay occurrence time. From the viewpoint of runoff water quality, green roofs are regarded as the best management practice by filtration and adsorption through growth media (soil). Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Radioactive cesium in dirt accumulations on the roof of buildings.

    PubMed

    Fujita, J; Mikasa, H; Fujii, N; Suzuki, Y; Nishiyama, K

    1992-12-01

    The concentrations of 137Cs and 134Cs in dirt deposits on the roofs of buildings are much higher than those in the surface of soil at ground level. Thus dirt on roofs concentrates radioactive cesium in fall-outs. The 137Cs concentration in dirt deposits on the roofs of older buildings is not consistently higher than that on the roofs of new ones, but the 137Cs/134Cs ratio is higher in deposits on older buildings constructed before the first half of the 1970s, and decreases exponentially with decrease in age of the buildings gradually reaching 1.9 +/- 0.2, the value in the air-borne dust at the time of the Chernobyl accident. From this relationship, the contribution of Chernobyl radioactivity to accumulated 137Cs was calculated as 32% on buildings constructed in 1962. The radioactive cesium concentrations in dirt deposits in gutters of private houses and on the roofs of university buildings in Japan were also determined.

  6. Sustainable Retrofit of Residential Roofs Using Metal Roofing Panels, Thin-Film Photovoltaic Laminates, and PCM Heat Sink Technology

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kosny, Jan; Miller, William A; Childs, Phillip W

    2011-01-01

    During September-October 2009, research teams representing Metal Construction Association (the largest North American trade association representing metal building manufacturers, builders, and material suppliers), CertainTeed (one of the largest U.S. manufacturers of thermal insulation and building envelope materials), Unisolar (largest U.S. producer of amorphous silicone photo-voltaic (PV) laminates), Phase Change Energy (manufacturer of bio-based PCM), and Oak Ridge National Laboratory (ORNL) installed three experimental attics utilizing different roof retrofit strategies in the ORNL campus. The main goal of this project was experimental evaluation of a newly-developed sustainable re-roofing technology utilizing amorphous silicone PV laminates integrated with metal roof and PCM heatmore » sink. The experimental attic with PV laminate was expected to work during the winter time as a passive solar collector with PCM storing solar heat, absorbed during the day, and increasing overall attic air temperature during the night.« less

  7. Summer Thermal Performance of Ventilated Roofs with Tiled Coverings

    NASA Astrophysics Data System (ADS)

    Bortoloni, M.; Bottarelli, M.; Piva, S.

    2017-01-01

    The thermal performance of a ventilated pitched roof with tiled coverings is analysed and compared with unventilated roofs. The analysis is carried out by means of a finite element numerical code, by solving both the fluid and thermal problems in steady-state. A whole one-floor building with a pitched roof is schematized as a 2D computational domain including the air-permeability of tiled covering. Realistic data sets for wind, temperature and solar radiation are used to simulate summer conditions at different times of the day. The results demonstrate that the batten space in pitched roofs is an effective solution for reducing the solar heat gain in summer and thus for achieving better indoor comfort conditions. The efficiency of the ventilation is strictly linked to the external wind conditions and to buoyancy forces occurring due to the heating of the tiles.

  8. Plant species richness enhances nitrogen retention in green roof plots.

    PubMed

    Johnson, Catherine; Schweinhart, Shelbye; Buffam, Ishi

    2016-10-01

    Vegetated (green) roofs have become common in many cities and are projected to continue to increase in coverage, but little is known about the ecological properties of these engineered ecosystems. In this study, we tested the biodiversity-ecosystem function hypothesis using commercially available green roof trays as replicated plots with varying levels of plant species richness (0, 1, 3, or 6 common green roof species per plot, using plants with different functional characteristics). We estimated accumulated plant biomass near the peak of the first full growing season (July 2013) and measured runoff volume after nearly every rain event from September 2012 to September 2013 (33 events) and runoff fluxes of inorganic nutrients ammonium, nitrate, and phosphate from a subset of 10 events. We found that (1) total plant biomass increased with increasing species richness, (2) green roof plots were effective at reducing storm runoff, with vegetation increasing water retention more than soil-like substrate alone, but there was no significant effect of plant species identity or richness on runoff volume, (3) green roof substrate was a significant source of phosphate, regardless of presence/absence of plants, and (4) dissolved inorganic nitrogen (DIN = nitrate + ammonium) runoff fluxes were different among plant species and decreased significantly with increasing plant species richness. The variation in N retention was positively related to variation in plant biomass. Notably, the increased biomass and N retention with species richness in this engineered ecosystem are similar to patterns observed in published studies from grasslands and other well-studied ecosystems. We suggest that more diverse plantings on vegetated roofs may enhance the retention capacity for reactive nitrogen. This is of importance for the sustained health of vegetated roof ecosystems, which over time often experience nitrogen limitation, and is also relevant for water quality in receiving waters

  9. Evaluating convex roof entanglement measures.

    PubMed

    Tóth, Géza; Moroder, Tobias; Gühne, Otfried

    2015-04-24

    We show a powerful method to compute entanglement measures based on convex roof constructions. In particular, our method is applicable to measures that, for pure states, can be written as low order polynomials of operator expectation values. We show how to compute the linear entropy of entanglement, the linear entanglement of assistance, and a bound on the dimension of the entanglement for bipartite systems. We discuss how to obtain the convex roof of the three-tangle for three-qubit states. We also show how to calculate the linear entropy of entanglement and the quantum Fisher information based on partial information or device independent information. We demonstrate the usefulness of our method by concrete examples.

  10. The effect of roof strength on reducing occupant injury in rollovers.

    PubMed

    Herbst, Brian; Forrest, Steve; Orton, Tia; Meyer, Steven E; Sances, Anthony; Kumaresan, Srirangam

    2005-01-01

    Roof crush occurs and potentially contributes to serious or fatal occupant injury in 26% of rollovers. It is likely that glazing retention is related to the degree of roof crush experienced in rollover accidents. Occupant ejection (including partial ejection) is the leading cause of death and injury in rollover accidents. In fatal passenger car accidents involving ejection, 34% were ejected through the side windows. Side window glass retention during a rollover is likely to significantly reduce occupant ejections. The inverted drop test methodology is a test procedure to evaluate the structural integrity of roofs under loadings similar to those seen in real world rollovers. Recent testing on many different vehicle types indicates that damage consistent with field rollover accidents can be achieved through inverted drop testing at very small drop heights. Drop test comparisons were performed on 16 pairs of vehicles representing a large spectrum of vehicle types. Each vehicle pair includes a production vehicle and a vehicle with a reinforced roof structure dropped under the same test conditions. This paper offers several examples of post-production reinforcements to roof structures that significantly increase the crush resistance of the roof as measured by inverted drop tests. These modifications were implemented with minimal impact on vehicle styling, interior space and visual clearances. The results of these modifications indicate that roof crush can be mitigated by nearly an order of magnitude, as roof crush was reduced by 44-91% with only a 1-2.3% increase in vehicle weight. Additionally, this paper analyzes the glazing breakage patterns in the moveable tempered side windows on the side adjacent to the vehicle impact point in the inverted drop tests. A comparison is made between the production vehicles and the reinforced vehicles in order to determine if the amount roof crush is related to glazing integrity in the side windows. Lastly, two drop test pairs

  11. Roof strength and injury risk in rollover crashes of passenger cars.

    PubMed

    Brumbelow, Matthew L; Teoh, Eric R

    2009-12-01

    A 2009 study by the Insurance Institute for Highway Safety found that midsize SUVs with stronger roofs, as measured in quasi-static tests, had lower risk of ejection and lower risk of injury for nonejected drivers. The objective of the present study was to determine whether a similar association exists for other vehicle groups. Twelve small passenger cars were evaluated according to Federal Motor Vehicle Safety Standard 216 test conditions. Crash databases in 14 states provided more than 20,000 single-vehicle rollover crashes involving these vehicles. Logistic regression analyses were used to evaluate the effect of roof strength on the rate of driver injury while assessing and controlling for the effects of driver age, vehicle stability, state, and other factors where necessary. Small cars with stronger roofs had lower overall rates of serious injury, lower rates of ejection, and lower rates of injury for nonejected drivers. Although the effect on ejection was somewhat smaller for cars than for SUVs, the overall pattern of injury results was consistent. For roof strength-to-weight ratio measured within 5 in. (SWR(5)), a one-unit increase (e.g., from 2.0 to 3.0) was associated with a 22 percent reduction in risk of incapacitating or fatal driver injury in single-vehicle rollovers. This compares with a 24 percent reduction estimated for a similar change in roof strength among midsize SUVs. The association between vehicle roof strength and occupant injury risk in rollover crashes appears robust across different vehicle groups and across roof SWR(5) values, varying from just more than 1.5 to just less than 4.0. If roofs were to increase in strength by one SWR(5), a 20-25 percent reduction in risk of serious injury in rollovers would be expected. Still, even if all vehicle roofs were as strong as the strongest roof measured, many rollover injuries still would occur, indicating the need for additional research and countermeasures.

  12. Separating Drought Effects from Roof Artifacts on Ecosystem Processes in a Grassland Drought Experiment

    PubMed Central

    Vogel, Anja; Fester, Thomas; Eisenhauer, Nico; Scherer-Lorenzen, Michael; Schmid, Bernhard; Weisser, Wolfgang W.; Weigelt, Alexandra

    2013-01-01

    1 Given the predictions of increased drought probabilities under various climate change scenarios, there have been numerous experimental field studies simulating drought using transparent roofs in different ecosystems and regions. Such roofs may, however, have unknown side effects, called artifacts, on the measured variables potentially confounding the experimental results. A roofed control allows the quantification of potential artifacts, which is lacking in most experiments. 2 We conducted a drought experiment in experimental grasslands to study artifacts of transparent roofs and the resulting effects of artifacts on ecosystems relative to drought on three response variables (aboveground biomass, litter decomposition and plant metabolite profiles). We established three drought treatments, using (1) transparent roofs to exclude rainfall, (2) an unroofed control treatment receiving natural rainfall and (3) a roofed control, nested in the drought treatment but with rain water reapplied according to ambient conditions. 3 Roofs had a slight impact on air (+0.14°C during night) and soil temperatures (−0.45°C on warm days, +0.25°C on cold nights), while photosynthetically active radiation was decreased significantly (−16%). Aboveground plant community biomass was reduced in the drought treatment (−41%), but there was no significant difference between the roofed and unroofed control, i.e., there were no measurable roof artifact effects. 4 Compared to the unroofed control, litter decomposition was decreased significantly both in the drought treatment (−26%) and in the roofed control treatment (−18%), suggesting artifact effects of the transparent roofs. Moreover, aboveground metabolite profiles in the model plant species Medicago x varia were different from the unroofed control in both the drought and roofed control treatments, and roof artifact effects were of comparable magnitude as drought effects. 5 Our results stress the need for roofed control

  13. Impact of green roofs on stormwater quality in a South Australian urban environment.

    PubMed

    Razzaghmanesh, M; Beecham, S; Kazemi, F

    2014-02-01

    Green roofs are an increasingly important component of water sensitive urban design systems and can potentially improve the quality of urban runoff. However, there is evidence that they can occasionally act as a source rather than a sink for pollutants. In this study, the water quality of the outflow from both intensive and extensive green roof systems were studied in the city of Adelaide, South Australia over a period of nine months. The aim was to examine the effects of different green roof configurations on stormwater quality and to compare this with runoff from aluminium and asphalt roofs as control surfaces. The contaminant concentrations in runoff from both intensive and extensive green roofs generally decreased during the study period. A comparison between the two types of green roof showed that except for some events for EC, TDS and chloride, the values of the parameters such as pH, turbidity, nitrate, phosphate and potassium in intensive green roof outflows were higher than in the outflows from the extensive green roofs. These concentrations were compared to local, state, national and international water quality guidelines in order to investigate the potential for outflow runoff from green roofs to be reused for potable and non-potable purposes. The study found that green roof outflow can provide an alternative water source for non-potable purposes such as urban landscape irrigation and toilet flushing. © 2013.

  14. Feasibility of determining flat roof heat losses using aerial thermography

    NASA Technical Reports Server (NTRS)

    Bowman, R. L.; Jack, J. R.

    1979-01-01

    The utility of aerial thermography for determining rooftop heat losses was investigated experimentally using several completely instrumented test roofs with known thermal resistances. Actual rooftop heat losses were obtained both from in-situ instrumentation and aerial thermography obtained from overflights at an altitude of 305 m. In general, the remotely determined roof surface temperatures agreed very well with those obtained from ground measurements. The roof heat losses calculated using the remotely determined roof temperature agreed to within 17% of those calculated from 1/R delta T using ground measurements. However, this agreement may be fortuitous since the convective component of the heat loss is sensitive to small changes in roof temperature and to the average heat transfer coefficient used, whereas the radiative component is less sensitive. This, at this time, it is felt that an acceptable quantitative determination of roof heat losses using aerial thermography is only feasible when the convective term is accurately known or minimized. The sensitivity of the heat loss determination to environmental conditions was also evaluated. The analysis showed that the most reliable quantitative heat loss determinations can probably be obtained from aerial thermography taken under conditions of total cloud cover with low wind speeds and at low ambient temperatures.

  15. Roofing research and standards development: Fourth volume. ASTM special technical publication 1349

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wallace, T.J.; Rossiter, W.J. Jr.

    1999-07-01

    As the roofing industry has stabilized, a broad variety of roof systems have found general acceptance by the building owners, architects, engineers, contractors, and others who select and install roofs. These roof systems include those based on conventional built-up membranes using glass and synthetic reinforcements, synthetic polymeric membranes using elastomers and thermoplastics, polymer-modified membranes, and sprayed polyurethane foam. ASTM Committee D8 on Roofing, Waterproofing, and Bituminous Materials has contributed significantly in many important ways to the roofing community's stabilization including issuing standard specifications to assist consumers in the selection and use of these systems. This is not surprising, as itmore » has always been among the purpose of D8 to provide standards to assist in the selection and use of low-sloped and steep roofing. The Committee's scope includes development of standards associated with application, inspection, maintenance, and analyses. Some of the issues facing the roofing community today--for example, enhanced system durability, better methods of material characterization, environmental impact, recycling of materials and systems, industry conversation to the S.I. system metric--readily fall within D8's scope. The availability of sound standard can contribute to the resolution of many of these issues.« less

  16. A Study of the Energy-Saving Potential of Metal Roofs Incorporating Dynamic Insulation Systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Biswas, Kaushik; Miller, William A; Kriner, Scott

    2013-01-01

    This article presents various metal roof configurations that were tested at Oak Ridge National Laboratory in Tennessee, U.S. between 2009 and 2013, and describes their potential for reducing the attic-generated space-conditioning loads. These roofs contained different combinations of phase-change material, rigid insulation, low emittance surface, and above-sheathing ventilation with standing-seam metal panels on top. These roofs were designed to be installed on existing roofs decks, or on top of asphalt shingles for retrofit construction. All the tested roofs showed the potential for substantial energy savings compared to an asphalt shingle roof, which was used as a control for comparison. Themore » roofs were constructed on a series of adjacent attics separated at the gables using thick foam insulation. The attics were built on top of a conditioned room. All attics were vented at the soffit and ridge. The test roofs and attics were instrumented with an array of thermocouples. Heat flux transducers were installed in the roof deck and attic floor (ceiling) to measure the heat flows through the roof and between the attic and conditioned space below. Temperature and heat flux data were collected during the heating, cooling and swing seasons over a three-year period. Data from previous years of testing have been published. Here, data from the latest roof configurations being tested in year three of the project are presented. All test roofs were highly effective in reducing the heat flows through the roof and ceiling, and in reducing the diurnal attic-temperature fluctuations.« less

  17. Performance of dryland and wetland plant species on extensive green roofs.

    PubMed

    MacIvor, J Scott; Ranalli, Melissa A; Lundholm, Jeremy T

    2011-04-01

    Green roofs are constructed ecosystems where plants perform valuable services, ameliorating the urban environment through roof temperature reductions and stormwater interception. Plant species differ in functional characteristics that alter ecosystem properties. Plant performance research on extensive green roofs has so far indicated that species adapted to dry conditions perform optimally. However, in moist, humid climates, species typical of wetter soils might have advantages over dryland species. In this study, survival, growth and the performance of thermal and stormwater capture functions of three pairs of dryland and wetland plant species were quantified using an extensive modular green roof system. Seedlings of all six species were germinated in a greenhouse and planted into green roof modules with 6 cm of growing medium. There were 34 treatments consisting of each species in monoculture and all combinations of wet- and dryland species in a randomized block design. Performance measures were survival, vegetation cover and roof surface temperature recorded for each module over two growing seasons, water loss (an estimate of evapotranspiration) in 2007, and albedo and water capture in 2008. Over two seasons, dryland plants performed better than wetland plants, and increasing the number of dryland species in mixtures tended to improve functioning, although there was no clear effect of species or habitat group diversity. All species had survival rates >75 % after the first winter; however, dryland species had much greater cover, an important indicator of green roof performance. Sibbaldiopsis tridentata was the top performing species in monoculture, and was included in the best treatments. Although dryland species outperformed wetland species, planting extensive green roofs with both groups decreased performance only slightly, while increasing diversity and possibly habitat value. This study provides further evidence that plant composition and diversity can

  18. Performance of dryland and wetland plant species on extensive green roofs

    PubMed Central

    MacIvor, J. Scott; Ranalli, Melissa A.; Lundholm, Jeremy T.

    2011-01-01

    Background and Aims Green roofs are constructed ecosystems where plants perform valuable services, ameliorating the urban environment through roof temperature reductions and stormwater interception. Plant species differ in functional characteristics that alter ecosystem properties. Plant performance research on extensive green roofs has so far indicated that species adapted to dry conditions perform optimally. However, in moist, humid climates, species typical of wetter soils might have advantages over dryland species. In this study, survival, growth and the performance of thermal and stormwater capture functions of three pairs of dryland and wetland plant species were quantified using an extensive modular green roof system. Methods Seedlings of all six species were germinated in a greenhouse and planted into green roof modules with 6 cm of growing medium. There were 34 treatments consisting of each species in monoculture and all combinations of wet- and dryland species in a randomized block design. Performance measures were survival, vegetation cover and roof surface temperature recorded for each module over two growing seasons, water loss (an estimate of evapotranspiration) in 2007, and albedo and water capture in 2008. Key Results Over two seasons, dryland plants performed better than wetland plants, and increasing the number of dryland species in mixtures tended to improve functioning, although there was no clear effect of species or habitat group diversity. All species had survival rates >75 % after the first winter; however, dryland species had much greater cover, an important indicator of green roof performance. Sibbaldiopsis tridentata was the top performing species in monoculture, and was included in the best treatments. Conclusions Although dryland species outperformed wetland species, planting extensive green roofs with both groups decreased performance only slightly, while increasing diversity and possibly habitat value. This study provides further

  19. Cladonia lichens on extensive green roofs: evapotranspiration, substrate temperature, and albedo.

    PubMed

    Heim, Amy; Lundholm, Jeremy

    2013-01-01

    Green roofs are constructed ecosystems that provide ecosystem services in urban environments. Shallow substrate green roofs subject the vegetation layer to desiccation and other environmental extremes, so researchers have evaluated a variety of stress-tolerant vegetation types for green roof applications. Lichens can be found in most terrestrial habitats.  They are able to survive extremely harsh conditions, including frequent cycles of desiccation and rehydration, nutrient-poor soil, fluctuating temperatures, and high UV intensities. Extensive green roofs (substrate depth <20cm) exhibit these harsh conditions, making lichens possible candidates for incorporation into the vegetation layer on extensive green roofs.  In a modular green roof system, we tested the effect of Cladonia lichens on substrate temperature, water loss, and albedo compared to a substrate-only control. Overall, the Cladonia modules had significantly cooler substrate temperatures during the summer and significantly warmer temperatures during the fall.  Additionally, the Cladonia modules lost significantly less water than the substrate-only control. This implies that they may be able to benefit neighboring vascular plant species by reducing water loss and maintaining favorable substrate temperatures.

  20. A two-stage storage routing model for green roof runoff detention.

    PubMed

    Vesuviano, Gianni; Sonnenwald, Fred; Stovin, Virginia

    2014-01-01

    Green roofs have been adopted in urban drainage systems to control the total quantity and volumetric flow rate of runoff. Modern green roof designs are multi-layered, their main components being vegetation, substrate and, in almost all cases, a separate drainage layer. Most current hydrological models of green roofs combine the modelling of the separate layers into a single process; these models have limited predictive capability for roofs not sharing the same design. An adaptable, generic, two-stage model for a system consisting of a granular substrate over a hard plastic 'egg box'-style drainage layer and fibrous protection mat is presented. The substrate and drainage layer/protection mat are modelled separately by previously verified sub-models. Controlled storm events are applied to a green roof system in a rainfall simulator. The time-series modelled runoff is compared to the monitored runoff for each storm event. The modelled runoff profiles are accurate (mean Rt(2) = 0.971), but further characterization of the substrate component is required for the model to be generically applicable to other roof configurations with different substrate.

  1. Retention performance of green roofs in representative climates worldwide

    NASA Astrophysics Data System (ADS)

    Viola, F.; Hellies, M.; Deidda, R.

    2017-10-01

    The ongoing process of global urbanization contributes to an increase in stormwater runoff from impervious surfaces, threatening also water quality. Green roofs have been proved to be innovative stormwater management measures to partially restore natural states, enhancing interception, infiltration and evapotranspiration fluxes. The amount of water that is retained within green roofs depends not only on their depth, but also on the climate, which drives the stochastic soil moisture dynamic. In this context, a simple tool for assessing performance of green roofs worldwide in terms of retained water is still missing and highly desirable for practical assessments. The aim of this work is to explore retention performance of green roofs as a function of their depth and in different climate regimes. Two soil depths are investigated, one representing the intensive configuration and another representing the extensive one. The role of the climate in driving water retention has been represented by rainfall and potential evapotranspiration dynamics. A simple conceptual weather generator has been implemented and used for stochastic simulation of daily rainfall and potential evapotranspiration. Stochastic forcing is used as an input of a simple conceptual hydrological model for estimating long-term water partitioning between rainfall, runoff and actual evapotranspiration. Coupling the stochastic weather generator with the conceptual hydrological model, we assessed the amount of rainfall diverted into evapotranspiration for different combinations of annual rainfall and potential evapotranspiration in five representative climatic regimes. Results quantified the capabilities of green roofs in retaining rainfall and consequently in reducing discharges into sewer systems at an annual time scale. The role of substrate depth has been recognized to be crucial in determining green roofs retention performance, which in general increase from extensive to intensive settings. Looking at the

  2. Extensive Green Roof Research Program at Colorado State University

    EPA Science Inventory

    In the high elevation, semi-arid climate of Colorado, green roofs have not been scientifically tested. This research examined alternative plant species, media blends, and plant interactions on an existing modular extensive green roof in Denver, Colorado. Six plant species were ev...

  3. Snow loads on roofs in areas of heavy snowfall

    Treesearch

    Robert D. Doty; Glenn H. Deitschman

    1966-01-01

    This study tested the feasibility of estimating snow loads on roofs from measurements of depth and water content of snow on nearby ground. The water content, and therefore the weight, of snow on the ground proved comparable to that of snow on roofs.

  4. Metal roof corrosion related to volcanic ash deposition

    NASA Astrophysics Data System (ADS)

    Oze, C.; Cole, J. W.; Scott, A.; Wilson, T.; Wilson, G.; Gaw, S.; Hampton, S.; Doyle, C.; Li, Z.

    2013-12-01

    Volcanoes produce a wide range of hazards capable of leading to increased rates of corrosion to the built environment. Specifically, widely distributed volcanic ash derived from explosive volcanic eruptions creates both short- and long-term hazards to infrastructure including increased corrosion to exposed building materials such as metal roofing. Corrosion has been attributed to volcanic ash in several studies, but these studies are observational and are beset by limitations such as not accounting for pre-existing corrosion damage and/or other factors that may have also directly contributed to corrosion. Here, we evaluate the corrosive effects of volcanic ash, specifically focusing on the role of ash leachates, on a variety of metal roofing materials via weathering chamber experiments. Weathering chamber tests were carried out for up to 30 days using a synthetic ash dosed with an acidic solution to produce a leachate comparable to a real volcanic ash. Visual, chemical and surface analyses did not definitively identify significant corrosion in any of the test roofing metal samples. These experiments attempted to provide quantitative information with regards to the rates of corrosion of different types of metal roof materials. However, they demonstrate that no significant corrosion was macroscopically or microscopically present on any of the roofing surfaces despite the presence of corrosive salts after a duration of thirty days. These results suggest ash leachate-related corrosion is not a major or immediate concern in the short-term (< 1 month).

  5. Habitat connectivity shapes urban arthropod communities: the key role of green roofs.

    PubMed

    Braaker, S; Ghazoul, J; Obrist, M K; Moretti, M

    2014-04-01

    The installation of green roofs, defined here as rooftops with a shallow soil cover and extensive vegetation, has been proposed as a possible measure to mitigate the loss of green space caused by the steady growth of cities. However, the effectiveness of green roofs in supporting arthropod communities, and the extent to which they facilitate connectivity of these communities within the urban environment is currently largely unknown. We investigated the variation of species community composition (beta diversity) of four arthropod groups with contrasting mobility (Carabidae, Araneae, Curculionidae, and Apidae) on 40 green roofs and 40 extensively managed green sites on the ground in the city of Zurich, Switzerland. With redundancy analysis and variation partitioning, we (1) disentangled the relative importance of local environmental conditions, the surrounding land cover composition, and habitat connectivity on species community composition, (2) searched for specific spatial scales of habitat connectivity for the different arthropod groups, and (3) discussed the ecological and functional value of green roofs in cities. Our study revealed that on green roofs community composition of high-mobility arthropod groups (bees and weevils) were mainly shaped by habitat connectivity, while low-mobility arthropod groups (carabids and spiders) were more influenced by local environmental conditions. A similar but less pronounced pattern was found for ground communities. The high importance of habitat connectivity in shaping high-mobility species community composition indicates that these green roof communities are substantially connected by the frequent exchange of individuals among surrounding green roofs. On the other hand, low-mobility species communities on green roofs are more likely connected to ground sites than to other green roofs. The integration of green roofs in urban spatial planning strategies has great potential to enable higher connectivity among green spaces, so

  6. Stretching morphogenesis of the roof plate and formation of the central canal.

    PubMed

    Kondrychyn, Igor; Teh, Cathleen; Sin, Melvin; Korzh, Vladimir

    2013-01-01

    Neurulation is driven by apical constriction of actomyosin cytoskeleton resulting in conversion of the primitive lumen into the central canal in a mechanism driven by F-actin constriction, cell overcrowding and buildup of axonal tracts. The roof plate of the neural tube acts as the dorsal morphogenetic center and boundary preventing midline crossing by neural cells and axons. The roof plate zebrafish transgenics expressing cytosolic GFP were used to study and describe development of this structure in vivo for a first time ever. The conversion of the primitive lumen into the central canal causes significant morphogenetic changes of neuroepithelial cells in the dorsal neural tube. We demonstrated that the roof plate cells stretch along the D-V axis in parallel with conversion of the primitive lumen into central canal and its ventral displacement. Importantly, the stretching of the roof plate is well-coordinated along the whole spinal cord and the roof plate cells extend 3× in length to cover 2/3 of the neural tube diameter. This process involves the visco-elastic extension of the roof place cytoskeleton and depends on activity of Zic6 and the Rho-associated kinase (Rock). In contrast, stretching of the floor plate is much less extensive. The extension of the roof plate requires its attachment to the apical complex of proteins at the surface of the central canal, which depends on activity of Zic6 and Rock. The D-V extension of the roof plate may change a range and distribution of morphogens it produces. The resistance of the roof plate cytoskeleton attenuates ventral displacement of the central canal in illustration of the novel mechanical role of the roof plate during development of the body axis.

  7. Stretching Morphogenesis of the Roof Plate and Formation of the Central Canal

    PubMed Central

    Kondrychyn, Igor; Teh, Cathleen; Sin, Melvin; Korzh, Vladimir

    2013-01-01

    Background Neurulation is driven by apical constriction of actomyosin cytoskeleton resulting in conversion of the primitive lumen into the central canal in a mechanism driven by F-actin constriction, cell overcrowding and buildup of axonal tracts. The roof plate of the neural tube acts as the dorsal morphogenetic center and boundary preventing midline crossing by neural cells and axons. Methodology/Principal Findings The roof plate zebrafish transgenics expressing cytosolic GFP were used to study and describe development of this structure in vivo for a first time ever. The conversion of the primitive lumen into the central canal causes significant morphogenetic changes of neuroepithelial cells in the dorsal neural tube. We demonstrated that the roof plate cells stretch along the D–V axis in parallel with conversion of the primitive lumen into central canal and its ventral displacement. Importantly, the stretching of the roof plate is well-coordinated along the whole spinal cord and the roof plate cells extend 3× in length to cover 2/3 of the neural tube diameter. This process involves the visco-elastic extension of the roof place cytoskeleton and depends on activity of Zic6 and the Rho-associated kinase (Rock). In contrast, stretching of the floor plate is much less extensive. Conclusions/Significance The extension of the roof plate requires its attachment to the apical complex of proteins at the surface of the central canal, which depends on activity of Zic6 and Rock. The D–V extension of the roof plate may change a range and distribution of morphogens it produces. The resistance of the roof plate cytoskeleton attenuates ventral displacement of the central canal in illustration of the novel mechanical role of the roof plate during development of the body axis. PMID:23409159

  8. Thermal and Energy Performance of Conditioned Building Due To Insulated Sloped Roof

    NASA Astrophysics Data System (ADS)

    Irwan, Suhandi Syiful; Ahmed, Azni Zain; Zakaria, Nor Zaini; Ibrahim, Norhati

    2010-07-01

    For low-rise buildings in equatorial region, the roof is exposed to solar radiation longer than other parts of the envelope. Roofs are to be designed to reject heat and moderate the thermal impact. These are determined by the design and construction of the roofing system. The pitch of roof and the properties of construction affect the heat gain into the attic and subsequently the indoor temperature of the living spaces underneath. This finally influences the thermal comfort conditions of naturally ventilated buildings and cooling load of conditioned buildings. This study investigated the effect of insulated sloping roof on thermal energy performance of the building. A whole-building thermal energy computer simulation tool, Integrated Environmental Solution (IES), was used for the modelling and analyses. A building model with dimension of 4.0 m × 4.0 m × 3.0 m was designed with insulated roof and conventional construction for other parts of the envelope. A 75 mm conductive insulation material with thermal conductivity (k-value) of 0.034 Wm-1K-1 was installed underneath the roof tiles. The building was modelled with roof pitch angles of 0° , 15°, 30°, 45°, 60° and simulated for the month of August in Malaysian climate conditions. The profile for attic temperature, indoor temperature and cooling load were downloaded and evaluated. The optimum roof pitch angle for best thermal performance and energy saving was identified. The results show the pitch angle of 0° is able to mitigate the thermal impact to provide the best thermal condition with optimum energy savings. The maximum temperature difference between insulated and non-insulted roof for attic (AtticA-B) and indoor condition (IndoorA-B) is +7.8 °C and 0.4 °C respectively with an average energy monthly savings of 3.9 %.

  9. Digging the New York City Skyline: Soil Fungal Communities in Green Roofs and City Parks

    PubMed Central

    McGuire, Krista L.; Payne, Sara G.; Palmer, Matthew I.; Gillikin, Caitlyn M.; Keefe, Dominique; Kim, Su Jin; Gedallovich, Seren M.; Discenza, Julia; Rangamannar, Ramya; Koshner, Jennifer A.; Massmann, Audrey L.; Orazi, Giulia; Essene, Adam; Leff, Jonathan W.; Fierer, Noah

    2013-01-01

    In urban environments, green roofs provide a number of benefits, including decreased urban heat island effects and reduced energy costs for buildings. However, little research has been done on the non-plant biota associated with green roofs, which likely affect their functionality. For the current study, we evaluated whether or not green roofs planted with two native plant communities in New York City functioned as habitats for soil fungal communities, and compared fungal communities in green roof growing media to soil microbial composition in five city parks, including Central Park and the High Line. Ten replicate roofs were sampled one year after planting; three of these roofs were more intensively sampled and compared to nearby city parks. Using Illumina sequencing of the fungal ITS region we found that green roofs supported a diverse fungal community, with numerous taxa belonging to fungal groups capable of surviving in disturbed and polluted habitats. Across roofs, there was significant biogeographical clustering of fungal communities, indicating that community assembly of roof microbes across the greater New York City area is locally variable. Green roof fungal communities were compositionally distinct from city parks and only 54% of the green roof taxa were also found in the park soils. Phospholipid fatty acid analysis revealed that park soils had greater microbial biomass and higher bacterial to fungal ratios than green roof substrates. City park soils were also more enriched with heavy metals, had lower pH, and lower quantities of total bases (Ca, K, and Mg) compared to green roof substrates. While fungal communities were compositionally distinct across green roofs, they did not differentiate by plant community. Together, these results suggest that fungi living in the growing medium of green roofs may be an underestimated component of these biotic systems functioning to support some of the valued ecological services of green roofs. PMID:23469260

  10. Digging the New York City Skyline: soil fungal communities in green roofs and city parks.

    PubMed

    McGuire, Krista L; Payne, Sara G; Palmer, Matthew I; Gillikin, Caitlyn M; Keefe, Dominique; Kim, Su Jin; Gedallovich, Seren M; Discenza, Julia; Rangamannar, Ramya; Koshner, Jennifer A; Massmann, Audrey L; Orazi, Giulia; Essene, Adam; Leff, Jonathan W; Fierer, Noah

    2013-01-01

    In urban environments, green roofs provide a number of benefits, including decreased urban heat island effects and reduced energy costs for buildings. However, little research has been done on the non-plant biota associated with green roofs, which likely affect their functionality. For the current study, we evaluated whether or not green roofs planted with two native plant communities in New York City functioned as habitats for soil fungal communities, and compared fungal communities in green roof growing media to soil microbial composition in five city parks, including Central Park and the High Line. Ten replicate roofs were sampled one year after planting; three of these roofs were more intensively sampled and compared to nearby city parks. Using Illumina sequencing of the fungal ITS region we found that green roofs supported a diverse fungal community, with numerous taxa belonging to fungal groups capable of surviving in disturbed and polluted habitats. Across roofs, there was significant biogeographical clustering of fungal communities, indicating that community assembly of roof microbes across the greater New York City area is locally variable. Green roof fungal communities were compositionally distinct from city parks and only 54% of the green roof taxa were also found in the park soils. Phospholipid fatty acid analysis revealed that park soils had greater microbial biomass and higher bacterial to fungal ratios than green roof substrates. City park soils were also more enriched with heavy metals, had lower pH, and lower quantities of total bases (Ca, K, and Mg) compared to green roof substrates. While fungal communities were compositionally distinct across green roofs, they did not differentiate by plant community. Together, these results suggest that fungi living in the growing medium of green roofs may be an underestimated component of these biotic systems functioning to support some of the valued ecological services of green roofs.

  11. Green roofs'retention performances in different climates

    NASA Astrophysics Data System (ADS)

    Viola, Francesco; Hellies, Matteo; Deidda, Roberto

    2017-04-01

    The ongoing process of global urbanization contributes to increasing stormwater runoff from impervious surfaces, threatening also water quality. Green roofs have been proved to be an innovative stormwater management tool to partially restore natural state, enhancing interception, infiltration and evapotranspiration fluxes. The amount of water that is retained within green roofs depends mainly on both soil properties and climate. The evaluation of the retained water is not trivial since it depends on the stochastic soil moisture dynamics. The aim of this work is to explore performances of green roofs, in terms of water retention, as a function of their depth considering different climate regimes. The role of climate in driving water retention has been mainly represented by rainfall and potential evapotranspiration dynamics, which are simulated by a simple conceptual weather generator at daily time scale. The model is able to describe seasonal (in-phase and counter-phase) and stationary behaviors of climatic forcings. Model parameters have been estimated on more than 20,000 historical time series retrieved worldwide. Exemplifying cases are discussed for five different climate scenarios, changing the amplitude and/or the phase of daily mean rainfall and evapotranspiration forcings. The first scenario represents stationary climates, in two other cases the daily mean rainfall or the potential evapotranspiration evolve sinusoidally. In the latter two cases, we simulated the in-phase or in counter-phase conditions. Stochastic forcings have been then used as an input to a simple conceptual hydrological model which simulate soil moisture dynamics, evapotranspiration fluxes, runoff and leakage from soil pack at daily time scale. For several combinations of annual rainfall and potential evapotranspiration, the analysis allowed assessing green roofs' retaining capabilities, at annual time scale. Provided abacus allows a first approximation of possible hydrological benefits

  12. Energy analysis of cool, medium, and dark roofs on residential buildings in the U.S

    NASA Astrophysics Data System (ADS)

    Dunbar, Michael A.

    This study reports an energy analysis of cool, medium, and dark roofs on residential buildings in the U.S. Three analyses were undertaken in this study: energy consumption, economic analysis, and an environmental analysis. The energy consumption reports the electricity and natural gas consumption of the simulations. The economic analysis uses tools such as simple payback period (SPP) and net present value (NPV) to determine the profitability of the cool roof and the medium roof. The variable change for each simulation model was the roof color. The default color was a dark roof and the results were focused on the changes produced by the cool roof and the medium roof. The environmental analysis uses CO2 emissions to assess the environmental impact of the cool roof and the medium roof. The analysis uses the U.S. Department of Energy (DOE) EnergyPlus software to produce simulations of a typical, two-story residential home in the U.S. The building details of the typical, two-story U.S. residential home and the International Energy Conservation Code (IECC) building code standards used are discussed in this study. This study indicates that, when material and labor costs are. assessed, the cool roof and the medium roof do not yield a SPP less than 10 years. Furthermore, the NPV results assess that neither the cool roof nor the medium roof are a profitable investment in any climate zone in the U.S. The environmental analysis demonstrates that both the cool roof and the medium roof have a positive impact in warmer climates by reducing the CO2 emissions as much as 264 kg and 129 kg, respectively.

  13. Impact of aerial infrared roof moisture scans on the U.S. Army's ROOFER program

    NASA Astrophysics Data System (ADS)

    Knehans, Al; Ledford, Jim

    1993-04-01

    The ROOFER program is being used by the U.S. Army to inspect and evaluate its built-up and single-ply membrane roofs. The results of the inspection effort are used to develop an overall roof condition index. The condition of the roof insulation can greatly alter the final condition index. By using an aerial infrared (IR) roof moisture scan, all the insulated roofs at most Army installations can be effectively surveyed in a very short time. The aerial scans have detected numerous areas of wet roof insulation, which has had a profound impact on the results of the ROOFER program. The scans have also provided management personnel with more accurate analysis as to the actual condition of the installation's insulated roofs.

  14. Integration of active and passive cool roof system for attic temperature reduction

    NASA Astrophysics Data System (ADS)

    Yew, Ming Chian; Yew, Ming Kun; Saw, Lip Huat; Durairaj, Rajkumar

    2017-04-01

    The aim of this project is to study the capability of cool roof system in the reduction of heat transmission through metal roof into an attic. The cool roof system is designed in active and passive methods to reduce the thermal loads imposed to a building. Two main features are introduced to this cool roof system, which is thermal insulation coating (TIC) and moving air cavity (MAC) that served as active and passive manner, respectively. For MAC, two designs are introduced. Normal MAC is fabricated by six aluminium tubes whereby each aluminium tube is made up by sticking up of five aluminium cans. While improved MAC is also made by six aluminium tubes whereby each aluminium tube is custom made from steel rods and aluminium foils. MAC provides ventilation and heat reflection under the metal roof before the heat transfer into attic. It also coupled with three solar powered fans to increase heat flow inside the channel. The cool roof that incorporated TIC, MAC with solar powered fans and opened attic inlet showed a significant improvement with a reduction of up to 14 °C in the attic temperature compared to conventional roof system.

  15. Calculation of parameters of combined frame and roof bolting

    NASA Astrophysics Data System (ADS)

    Ivanov, S. I.; Titov, N. V.; Privalov, A. A.; Trunov, I. T.; Sarychev, V. I.

    2017-10-01

    The paper presents the method of calculation of the combined frame and roof bolting. Recommendations on providing joint operation of roof bolting with steel support frames are given. Graphs for determining standard rock movement, as well as for defining proof load on the yielding support, were developed.

  16. 5. ROOF DETAIL, LOOKING EAST TOWARD SECOND FLOOR WAREHOUSE FROM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. ROOF DETAIL, LOOKING EAST TOWARD SECOND FLOOR WAREHOUSE FROM ROOF OF ASSEMBLY AREA. - Ford Motor Company Long Beach Assembly Plant, Assembly Building, 700 Henry Ford Avenue, Long Beach, Los Angeles County, CA

  17. Advanced Insulation for High Performance Cost-Effective Wall, Roof, and Foundation Systems Final Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Costeux, Stephane; Bunker, Shanon

    The objective of this project was to explore and potentially develop high performing insulation with increased R/inch and low impact on climate change that would help design highly insulating building envelope systems with more durable performance and lower overall system cost than envelopes with equivalent performance made with materials available today. The proposed technical approach relied on insulation foams with nanoscale pores (about 100 nm in size) in which heat transfer will be decreased. Through the development of new foaming methods, of new polymer formulations and new analytical techniques, and by advancing the understanding of how cells nucleate, expand andmore » stabilize at the nanoscale, Dow successfully invented and developed methods to produce foams with 100 nm cells and 80% porosity by batch foaming at the laboratory scale. Measurements of the gas conductivity on small nanofoam specimen confirmed quantitatively the benefit of nanoscale cells (Knudsen effect) to increase insulation value, which was the key technical hypotheses of the program. In order to bring this technology closer to a viable semi-continuous/continuous process, the project team modified an existing continuous extrusion foaming process as well as designed and built a custom system to produce 6" x 6" foam panels. Dow demonstrated for the first time that nanofoams can be produced in a both processes. However, due to technical delays, foam characteristics achieved so far fall short of the 100 nm target set for optimal insulation foams. In parallel with the technology development, effort was directed to the determination of most promising applications for nanocellular insulation foam. Voice of Customer (VOC) exercise confirmed that demand for high-R value product will rise due to building code increased requirements in the near future, but that acceptance for novel products by building industry may be slow. Partnerships with green builders, initial launches in smaller markets (e.g. EIFS), and efforts to drive cost down will help acceptance in residential and commercial retrofit and new construction.« less

  18. Quantitative analysis on the urban flood mitigation effect by the extensive green roof system.

    PubMed

    Lee, J Y; Moon, H J; Kim, T I; Kim, H W; Han, M Y

    2013-10-01

    Extensive green-roof systems are expected to have a synergetic effect in mitigating urban runoff, decreasing temperature and supplying water to a building. Mitigation of runoff through rainwater retention requires the effective design of a green-roof catchment. This study identified how to improve building runoff mitigation through quantitative analysis of an extensive green-roof system. Quantitative analysis of green-roof runoff characteristics indicated that the extensive green roof has a high water-retaining capacity response to rainfall of less than 20 mm/h. As the rainfall intensity increased, the water-retaining capacity decreased. The catchment efficiency of an extensive green roof ranged from 0.44 to 0.52, indicating reduced runoff comparing with efficiency of 0.9 for a concrete roof. Therefore, extensive green roofs are an effective storm water best-management practice and the proposed parameters can be applied to an algorithm for rainwater-harvesting tank design. © 2013 Elsevier Ltd. All rights reserved.

  19. Evaluating Cool Impervious Surfaces: Application to an Energy-Efficient Residential Roof and to City Pavements

    NASA Astrophysics Data System (ADS)

    Rosado, Pablo Javier

    heating savings of 4% and electric heating savings of 3%. The slightly positive fractional annual heating energy savings likely resulted from the tile roof's high thermal capacitance, which increased the overnight temperature of the attic air. Thus cool tile roofs should be perceived as a technology that provides energy and environmental benefits during the cooling season as well as the heating season. The second topic investigates the direct and indirect effects of cool pavements on the energy use of California's building stock. First, a simple urban canyon model was developed to calculate the canyon albedo after the user provides the solar position, canyon orientation, and dimensions of the canyon walls, road, and setbacks. Next, a method is presented to correct the values of temperature changes obtained from previous urban climate models to values that would be obtained from canyon geometries that distinguish between road and setbacks (e.g. sidewalk, front yard). The new canyon model is used to scale the temperature changes obtained from a recent urban climate model that simulated the climatological impact of cool pavements on various California cities. The adjusted temperature changes are then combined with building energy simulations to investigate the effect of cool pavements on the cooling, heating, and lighting energy uses of buildings as well as the environmental impact related to these energy uses. Net (direct + indirect) conditioning (cooling + heating) energy savings and environmental savings from cool pavements were smaller in residential buildings than in commercial buildings. Additionally, residential buildings strongly dominate the building stock in all of the evaluated cities. Therefore, even though most cities yielded conditioning energy and environmental savings, they were small due to the minuscule savings from the residential buildings. When increasing the albedo by 0.20 of all public pavements in different California cities, Los Angeles was the city

  20. Establishment of substratum polarity in the blastocoel roof of the Xenopus embryo.

    PubMed

    Nagel, M; Winklbauer, R

    1999-05-01

    The fibronectin fibril matrix on the blastocoel roof of the Xenopus gastrula contains guidance cues that determine the direction of mesoderm cell migration. The underlying guidance-related polarity of the blastocoel roof is established in the late blastula under the influence of an instructive signal from the vegetal half of the embryo, in particular from the mesoderm. Formation of an oriented substratum depends on functional activin and FGF signaling pathways in the blastocoel roof. Besides being involved in tissue polarization, activin and FGF also affect fibronectin matrix assembly. Activin treatment of the blastocoel roof inhibits fibril formation, whereas FGF modulates the structure of the fibril network. The presence of intact fibronectin fibrils is permissive for directional mesoderm migration on the blastocoel roof extracellular matrix.

  1. 4. EAST VIEW OF HEAVILY DETERIORATED SECTION OF SEA WALL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. EAST VIEW OF HEAVILY DETERIORATED SECTION OF SEA WALL LOOKING ACROSS ERODED EASTERN CORNER OF PEA PATCH ISLAND. BUILDING FOUNDATION REMAINS IN FOREGROUND. - Fort Delaware, Sea Wall, Pea Patch Island, Delaware City, New Castle County, DE

  2. Roof sprinkling system sweats down A/C costs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    This article describes a roof spray system which enhances the energy efficiency of a building's HVAC system at a nominal cost in relationship to the benefits it yields. Roof spray cooling is based on the fact that water, when it evaporates, absorbs large amounts of heat. The evaporation of one gallon of water will dissipate about 8500 BTU's of heat; and three fallons of water evaporated over one hour's time offers the same cooling capacity as a two-ton airconditioner operated over the same period. By intermittently spraying its surface with water, a direct evaporative cooling system allows a roof tomore » sweat away the sun's radiant heat, cooling an un-airconditioned building from 10 to 12 degrees mrt and reducing summer electric costs by 25%.« less

  3. Modelling reduction of urban heat load in Vienna by modifying surface properties of roofs

    NASA Astrophysics Data System (ADS)

    Žuvela-Aloise, Maja; Andre, Konrad; Schwaiger, Hannes; Bird, David Neil; Gallaun, Heinz

    2018-02-01

    The study examines the potential of urban roofs to reduce the urban heat island (UHI) effect by changing their reflectivity and implementing vegetation (green roofs) using the example of the City of Vienna. The urban modelling simulations are performed based on high-resolution orography and land use data, climatological observations, surface albedo values from satellite imagery and registry of the green roof potential in Vienna. The modelling results show that a moderate increase in reflectivity of roofs (up to 0.45) reduces the mean summer temperatures in the densely built-up environment by approximately 0.25 °C. Applying high reflectivity materials (roof albedo up to 0.7) leads to average cooling in densely built-up area of approximately 0.5 °C. The green roofs yield a heat load reduction in similar order of magnitude as the high reflectivity materials. However, only 45 % of roof area in Vienna is suitable for greening and the green roof potential mostly applies to industrial areas in city outskirts and is therefore not sufficient for substantial reduction of the UHI effect, particularly in the city centre which has the highest heat load. The strongest cooling effect can be achieved by combining the green roofs with high reflectivity materials. In this case, using 50 or 100 % of the green roof potential and applying high reflectivity materials on the remaining surfaces have a similar cooling effect.

  4. Storm water infiltration in a monitored green roof for hydrologic restoration.

    PubMed

    Palla, A; Sansalone, J J; Gnecco, I; Lanza, L G

    2011-01-01

    The objectives of this study are to provide detailed information about green roof performance in the Mediterranean climate (retained volume, peak flow reduction, runoff delay) and to identify a suitable modelling approach for describing the associated hydrologic response. Data collected during a 13-month monitoring campaign and a seasonal monitoring campaign (September-December 2008) at the green roof experimental site of the University of Genova (Italy) are presented together with results obtained in quantifying the green roof hydrologic performance. In order to examine the green roof hydrologic response, the SWMS_2D model, that solves the Richards' equation for two-dimensional saturated-unsaturated water flow, has been implemented. Modelling results confirm the suitability of the SWMS_2D model to properly describe the hydrologic response of the green roofs. The model adequately reproduces the hydrographs; furthermore, the predicted soil water content profile generally matches the observed values along a vertical profile where measurements are available.

  5. Interior view of the Sheet Metal Shop showing the roof ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view of the Sheet Metal Shop showing the roof trusses and corrugated metal roof covering, view facing northwest - Kahului Cannery, Plant No. 28, Boiler House, Sheet Metal and Electrical Shops, 120 Kane Street, Kahului, Maui County, HI

  6. The joint influence of albedo and insulation on roof performance: An observational study

    DOE PAGES

    Ramamurthy, P.; Sun, T.; Rule, K.; ...

    2015-02-23

    We focus on understanding the temperature and heat flux fields in building roofs, and how they are modulated by the interacting influences of albedo and insulation at annual, seasonal and diurnal scales. High precision heat flux plates and thermocouples were installed over multiple rooftops of varying insulation thickness and albedo in the Northeastern United States to monitor the temperature and the heat flux into and out of the roof structures for a whole year. This analysis shows that while membrane reflectivity (albedo) plays a dominant role in reducing the heat conducted inward through the roof structures during the warmer months,more » insulation thickness becomes the main roof attribute in preventing heat loss from the buildings during colder months. On a diurnal scale, the thermal state of the white roof structures fluctuated little compared to black roof structures; membrane temperature over white roofs ranged between 10 °C and 45 °C during summer months compared to black membranes that ranged between 10 °C and 80 °C. Insulation thickness, apart from reducing the heat conducted through the roof structure, also delayed the transfer of heat, owing to the thermal inertia of the insulation layer. Furthermore, this has important implications for determining the peak heating and cooling times.« less

  7. The joint influence of albedo and insulation on roof performance: An observational study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ramamurthy, P.; Sun, T.; Rule, K.

    We focus on understanding the temperature and heat flux fields in building roofs, and how they are modulated by the interacting influences of albedo and insulation at annual, seasonal and diurnal scales. High precision heat flux plates and thermocouples were installed over multiple rooftops of varying insulation thickness and albedo in the Northeastern United States to monitor the temperature and the heat flux into and out of the roof structures for a whole year. This analysis shows that while membrane reflectivity (albedo) plays a dominant role in reducing the heat conducted inward through the roof structures during the warmer months,more » insulation thickness becomes the main roof attribute in preventing heat loss from the buildings during colder months. On a diurnal scale, the thermal state of the white roof structures fluctuated little compared to black roof structures; membrane temperature over white roofs ranged between 10 °C and 45 °C during summer months compared to black membranes that ranged between 10 °C and 80 °C. Insulation thickness, apart from reducing the heat conducted through the roof structure, also delayed the transfer of heat, owing to the thermal inertia of the insulation layer. Furthermore, this has important implications for determining the peak heating and cooling times.« less

  8. Experimental research on coalbed gas drainage effect and economy of long directional borehole in roof

    NASA Astrophysics Data System (ADS)

    Yang, Huiming; Hu, Liangping

    2017-05-01

    In order to study the coalbed gas drainage effect and economy of long directional roof borehole, 2 boreholes were laid out in Xinji No. 2 mine to analyze its gas drainage and investment costs comparing with high position roof borehole and high position roof roadway. The result indicates that the long directional roof borehole save investment by 44.8% and shorten the construction period by 30%, comparing with high position roof roadway for controlling gas in the working face. Investment slightly less and shorten the construction period by 47.5%, comparing with the roof high position borehole. Therefore, the method of the long directional roof borehole to drain coalbed gas in working face is the most cost-effective.

  9. Field Testing of an Unvented Roof with Fibrous Insulation, Tiles, and Vapor Diffusion Venting

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ueno, K.; Lstiburek, J. W.

    This research is a test implementation of an unvented tile roof assembly in a hot-humid climate (Orlando, FL; Zone 2A), insulated with air permeable insulation (netted and blown fiberglass). Given the localized moisture accumulation and failures seen in previous unvented roof field work, it was theorized that a 'diffusion vent' (water vapor open, but air barrier 'closed') at the highest points in the roof assembly might allow for the wintertime release of moisture, to safe levels. The 'diffusion vent' is an open slot at the ridge and hips, covered with a water-resistant but vapor open (500+ perm) air barrier membrane.more » As a control comparison, one portion of the roof was constructed as a typical unvented roof (self-adhered membrane at ridge). The data collected to date indicate that the diffusion vent roof shows greater moisture safety than the conventional, unvented roof design.« less

  10. The Effects of Infrared-Blocking Pigments and Deck Venting on Stone-Coated Metal Residential Roofs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Miller, William A

    2006-01-01

    Field data show that stone-coated metal shakes and S-mission tile, which exploit the use of infraredblocking color pigments (IrBCPs), along with underside venting reduce the heat flow penetrating the conditioned space of a residence by 70% compared with the amount of heat flow penetrating roofs with conventional asphalt shingles. Stone-coated metal roof products are typically placed on battens and counter-battens and nailed through the battens to the roof deck. The design provides venting on the underside of the metal roof that reduces the heat flow penetrating a home. The Metal Construction Association (MCA) and its affiliate members installed stone-coated metalmore » roofs with shake and S-mission tile profiles and a painted metal shake roof on a fully instrumented attic test assembly at Oak Ridge National Laboratory (ORNL). Measurements of roof, deck, attic, and ceiling temperatures; heat flows; solar reflectance; thermal emittance; and ambient weather were recorded for each of the test roofs and also for an adjacent attic cavity covered with a conventional pigmented and direct nailed asphalt shingle roof. All attic assemblies had ridge and soffit venting; the ridge was open to the underside of the stone-coated metal roofs. A control assembly with a conventional asphalt shingle roof was used for comparing deck and ceiling heat transfer rates.« less

  11. 30 CFR 75.202 - Protection from falls of roof, face and ribs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Protection from falls of roof, face and ribs... Protection from falls of roof, face and ribs. (a) The roof, face and ribs of areas where persons work or travel shall be supported or otherwise controlled to protect persons from hazards related to falls of the...

  12. 30 CFR 75.202 - Protection from falls of roof, face and ribs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Protection from falls of roof, face and ribs... Protection from falls of roof, face and ribs. (a) The roof, face and ribs of areas where persons work or travel shall be supported or otherwise controlled to protect persons from hazards related to falls of the...

  13. 30 CFR 75.202 - Protection from falls of roof, face and ribs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Protection from falls of roof, face and ribs... Protection from falls of roof, face and ribs. (a) The roof, face and ribs of areas where persons work or travel shall be supported or otherwise controlled to protect persons from hazards related to falls of the...

  14. 30 CFR 75.202 - Protection from falls of roof, face and ribs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Protection from falls of roof, face and ribs... Protection from falls of roof, face and ribs. (a) The roof, face and ribs of areas where persons work or travel shall be supported or otherwise controlled to protect persons from hazards related to falls of the...

  15. 30 CFR 75.202 - Protection from falls of roof, face and ribs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Protection from falls of roof, face and ribs... Protection from falls of roof, face and ribs. (a) The roof, face and ribs of areas where persons work or travel shall be supported or otherwise controlled to protect persons from hazards related to falls of the...

  16. The “shape” and “meaning” of the roof arts in Chinese classical architecture

    NASA Astrophysics Data System (ADS)

    Li, Xianda; liu, Yu

    2017-04-01

    This paper takes the “roof” in Chinese classical architecture as the research object. The breakthrough point of this paper would be the perspective of design aesthetics. Through the rational and perceptual analysis of the roof art, this paper would reveal that the roof shape has the double artistic features: “beauty of shape” and “beauty of idea”. This paper would have a comprehensive analysis for the following aspects: the rational method of roof construction, the emotional feeling of the roof construction and the implied meaning of beauty in the roof construction.

  17. Spatial environmental heterogeneity affects plant growth and thermal performance on a green roof.

    PubMed

    Buckland-Nicks, Michael; Heim, Amy; Lundholm, Jeremy

    2016-05-15

    Green roofs provide ecosystem services, including stormwater retention and reductions in heat transfer through the roof. Microclimates, as well as designed features of green roofs, such as substrate and vegetation, affect the magnitude of these services. Many green roofs are partially shaded by surrounding buildings, but the effects of this within-roof spatial environmental heterogeneity on thermal performance and other ecosystem services have not been examined. We quantified the effects of spatial heterogeneity in solar radiation, substrate depth and other variables affected by these drivers on vegetation and ecosystem services in an extensive green roof. Spatial heterogeneity in substrate depth and insolation were correlated with differential growth, survival and flowering in two focal plant species. These effects were likely driven by the resulting spatial heterogeneity in substrate temperature and moisture content. Thermal performance (indicated by heat flux and substrate temperature) was influenced by spatial heterogeneity in vegetation cover and substrate depth. Areas with less insolation were cooler in summer and had greater substrate moisture, leading to more favorable conditions for plant growth and survival. Spatial variation in substrate moisture (7%-26% volumetric moisture content) and temperature (21°C-36°C) during hot sunny conditions in summer could cause large differences in stormwater retention and heat flux within a single green roof. Shaded areas promote smaller heat fluxes through the roof, leading to energy savings, but lower evapotranspiration in these areas should reduce stormwater retention capacity. Spatial heterogeneity can thus result in trade-offs between different ecosystem services. The effects of these spatial heterogeneities are likely widespread in green roofs. Structures that provide shelter from sun and wind may be productively utilized to design higher functioning green roofs and increase biodiversity by providing habitat

  18. [Influence of green roof application on water quantity and quality in urban region].

    PubMed

    Wang, Shu-Min; Li, Xing-Yang; Zhang, Jun-Hua; Yu, Hui; Hao, You-Zhi; Yang, Wan-Yi

    2014-07-01

    Green roof is widely used in advanced stormwater management as a major measure now. Taking Huxi catchment in Chongqing University as the study area, the relationships between green roof installation with runoff volume and water quality in urban region were investigated. The results showed that roof greening in the urban region contributed to reducing the runoff volume and pollution load. In addition, the spatial distribution and area of green roof also had effects on the runoff water quality. With the conditions that the roof area was 25% of the total watershed area, rainfall duration was 15 min and rainfall intensity was 14.8 mm x h(-1), the peak runoff and total runoff volume were reduced by 5.3% and 31%, the pollution loads of total suspended solid (TSS), total phosphorus (TP) and total nitrogen (TN) decreased by 40.0%, 31.6% and 29.8%, their peak concentrations decreased by 21.0%, 16.0% and -12.2%, and the EMCs (event mean concentrations) were cut down by 13.1%, 0.9% and -1.7%, respectively, when all impervious roofs were greened in the research area. With the increase of roof greening rate, the reduction rates of TSS and TP concentrations increased, while the reduction rate of TN concentration decreased on the whole. Much more improvement could be obtained with the use of green roofs near the outlet of the watershed.

  19. Structural changes of green roof growing substrate layer studied by X-ray CT

    NASA Astrophysics Data System (ADS)

    Jelinkova, Vladimira; Sacha, Jan; Dohnal, Michal; Snehota, Michal

    2017-04-01

    Increasing interest in green infrastructure linked with newly implemented legislation/rules/laws worldwide opens up research potential for field of soil hydrology. A better understanding of function of engineered soils involved in green infrastructure solutions such as green roofs or rain garden is needed. A soil layer is considered as a highly significant component of the aforesaid systems. In comparison with a natural soil, the engineered soil is assumed to be the more challenging case due to rapid structure changes early stages after its build-up. The green infrastructure efficiency depends on the physical and chemical properties of the soil, which are, in the case of engineered soils, a function of its initial composition and subsequent soil formation processes. The project presented in this paper is focused on fundamental processes in the relatively thick layer of engineered soil. The initial structure development, during which the pore geometry is altered by the growth of plant roots, water influx, solid particles translocation and other soil formation processes, is investigated with the help of noninvasive imaging technique  X-ray computed tomography. The soil development has been studied on undisturbed soil samples taken periodically from green roof test system during early stages of its life cycle. Two approaches and sample sizes were employed. In the first approach, undisturbed samples (volume of about 63 cm3) were taken each time from the test site and scanned by X-ray CT. In the second approach, samples (volume of about 630 cm3) were permanently installed at the test site and has been repeatedly removed to perform X-ray CT imaging. CT-derived macroporosity profiles reveal significant temporal changes of soil structure. Clogging of pores by fine particles and fissures development are two most significant changes that would affect the green roof system efficiency. This work has been supported by the Ministry of Education, Youth and Sports within

  20. Reliability Analysis of a Green Roof Under Different Storm Scenarios

    NASA Astrophysics Data System (ADS)

    William, R. K.; Stillwell, A. S.

    2015-12-01

    Urban environments continue to face the challenges of localized flooding and decreased water quality brought on by the increasing amount of impervious area in the built environment. Green infrastructure provides an alternative to conventional storm sewer design by using natural processes to filter and store stormwater at its source. However, there are currently few consistent standards available in North America to ensure that installed green infrastructure is performing as expected. This analysis offers a method for characterizing green roof failure using a visual aid commonly used in earthquake engineering: fragility curves. We adapted the concept of the fragility curve based on the efficiency in runoff reduction provided by a green roof compared to a conventional roof under different storm scenarios. We then used the 2D distributed surface water-groundwater coupled model MIKE SHE to model the impact that a real green roof might have on runoff in different storm events. We then employed a multiple regression analysis to generate an algebraic demand model that was input into the Matlab-based reliability analysis model FERUM, which was then used to calculate the probability of failure. The use of reliability analysis as a part of green infrastructure design code can provide insights into green roof weaknesses and areas for improvement. It also supports the design of code that is more resilient than current standards and is easily testable for failure. Finally, the understanding of reliability of a single green roof module under different scenarios can support holistic testing of system reliability.

  1. Evaluation of Green Roof Water Quantity and Quality Performance in an Urban Climate

    EPA Science Inventory

    In this report we present an analysis of water benefits from an array of observed green roof and control (non-vegetated) roof project sites throughout NYC. The projects are located on a variety of building sites and represent a diverse set of available extensive green roof instal...

  2. 6. ROOF OF TURBINE BUILDING AND OF L.P. BOILER ROOM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. ROOF OF TURBINE BUILDING AND OF L.P. BOILER ROOM FROM NORTH END OF TURBINE BUILDING ROOF - Portland General Electric Company, Turbine Building, 1841 Southeast Water Street, Portland, Multnomah County, OR

  3. Retention performance of green roofs in three different climate regions

    NASA Astrophysics Data System (ADS)

    Sims, Andrew W.; Robinson, Clare E.; Smart, Charles C.; Voogt, James A.; Hay, Geoffrey J.; Lundholm, Jeremey T.; Powers, Brandon; O'Carroll, Denis M.

    2016-11-01

    Green roofs are becoming increasingly popular for moderating stormwater runoff in urban areas. This study investigated the impact different climates have on the retention performance of identical green roofs installed in London Ontario (humid continental), Calgary Alberta (semi-arid, continental), and Halifax Nova Scotia (humid, maritime). Drier climates were found to have greater percent cumulative stormwater retention with Calgary (67%) having significantly better percent retention than both London (48%) and Halifax (34%). However, over the same study period the green roof in London retained the greatest depth of stormwater (598 mm), followed by the green roof in Halifax (471 mm) and then Calgary (411 mm). The impact of climate was largest for medium sized storms where the antecedent moisture condition (AMC) at the beginning of a rainfall event governs retention performance. Importantly AMC was a very good predictor of stormwater retention, with similar retention at all three sites for a given AMC, emphasizing that AMC is a relevant indicator of retention performance in any climate. For large rainfall events (i.e., >45 mm) green roof average retention ranged between 16% and 29% in all cities. Overall, drier climates have superior retention due to lower AMC in the media. However, moderate and wet climates still provide substantial total volume reduction benefits.

  4. Unique Roll-Off Roof for Housing 1.3 m Telescope at Devasthal, Nainital

    NASA Astrophysics Data System (ADS)

    Bangia, Tarun

    2017-06-01

    Aryabhatta Research Institute of Observational Sciences (ARIES) had set up a 1.3 m telescope at Devasthal, Nainital, India in the year 2010. Country's largest roll-off roof was indigenously designed, fabricated and installed on top of a building (17 × 8 m) for housing 1.3 m telescope. Telescope was supplied by M/s DFM Engineering Inc., USA to ARIES and was installed in the building with unique roll-off roof to protect it from external environment. Roll-off roof was designed and fabricated considering various parameters and available manpower and resources at ARIES. This paper presents mechanical development work, simple but distinct design approach and innovative selection of materials to economically manufacture roll-off roof of large size (8 × 8 × 4 m) at hilly remote site of Devasthal situated in Central Himalayan region. All operations in the roof viz. opening of shutters and rolling of roof were motorized to facilitate observers during night observations.

  5. A Model of Equilibrium Conditions of Roof Rock Mass Giving Consideration to the Yielding Capacity of Powered Supports

    NASA Astrophysics Data System (ADS)

    Jaszczuk, Marek; Pawlikowski, Arkadiusz

    2017-12-01

    units giving consideration to the load of the caving shield, a model of support unit was used that allows for unequivocal determination of the yielding capacity of the support with consideration given to the height of the unit in use and the change in the inclination of the canopy resulting from the displacement of the roof of the longwall. The yielding capacity of the support unit and its point of application on the canopy was determined using the method of units which allows for the internal forces to be manifested. The weight of the rock mass depends on the geological and mining conditions, for which the shape and dimensions of the rock mass affecting the support unit are determined. The resultant force of the pressure of gob on the gob shield was calculated by assuming that the load may be understood as a pressure of ground on a wall. This required the specification of the volume of the fallen rocks that affect the unit of powered roof supports (Fig. 2). To determine the support of the roof rock mass by the coal seam, experience of the Australian mining industry was used. Experiments regarding the strength properties of coal have exhibited that vertical deformation, at which the highest seam reaction occurs while supporting the roof rock mass, amounts to 0.5% of the longwall's height. The measure of the width of the contact area between the rock mass and the seam is the width of the additional uncovering of the face roof due to spalling of seam topcorners da (Fig. 2). With the above parameters and the value of the modulus of elasticity of coal in mind, the value of the seam's reaction may be estimated using the dependence (2). The vertical component of the goafs' reaction may be determined based on the strength characteristics of the fallen roof, the contact area of the rock mass with the fallen roof and the mean strain of the fallen roof at the area of contact. In the work by Pawlikowski (2014), a research procedure was proposed which encompasses model tests and

  6. 49 CFR 571.118 - Standard No. 118; Power-operated window, partition, and roof panel systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...-operated window, partition, and roof panel systems. S1. Purpose and scope. This standard specifies requirements for power operated window, partition, and roof panel systems to minimize the likelihood of death... Figure 2. Power operated roof panel systems mean moveable panels in the vehicle roof which close by...

  7. 49 CFR 571.118 - Standard No. 118; Power-operated window, partition, and roof panel systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...-operated window, partition, and roof panel systems. S1. Purpose and scope. This standard specifies requirements for power operated window, partition, and roof panel systems to minimize the likelihood of death... Figure 2. Power operated roof panel systems mean moveable panels in the vehicle roof which close by...

  8. 49 CFR 571.118 - Standard No. 118; Power-operated window, partition, and roof panel systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...-operated window, partition, and roof panel systems. S1. Purpose and scope. This standard specifies requirements for power operated window, partition, and roof panel systems to minimize the likelihood of death... Figure 2. Power operated roof panel systems mean moveable panels in the vehicle roof which close by...

  9. 49 CFR 571.118 - Standard No. 118; Power-operated window, partition, and roof panel systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...-operated window, partition, and roof panel systems. S1. Purpose and scope. This standard specifies requirements for power operated window, partition, and roof panel systems to minimize the likelihood of death... Figure 2. Power operated roof panel systems mean moveable panels in the vehicle roof which close by...

  10. 49 CFR 571.118 - Standard No. 118; Power-operated window, partition, and roof panel systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...-operated window, partition, and roof panel systems. S1. Purpose and scope. This standard specifies requirements for power operated window, partition, and roof panel systems to minimize the likelihood of death... Figure 2. Power operated roof panel systems mean moveable panels in the vehicle roof which close by...

  11. Assessment of Soil Arching Factor for Retaining Wall Pile Foundations

    DOT National Transportation Integrated Search

    2017-03-31

    Despite the prevalence of the soldier piles retaining wall systems as temporary and even permanent shoring systems along state highways, relatively little is known on the effect of the foreslope bench width and the slope inclination on the arching ca...

  12. Reducing Heat Gains and Cooling Loads Through Roof Structure Configurations of A House in Medan

    NASA Astrophysics Data System (ADS)

    Handayani Lubis, Irma; Donny Koerniawan, Mochamad

    2018-05-01

    Heat gains and heat losses through building surfaces are the main factors that determine the building’s cooling and heating loads. Roof as a building surface that has the most exposed area to the sun, contribute most of heat gains in the building. Therefore, the amount of solar heat gains on the roofs need to be minimized by roof structure configurations. This research aims to discover the optimization of roof structure configurations (coating material, structure material, inclination, overhang, and insulation) as one of passive design strategies that reduce heat gains and cooling loads of a house in Medan. The result showed that case four, white-painted metal roof combined with 45° roof pitched, 1.5m overhang, and addition of insulation, indicates the minimum heat gains production and the less cooling loads during clear sky day but not in the overcast sky condition. In conclusion, heat gains and cooling loads of a house in Medan could be diminished during clear sky day by the addition of roof coating with high reflectance low solar absorbtance, the slope roof, the extension of wider veranda, and the addition of insulation in the roof structure.

  13. 23. INTERIOR OF TAN 629 HANGAR, TAKEN FROM LOW ROOF, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. INTERIOR OF TAN 629 HANGAR, TAKEN FROM LOW ROOF, FACING NORTHEAST. SHOWS GROUND LEVEL USE OF FLOOR SPACE FOR TEMPORARY STORAGE OF CRATES. MOISTURE ON SURFACE IS FROM LEAKY HANGAR ROOF. - Idaho National Engineering Laboratory, Test Area North, Hangar No. 629, Scoville, Butte County, ID

  14. Scaling of economic benefits from Green Roof implementation in Washington, DC.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Niu, H.; Clark, C. E.; Zhou, J.

    2010-06-01

    Green roof technology is recognized for mitigating stormwater runoff and energy consumption. Methods to overcome the cost gap between green roofs and conventional roofs were recently quantified by incorporating air quality benefits. This study investigates the impact of scaling on these benefits at the city-wide scale using Washington, DC as a test bed because of the proposed targets in the 20-20-20 vision (20 million ft{sup 2} by 2020) articulated by Casey Trees, a nonprofit organization. Building-specific stormwater benefits were analyzed assuming two proposed policy scenarios for stormwater fees ranging from 35 to 50% reduction for green roof implementation. Heat fluxmore » calculations were used to estimate building-specific energy savings for commercial buildings. To assess benefits at the city scale, stormwater infrastructure savings were based on operational savings and size reduction due to reduced stormwater volume generation. Scaled energy infrastructure benefits were calculated using two size reductions methods for air conditioners. Avoided carbon dioxide, nitrogen oxide (NOx), and sulfur dioxide emissions were based on reductions in electricity and natural gas consumption. Lastly, experimental and fugacity-based estimates were used to quantify the NOx uptake by green roofs, which was translated to health benefits using U.S. Environmental Protection Agency models. The results of the net present value (NPV) analysis showed that stormwater infrastructure benefits totaled $1.04 million (M), while fee-based stormwater benefits were $0.22-0.32 M/y. Energy savings were $0.87 M/y, while air conditioner resizing benefits were estimated at $0.02 to $0.04 M/y and avoided emissions benefits (based on current emission trading values) were $0.09 M-0.41 M/y. Over the lifetime of the green roof (40 years), the NPV is about 30-40% less than that of conventional roofs (not including green roof maintenance costs). These considerable benefits, in concert with current and

  15. Scaling of economic benefits from green roof implementation in Washington, DC.

    PubMed

    Niu, Hao; Clark, Corrie; Zhou, Jiti; Adriaens, Peter

    2010-06-01

    Green roof technology is recognized for mitigating stormwater runoff and energy consumption. Methods to overcome the cost gap between green roofs and conventional roofs were recently quantified by incorporating air quality benefits. This study investigates the impact of scaling on these benefits at the city-wide scale using Washington, DC as a test bed because of the proposed targets in the 20-20-20 vision (20 million ft(2) by 2020) articulated by Casey Trees, a nonprofit organization. Building-specific stormwater benefits were analyzed assuming two proposed policy scenarios for stormwater fees ranging from 35 to 50% reduction for green roof implementation. Heat flux calculations were used to estimate building-specific energy savings for commercial buildings. To assess benefits at the city scale, stormwater infrastructure savings were based on operational savings and size reduction due to reduced stormwater volume generation. Scaled energy infrastructure benefits were calculated using two size reductions methods for air conditioners. Avoided carbon dioxide, nitrogen oxide (NO(x)), and sulfur dioxide emissions were based on reductions in electricity and natural gas consumption. Lastly, experimental and fugacity-based estimates were used to quantify the NO(x) uptake by green roofs, which was translated to health benefits using U.S. Environmental Protection Agency models. The results of the net present value (NPV) analysis showed that stormwater infrastructure benefits totaled $1.04 million (M), while fee-based stormwater benefits were $0.22-0.32 M/y. Energy savings were $0.87 M/y, while air conditioner resizing benefits were estimated at $0.02 to $0.04 M/y and avoided emissions benefits (based on current emission trading values) were $0.09 M-0.41 M/y. Over the lifetime of the green roof (40 years), the NPV is about 30-40% less than that of conventional roofs (not including green roof maintenance costs). These considerable benefits, in concert with current and

  16. Oven wall panel construction

    DOEpatents

    Ellison, Kenneth; Whike, Alan S.

    1980-04-22

    An oven roof or wall is formed from modular panels, each of which comprises an inner fabric and an outer fabric. Each such fabric is formed with an angle iron framework and somewhat resilient tie-bars or welded at their ends to flanges of the angle irons to maintain the inner and outer frameworks in spaced disposition while minimizing heat transfer by conduction and permitting some degree of relative movement on expansion and contraction of the module components. Suitable thermal insulation is provided within the module. Panels or skins are secured to the fabric frameworks and each such skin is secured to a framework and projects laterally so as slidingly to overlie the adjacent frame member of an adjacent panel in turn to permit relative movement during expansion and contraction.

  17. 14. View south from first level roof of firing pier. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. View south from first level roof of firing pier. Pitched corrugated metal roof marks location of the frame approach connecting the firing pier to the shop (shown in left distance). - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  18. Mapping the Green Infrastructure potential - and it's water-energy impacts on New York City roof Tops

    NASA Astrophysics Data System (ADS)

    Engström, Rebecka; Destouni, Georgia; Howells, Mark

    2017-04-01

    Green Roofs have the potential to provide multiple services in cities. Besides acting as carbon sinks, providing noise reduction and decreasing air pollution - without requiring any additional "land-use" in a city (only roof-use), green roofs have a quantifiable potential to reduce direct and indirect energy and water use. They enhance the insulating capacity of a conventional residential roof and thereby decrease both cooling demands in summer and heating demands in winter. The former is further mitigated by the cooling effect of evapotranspiration from the roofs In New York City green roofs are additionally a valuable component of reducing "combined sewer overflows", as these roofs can retain storm water. This can improve water quality in the city's rivers as well as decrease the total volume of water treated in the city's wastewater treatment plants, thereby indirectly reduce energy demands. The impacts of green roofs on NYC's water-energy nexus has been initially studied (Engström et. al, forthcoming). The present study expands that work to more comprehensively investigate the potential of this type of nature-based solution in a dense city. By employing Geographical Information Systems analysis, the roof top area of New York City is analysed and roof space suitable for green roofs of varying types (ranging from extensive to intensive) are mapped and quantified. The total green roof area is then connected with estimates of potential water-energy benefits (and costs) of each type of green roof. The results indicate where green roofs can be beneficially installed throughout the city, and quantifies the related impacts on both water and energy use. These outputs can provide policy makers with valuable support when facing investment decisions in green infrastructure, in a city where there is great interest for these types of nature-based solutions.

  19. Survey of the Pagoda Timber Roof in Derneburg Castle

    NASA Astrophysics Data System (ADS)

    Perria, E.; Sieder, M.; Hoyer, S.; Krafczyk, C.

    2017-05-01

    The work analyses the historical roof of Derneburg Castle, in the municipality of Holle, Hildesheim's district, Lower Saxony, Germany. The roof is assembled according to Laves Balken's system (Laves beam's system), developed by the architect Georg Ludwig Friedrich Laves (1788-1864). The system has the peculiarity to consist of beams that are split along the half of the cross section, and maintained diverged by wooden wedges, distributed along the length of the beam. The system increases the height of the beam, and elevates the bending capacity of it (Weber, 1964). The work has been developed in the frame of an interdisciplinary project in the fields of architecture, engineering and photogrammetry. Main aim of the project is the developing of a structural model to understand the load-carrying capacity of Laves Balken's system from the laser-scanning model. For this reason, extensive surveys and photo documentation were collected on three areas of the roof construction, characterized by three peculiar usage of Laves Balken's system. The work presents the survey of the pagoda-roof that covers the tower of the castle, and problems that can be encountered during the survey of very complex timber constructions.

  20. Reconstructing Buildings with Discontinuities and Roof Overhangs from Oblique Aerial Imagery

    NASA Astrophysics Data System (ADS)

    Frommholz, D.; Linkiewicz, M.; Meissner, H.; Dahlke, D.

    2017-05-01

    This paper proposes a two-stage method for the reconstruction of city buildings with discontinuities and roof overhangs from oriented nadir and oblique aerial images. To model the structures the input data is transformed into a dense point cloud, segmented and filtered with a modified marching cubes algorithm to reduce the positional noise. Assuming a monolithic building the remaining vertices are initially projected onto a 2D grid and passed to RANSAC-based regression and topology analysis to geometrically determine finite wall, ground and roof planes. If this should fail due to the presence of discontinuities the regression will be repeated on a 3D level by traversing voxels within the regularly subdivided bounding box of the building point set. For each cube a planar piece of the current surface is approximated and expanded. The resulting segments get mutually intersected yielding both topological and geometrical nodes and edges. These entities will be eliminated if their distance-based affiliation to the defining point sets is violated leaving a consistent building hull including its structural breaks. To add the roof overhangs the computed polygonal meshes are projected onto the digital surface model derived from the point cloud. Their shapes are offset equally along the edge normals with subpixel accuracy by detecting the zero-crossings of the second-order directional derivative in the gradient direction of the height bitmap and translated back into world space to become a component of the building. As soon as the reconstructed objects are finished the aerial images are further used to generate a compact texture atlas for visualization purposes. An optimized atlas bitmap is generated that allows perspectivecorrect multi-source texture mapping without prior rectification involving a partially parallel placement algorithm. Moreover, the texture atlases undergo object-based image analysis (OBIA) to detect window areas which get reintegrated into the building

  1. The use of nipah leaves (Nypa fruticans) as an environmentally friendly roofing material

    NASA Astrophysics Data System (ADS)

    Umar, Muhammad Zakaria; Faslih, Arman; Arsyad, Muhammad; Ikhsan, Ainussalbi Al; Umar, Mazhfia

    2017-09-01

    An environmentally friendly building is a building that cares for the environment. The use of building materials from plants are very beneficial to maintain the climatic conditions of space and one proper example is the roof made from palm leaves. Petoaha Village, located in the District of Abeli, Kendari Municipality has craftsmen specified in creating roof from palm leaves. The purpose of this study to analyze and identify the instruments of labor, materials, and how to create a roof of palm leaves in the Petoaha Village. This research applies a qualitative case study approach. The result shows that the roof of palm leaves is categorized as an environmentally friendly roofing material due to simple working tools, vegetative based material, man power use and preservation process through immersion in sea water.

  2. Development and investigation of the stressed-deformed state of the demountable foundation for support

    NASA Astrophysics Data System (ADS)

    Sabitov, L. S.; Kashapov, N. F.; Gilmanshin, I. R.; Strelkov, Yu M.; Khusainov, D. M.

    2017-09-01

    The development is demountable foundation for support, including separate reinforced concrete blocks in the form of prisms mounted on the surface of the base and pulled together by horizontal strands, and anchor devices for fixing the supports. The reinforced concrete blocks are made in the form of hollow prisms consisting of walls and square bottoms, and the strands are made in the form of bolts that tighten the walls along the top and bottom, while the anchoring devices for fixing the supports are made in the form of anchors on the bottom of the central prism and horizontal spacers between the support and the walls of the prism in its upper part. Numerical studies of the foundation have been carried out and its optimal sizes have been found in the PK Lira SAPR.

  3. The influence of dual-substrate-layer extensive green roofs on rainwater runoff quantity and quality.

    PubMed

    Wang, Xiaoou; Tian, Yimei; Zhao, Xinhua

    2017-08-15

    This study investigates the ability of dual-substrate-layer extensive green roofs to retain rainwater and reduce pollutant leaching. The substrates in dual-substrate-layer green roofs consist of an upper organic nutrition layer for plant growth and a lower inorganic adsorption layer for water retention and pollutant reduction. One traditional single-substrate-layer extensive green roof was built for comparison with dual-substrate-layer green roofs. During the experimental period, dual-substrate-layer green roofs supported better natural vegetation growth, with coverage exceeding 90%, while the coverage in single-substrate-layer green roof was over 80%. Based on the average retention value of the total rainfall for four types of simulated rains (the total rainfall depth (mm) was 43.2, 54.6, 76.2 and 86.4, respectively), the dual-substrate-layer green roofs, which used the mixture of activated charcoal with perlite and vermiculite as the adsorption substrate, possessed better rainfall retention performance (65.9% and 55.4%) than the single-substrate-layer green roof (52.5%). All of the dual-substrate-layer green roofs appeared to be sinks for organics, heavy metals and all forms of nitrogen in all cases, while acted as sources of phosphorus contaminants in the case of heavy rains. In consideration of the factors of water retention, pollution reduction and service life of the green roof, a mixture of activated charcoal and/or pumice with perlite and vermiculite is recommended as the adsorption substrate. The green roofs were able to mitigate mild acid rain, raising the pH from approximately 5.6 in rainfall to 6.5-7.6 in green roof runoff. No signs of a first flush effect for phosphate, total phosphorus, ammonia nitrogen, nitrate nitrogen, total nitrogen, organics, zinc, lead, chromium, manganese, copper, pH or turbidity were found in the green roof runoff. Cost analysis further proved the practicability of dual-substrate-layer green roofs in retaining rainwater, and

  4. 30 CFR 75.209 - Automated Temporary Roof Support (ATRS) systems.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... paragraphs (b) and (c) of this section, an ATRS system shall be used with roof bolting machines and continuous-mining machines with integral roof bolters operated in a working section. The requirements of this paragraph shall be met according to the following schedule: (1) All new machines ordered after March 28...

  5. 30 CFR 75.209 - Automated Temporary Roof Support (ATRS) systems.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... paragraphs (b) and (c) of this section, an ATRS system shall be used with roof bolting machines and continuous-mining machines with integral roof bolters operated in a working section. The requirements of this paragraph shall be met according to the following schedule: (1) All new machines ordered after March 28...

  6. 30 CFR 75.209 - Automated Temporary Roof Support (ATRS) systems.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... paragraphs (b) and (c) of this section, an ATRS system shall be used with roof bolting machines and continuous-mining machines with integral roof bolters operated in a working section. The requirements of this paragraph shall be met according to the following schedule: (1) All new machines ordered after March 28...

  7. Installation, care, and maintenance of wood shake and shingle roofs

    Treesearch

    Tony Bonura; Jack Dwyer; Arnie Nebelsick; Brent Stuart; R. Sam Williams; Christopher Hunt

    2011-01-01

    This article gives general guidelines for selection, installation, finishing, and maintenance of wood shake and shingle roofs. The authors have gathered information from a variety of sources: research publications on wood finishing, technical data sheets from paint manufacturers, installation instructions for shake and shingle roofs, and interviews with experts having...

  8. Plant Species and Functional Group Combinations Affect Green Roof Ecosystem Functions

    PubMed Central

    Lundholm, Jeremy; MacIvor, J. Scott; MacDougall, Zachary; Ranalli, Melissa

    2010-01-01

    Background Green roofs perform ecosystem services such as summer roof temperature reduction and stormwater capture that directly contribute to lower building energy use and potential economic savings. These services are in turn related to ecosystem functions performed by the vegetation layer such as radiation reflection and transpiration, but little work has examined the role of plant species composition and diversity in improving these functions. Methodology/Principal Findings We used a replicated modular extensive (shallow growing- medium) green roof system planted with monocultures or mixtures containing one, three or five life-forms, to quantify two ecosystem services: summer roof cooling and water capture. We also measured the related ecosystem properties/processes of albedo, evapotranspiration, and the mean and temporal variability of aboveground biomass over four months. Mixtures containing three or five life-form groups, simultaneously optimized several green roof ecosystem functions, outperforming monocultures and single life-form groups, but there was much variation in performance depending on which life-forms were present in the three life-form mixtures. Some mixtures outperformed the best monocultures for water capture, evapotranspiration, and an index combining both water capture and temperature reductions. Combinations of tall forbs, grasses and succulents simultaneously optimized a range of ecosystem performance measures, thus the main benefit of including all three groups was not to maximize any single process but to perform a variety of functions well. Conclusions/Significance Ecosystem services from green roofs can be improved by planting certain life-form groups in combination, directly contributing to climate change mitigation and adaptation strategies. The strong performance by certain mixtures of life-forms, especially tall forbs, grasses and succulents, warrants further investigation into niche complementarity or facilitation as mechanisms

  9. Plant species and functional group combinations affect green roof ecosystem functions.

    PubMed

    Lundholm, Jeremy; Macivor, J Scott; Macdougall, Zachary; Ranalli, Melissa

    2010-03-12

    Green roofs perform ecosystem services such as summer roof temperature reduction and stormwater capture that directly contribute to lower building energy use and potential economic savings. These services are in turn related to ecosystem functions performed by the vegetation layer such as radiation reflection and transpiration, but little work has examined the role of plant species composition and diversity in improving these functions. We used a replicated modular extensive (shallow growing- medium) green roof system planted with monocultures or mixtures containing one, three or five life-forms, to quantify two ecosystem services: summer roof cooling and water capture. We also measured the related ecosystem properties/processes of albedo, evapotranspiration, and the mean and temporal variability of aboveground biomass over four months. Mixtures containing three or five life-form groups, simultaneously optimized several green roof ecosystem functions, outperforming monocultures and single life-form groups, but there was much variation in performance depending on which life-forms were present in the three life-form mixtures. Some mixtures outperformed the best monocultures for water capture, evapotranspiration, and an index combining both water capture and temperature reductions. Combinations of tall forbs, grasses and succulents simultaneously optimized a range of ecosystem performance measures, thus the main benefit of including all three groups was not to maximize any single process but to perform a variety of functions well. Ecosystem services from green roofs can be improved by planting certain life-form groups in combination, directly contributing to climate change mitigation and adaptation strategies. The strong performance by certain mixtures of life-forms, especially tall forbs, grasses and succulents, warrants further investigation into niche complementarity or facilitation as mechanisms governing biodiversity-ecosystem functioning relationships in green

  10. Cooler Tile-Roofed Buildings with Near-Infrared-ReflectiveNon-white Coatings

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Levinson, Ronnen; Akbari, Hashem; Reilly, Joeseph C.

    Owners of homes with pitched roofs visible from ground leveloften prefer non-white roofing products for aesthetic considerations.Non-white, near-infrared-reflective architectural coatings can be appliedin-situ to pitched concrete or clay tile roofs to reduce tiletemperature, building heat gain, and cooling power demand, whilesimultaneously improving the roof s appearance. Scale model measurementsof building temperatures and heat-flux were combined with solar andcooling energy use data to estimate the effects of such cool roofcoatings in various California data. Under typical conditions e.g., 1 kWm-2 summer afternoon insolation, R-11 attic insulation, no radiantbarrier, and a 0.3 reduction in solar absorptance absolute reductions inroof surface temperature, atticmore » air temperature, and ceiling heat fluxare about 12 K, 6.2 K, and 3.7 W m-2, respectively. For a typical 1,500ft2 (139 m2) house with R-11 attic insulation and no radiant barrier,reducing roof absorptance by 0.3 yields whole-house peak power savings of230, 210, and 210 W in Fresno, San Bernardino, and San Diego,respectively. The corresponding absolute and fractional cooling energysavings are 92 kWh yr-1 (5 percent), 67 kWh yr-1 (6 percent), and 8 kWhyr-1 (1 percent), respectively. These savings are about half thosepreviously reported for houses with non-tile roofs. With theseassumptions, the statewide peak cooling power and annual cooling energyreductions would be 240 MW and 63 GWh yr-1, respectively. These energysavings would reduce annual emissions from California power plants by 35kilotonnes CO2, 11 tonnes NOx,and 0.86 tonnes SOx. The economic value ofcooling energy savings is well below the cost of coating a tile roof, butthe simple payback times for using cool pigments in a rooftile coatingare modest (5-7 years) in the hot climates of Fresno and SanBernardino.« less

  11. a Line-Based 3d Roof Model Reconstruction Algorithm: Tin-Merging and Reshaping (tmr)

    NASA Astrophysics Data System (ADS)

    Rau, J.-Y.

    2012-07-01

    Three-dimensional building model is one of the major components of a cyber-city and is vital for the realization of 3D GIS applications. In the last decade, the airborne laser scanning (ALS) data is widely used for 3D building model reconstruction and object extraction. Instead, based on 3D roof structural lines, this paper presents a novel algorithm for automatic roof models reconstruction. A line-based roof model reconstruction algorithm, called TIN-Merging and Reshaping (TMR), is proposed. The roof structural line, such as edges, eaves and ridges, can be measured manually from aerial stereo-pair, derived by feature line matching or inferred from ALS data. The originality of the TMR algorithm for 3D roof modelling is to perform geometric analysis and topology reconstruction among those unstructured lines and then reshapes the roof-type using elevation information from the 3D structural lines. For topology reconstruction, a line constrained Delaunay Triangulation algorithm is adopted where the input structural lines act as constraint and their vertex act as input points. Thus, the constructed TINs will not across the structural lines. Later at the stage of Merging, the shared edge between two TINs will be check if the original structural line exists. If not, those two TINs will be merged into a polygon. Iterative checking and merging of any two neighboured TINs/Polygons will result in roof polygons on the horizontal plane. Finally, at the Reshaping stage any two structural lines with fixed height will be used to adjust a planar function for the whole roof polygon. In case ALS data exist, the Reshaping stage can be simplified by adjusting the point cloud within the roof polygon. The proposed scheme reduces the complexity of 3D roof modelling and makes the modelling process easier. Five test datasets provided by ISPRS WG III/4 located at downtown Toronto, Canada and Vaihingen, Germany are used for experiment. The test sites cover high rise buildings and residential

  12. Plant functional traits predict green roof ecosystem services.

    PubMed

    Lundholm, Jeremy; Tran, Stephanie; Gebert, Luke

    2015-02-17

    Plants make important contributions to the services provided by engineered ecosystems such as green roofs. Ecologists use plant species traits as generic predictors of geographical distribution, interactions with other species, and ecosystem functioning, but this approach has been little used to optimize engineered ecosystems. Four plant species traits (height, individual leaf area, specific leaf area, and leaf dry matter content) were evaluated as predictors of ecosystem properties and services in a modular green roof system planted with 21 species. Six indicators of ecosystem services, incorporating thermal, hydrological, water quality, and carbon sequestration functions, were predicted by the four plant traits directly or indirectly via their effects on aggregate ecosystem properties, including canopy density and albedo. Species average height and specific leaf area were the most useful traits, predicting several services via effects on canopy density or growth rate. This study demonstrates that easily measured plant traits can be used to select species to optimize green roof performance across multiple key services.

  13. Drought versus heat: What's the major constraint on Mediterranean green roof plants?

    PubMed

    Savi, Tadeja; Dal Borgo, Anna; Love, Veronica L; Andri, Sergio; Tretiach, Mauro; Nardini, Andrea

    2016-10-01

    Green roofs are gaining momentum in the arid and semi-arid regions due to their multiple benefits as compared with conventional roofs. One of the most critical steps in green roof installation is the selection of drought and heat tolerant species that can thrive under extreme microclimate conditions. We monitored the water status, growth and survival of 11 drought-adapted shrub species grown on shallow green roof modules (10 and 13cm deep substrate) and analyzed traits enabling plants to cope with drought (symplastic and apoplastic resistance) and heat stress (root membrane stability). The physiological traits conferring efficiency/safety to the water transport system under severe drought influenced plant water status and represent good predictors of both plant water use and growth rates over green roofs. Moreover, our data suggest that high substrate temperature represents a stress factor affecting plant survival to a larger extent than drought per se. In fact, the major cause influencing seedling survival on shallow substrates was the species-specific root resistance to heat, a single and easy measurable trait that should be integrated into the methodological framework for screening and selection of suitable shrub species for roof greening in the Mediterranean. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Temporal variations in the potential hydrological performance of extensive green roof systems

    NASA Astrophysics Data System (ADS)

    De-Ville, Simon; Menon, Manoj; Stovin, Virginia

    2018-03-01

    Existing literature provides contradictory information about variation in potential green roof hydrological performance over time. This study has evaluated a long-term hydrological monitoring record from a series of extensive green roof test beds to identify long-term evolutions and sub-annual (seasonal) variations in potential hydrological performance. Monitoring of nine differently-configured extensive green roof test beds took place over a period of 6 years in Sheffield, UK. Long-term evolutions and sub-annual trends in maximum potential retention performance were identified through physical monitoring of substrate field capacity over time. An independent evaluation of temporal variations in detention performance was undertaken through the fitting of reservoir-routing model parameters. Aggregation of the resulting retention and detention variations permitted the prediction of extensive green roof hydrological performance in response to a 1-in-30-year 1-h summer design storm for Sheffield, UK, which facilitated the comparison of multi and sub-annual hydrological performance variations. Sub-annual (seasonal) variation was found to be significantly greater than long-term evolution. Potential retention performance increased by up to 12% after 5-years, whilst the maximum sub-annual variation in potential retention was 27%. For vegetated roof configurations, a 4% long-term improvement was observed for detention performance, compared to a maximum 63% sub-annual variation. Consistent long-term reductions in detention performance were observed in unvegetated roof configurations, with a non-standard expanded-clay substrate experiencing a 45% reduction in peak attenuation over 5-years. Conventional roof configurations exhibit stable long-term hydrological performance, but are nonetheless subject to sub-annual variation.

  15. European Foundation Designs for Seasonally Frozen Ground

    DTIC Science & Technology

    1992-03-01

    104 173. Design thermal conductivity of mineral wool for frost protection...inside of theo - foundation wall, consisted of 50 mm of Rockwool o3 wallo -"o 0 ° (a mineral wool ). This insulation guides heat from the house down...Thermal Insulation Laboratory 1982.) by introducing mineral wool (Fig. 49c) gives a Table 4. Relationship between floor surface tempera- further slight

  16. Roof Type Selection Based on Patch-Based Classification Using Deep Learning for High Resolution Satellite Imagery

    NASA Astrophysics Data System (ADS)

    Partovi, T.; Fraundorfer, F.; Azimi, S.; Marmanis, D.; Reinartz, P.

    2017-05-01

    3D building reconstruction from remote sensing image data from satellites is still an active research topic and very valuable for 3D city modelling. The roof model is the most important component to reconstruct the Level of Details 2 (LoD2) for a building in 3D modelling. While the general solution for roof modelling relies on the detailed cues (such as lines, corners and planes) extracted from a Digital Surface Model (DSM), the correct detection of the roof type and its modelling can fail due to low quality of the DSM generated by dense stereo matching. To reduce dependencies of roof modelling on DSMs, the pansharpened satellite images as a rich resource of information are used in addition. In this paper, two strategies are employed for roof type classification. In the first one, building roof types are classified in a state-of-the-art supervised pre-trained convolutional neural network (CNN) framework. In the second strategy, deep features from deep layers of different pre-trained CNN model are extracted and then an RBF kernel using SVM is employed to classify the building roof type. Based on roof complexity of the scene, a roof library including seven types of roofs is defined. A new semi-automatic method is proposed to generate training and test patches of each roof type in the library. Using the pre-trained CNN model does not only decrease the computation time for training significantly but also increases the classification accuracy.

  17. Dermal exposure and urinary 1-hydroxypyrene among asphalt roofing workers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McClean, M.D.; Rinehart, R.D.; Sapkota, A.

    2007-07-01

    The primary objective of this study was to identify significant determinants of dermal exposure to polycyclic aromatic compounds (PACs) among asphalt roofing workers and use urinary 1-hydroxyprene (1-OHP) measurements to evaluate the effect of dermal exposure on total absorbed dose. The study population included 26 asphalt roofing workers who performed three primary tasks: tearing off old roofs, putting down new roofs, and operating the kettle at ground level. During multiple consecutive work shifts, dermal patch samples were collected from the underside of each worker's wrists and were analyzed for PACs, pyrene, and benzo(a)pyrene (BAP). During the same work week, urinemore » samples were collected at pre-shift, post-shift, and bedtime each day and were analyzed for 1-OHP (205 urine samples). Linear mixed effects models were used to evaluate the dermal measurements for the purpose of identifying important determinants of exposure, and to evaluate urinary 1-OHP measurements for the purpose of identifying important determinants of total absorbed dose. Dermal exposures to PAC, pyrene, and BAP were found to vary significantly by roofing task and by the presence of an old coal tar pitch roof. For each of the three analytes, the adjusted mean dermal exposures associated with tear-off were approximately four times higher than exposures associated with operating the kettle. Exposure to coal tar pitch was associated with a 6-fold increase in PAC exposure, an 8-fold increase in pyrene exposure and a 35-fold increase in BAP exposure. The presence of coal tar pitch was the primary determinant of dermal exposure, particularly for exposure to BAP. However, the task-based differences that were observed while controlling for pitch suggest that exposure to asphalt also contributes to dermal exposures.« less

  18. Comparison of Software Models for Energy Savings from Cool Roofs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    New, Joshua Ryan; Miller, William A; Huang, Yu

    2014-01-01

    A web-based Roof Savings Calculator (RSC) has been deployed for the United States Department of Energy as an industry-consensus tool to help building owners, manufacturers, distributors, contractors and researchers easily run complex roof and attic simulations. This tool employs modern web technologies, usability design, and national average defaults as an interface to annual simulations of hour-by-hour, whole-building performance using the world-class simulation tools DOE-2.1E and AtticSim in order to provide estimated annual energy and cost savings. In addition to cool reflective roofs, RSC simulates multiple roof and attic configurations including different roof slopes, above sheathing ventilation, radiant barriers, low-emittance roofmore » surfaces, duct location, duct leakage rates, multiple substrate types, and insulation levels. A base case and energy-efficient alternative can be compared side-by-side to estimate monthly energy. RSC was benchmarked against field data from demonstration homes in Ft. Irwin, California; while cooling savings were similar, heating penalty varied significantly across different simulation engines. RSC results reduce cool roofing cost-effectiveness thus mitigating expected economic incentives for this countermeasure to the urban heat island effect. This paper consolidates comparison of RSC s projected energy savings to other simulation engines including DOE-2.1E, AtticSim, Micropas, and EnergyPlus, and presents preliminary analyses. RSC s algorithms for capturing radiant heat transfer and duct interaction in the attic assembly are considered major contributing factors to increased cooling savings and heating penalties. Comparison to previous simulation-based studies, analysis on the force multiplier of RSC cooling savings and heating penalties, the role of radiative heat exchange in an attic assembly, and changes made for increased accuracy of the duct model are included.« less

  19. Estimation of the amount of asbestos-cement roofing in Poland.

    PubMed

    Wilk, Ewa; Krówczyńska, Małgorzata; Pabjanek, Piotr; Mędrzycki, Piotr

    2017-05-01

    The unique set of physical and chemical properties has led to many industrial applications of asbestos worldwide; one of them was roof covering. Asbestos is harmful to human health, and therefore its use was legally forbidden. Since in Poland there is no adequate data on the amount of asbestos-cement roofing, the objective of this study was to estimate its quantity on the basis of physical inventory taking with the use of aerial imagery, and the application of selected statistical features. Data pre-processing and analysis was executed in R Statistical Environment v. 3.1.0. Best random forest models were computed; model explaining 72.9% of the variance was subsequently used to prepare the prediction map of the amount of asbestos-cement roofing in Poland. Variables defining the number of farms, number and age of buildings, and regional differences were crucial for the analysis. The total amount of asbestos roofing in Poland was estimated at 738,068,000 m 2 (8.2m t). It is crucial for the landfill development programme, financial resources distribution, and application of monitoring policies.

  20. A parametric study of the thermal performance of green roofs in different climates through energy modeling

    NASA Astrophysics Data System (ADS)

    Mukherjee, Sananda

    In recent years, there has been great interest in the potential of green roofs as an alternative roofing option to reduce the energy consumed by individual buildings as well as mitigate large scale urban environmental problems such as the heat island effect. There is a widespread recognition and a growing literature of measured data that suggest green roofs can reduce building energy consumption. This thesis investigates the potential of green roofs in reducing the building energy loads and focuses on how the different parameters of a green roof assembly affect the thermal performance of a building. A green roof assembly is modeled in Design Builder- a 3D graphical design modeling and energy use simulation program (interface) that uses the EnergyPlus simulation engine, and the simulated data set thus obtained is compared to field experiment data to validate the roof assembly model on the basis of how accurately it simulates the behavior of a green roof. Then the software is used to evaluate the thermal performance of several green roof assemblies under three different climate types, looking at the whole building energy consumption. For the purpose of this parametric simulation study, a prototypical single story small office building is considered and one parameter of the green roof is altered for each simulation run in order to understand its effect on building's energy loads. These parameters include different insulation thicknesses, leaf area indices (LAI) and growing medium or soil depth, each of which are tested under the three different climate types. The energy use intensities (EUIs), the peak and annual heating and cooling loads resulting from the use of these green roof assemblies are compared with each other and to a cool roof base case to determine the energy load reductions, if any. The heat flux through the roof is also evaluated and compared. The simulation results are then organized and finally presented as a decision support tool that would

  1. Green roof impact on the hydrological cycle components

    NASA Astrophysics Data System (ADS)

    Lamera, Carlotta; Rulli, Maria Cristina; Becciu, Gianfranco; Rosso, Renzo

    2013-04-01

    In the last decades the importance of storm water management in urban areas has increased considerably, due to both urbanization extension and to a greater concern for environment pollution. Traditional storm water control practices, based on the "all to the sewer" attitude, rely on conveyance to route storm water runoff from urban impervious surfaces towards the nearby natural water bodies. In recent years, infiltration facilities are receiving an increasing attention, due to their particular efficiency in restoring a balance in hydrological cycle quite equal to quite pre-urbanization condition. In particular, such techniques are designed to capture, temporarily retain and infiltrate storm water, promote evapotranspiration and harvest water at the source, encouraging in general evaporation, evapotranspiration, groundwater recharge and the re-use of storm water. Green roofs are emerging as an increasingly popular Sustainable Urban Drainage Systems (SUDS) technique for urban storm water management. Indeed, they are able to operate hydrologic control over storm water runoff: they allow a significant reduction of peak flows and runoff volumes collected by drainage system, with a consequent reduction of flooding events and pollution masses discharges by CSO. Furthermore green roofs have a positive influence on the microclimate in urban areas by helping in lower urban air temperatures and mitigate the heat island effect. Last but not least, they have the advantage of improving the thermal insulation of buildings, with significant energy savings. A detailed analysis of the hydrological dynamics, connected both with the characteristics of the climatic context and with the green roof technical design, is essential in order to obtain a full characterization of the hydrologic behavior of a green roof system and its effects on the urban water cycle components. The purpose of this paper is to analysis the hydrological effects and urban benefits of the vegetation cover of a

  2. Habitat connectivity and local conditions shape taxonomic and functional diversity of arthropods on green roofs.

    PubMed

    Braaker, Sonja; Obrist, Martin Karl; Ghazoul, Jaboury; Moretti, Marco

    2017-05-01

    Increasing development of urban environments creates high pressure on green spaces with potential negative impacts on biodiversity and ecosystem services. There is growing evidence that green roofs - rooftops covered with vegetation - can contribute mitigate the loss of urban green spaces by providing new habitats for numerous arthropod species. Whether green roofs can contribute to enhance taxonomic and functional diversity and increase connectivity across urbanized areas remains, however, largely unknown. Furthermore, only limited information is available on how environmental conditions shape green roof arthropod communities. We investigated the community composition of arthropods (Apidae, Curculionidae, Araneae and Carabidae) on 40 green roofs and 40 green sites at ground level in the city of Zurich, Switzerland. We assessed how the site's environmental variables (such as area, height, vegetation, substrate and connectivity among sites) affect species richness and functional diversity using generalized linear models. We used an extension of co-inertia analysis (RLQ) and fourth-corner analysis to highlight the mechanism underlying community assemblages across taxonomic groups on green roof and ground communities. Species richness was higher at ground-level sites, while no difference in functional diversity was found between green roofs and ground sites. Green roof arthropod diversity increased with higher connectivity and plant species richness, irrespective of substrate depth, height and area of green roofs. The species trait analysis reviewed the mechanisms related to the environmental predictors that shape the species assemblages of the different taxa at ground and roof sites. Our study shows the important contribution of green roofs in maintaining high functional diversity of arthropod communities across different taxonomic groups, despite their lower species richness compared with ground sites. Species communities on green roofs revealed to be characterized

  3. Performance Evaluation of Advanced Retrofit Roof Technologies Using Field-Test Data Phase Three Final Report, Volume 1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Biswas, Kaushik; Childs, Phillip W; Atchley, Jerald Allen

    2014-05-01

    This article presents various metal roof configurations that were tested at Oak Ridge National Laboratory in Tennessee, U.S.A. between 2009 and 2013, and describes their potential for reducing the attic-generated space conditioning loads. These roofs contained different combinations of phase change material, rigid insulation, low emittance surface and above-sheathing ventilation, with standing-seam metal panels on top. These roofs were designed to be installed on existing roofs decks, or on top of asphalt shingles for retrofit construction. All the tested roofs showed the potential for substantial energy savings compared to an asphalt shingle roof, which was used as a control formore » comparison. The roofs were constructed on a series of adjacent attics separated at the gables using thick foam insulation. The attics were built on top of a conditioned room. All attics were vented at the soffit and ridge. The test roofs and attics were instrumented with an array of thermocouples. Heat flux transducers were installed in the roof deck and attic floor (ceiling) to measure the heat flows through the roof and between the attic and conditioned space below. Temperature and heat flux data were collected during the heating, cooling and swing seasons over a 3 year period. Data from previous years of testing have been published. Here, data from the latest roof configurations being tested in year 3 of the project are presented. All test roofs were highly effective in reducing the heat flows through the roof and ceiling, and in reducing the diurnal attic temperature fluctuations.« less

  4. Building America Case Study: Field Testing an Unvented Roof with Asphalt Shingles in a Cold Climate, Boilingbrook, Illinois

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    2015-09-01

    Insulating roofs with dense-pack cellulose (instead of spray foam) has moisture risks, but is a lower cost approach. If moisture risks could be addressed, buildings could benefit from retrofit options, and the ability to bring HVAC systems within the conditioned space. Test houses with unvented roof assemblies were built to measure long-term moisture performance, in the Chicago area (5A) and the Houston area (2A). The Chicago-area test bed had seven experimental rafter bays, including a 'control' vented compact roof, and six unvented roof variants with cellulose or fiberglass insulation. The interior was run at 50% RH. All roofs except themore » vented cathedral assembly experienced wood moisture contents and RH levels high enough to constitute failure. Disassembly at the end of the experiment showed that the unvented fiberglass roofs had wet sheathing and mold growth. In contrast, the cellulose roofs only had slight issues, such as rusted fasteners and sheathing grain raise. The Houston-area roof was an unvented attic insulated with spray-applied fiberglass. Most ridges and hips were built with a 'diffusion vent' detail, capped with vapor permeable roof membrane. Some ridge sections were built as a conventional unvented roof, as a control. In the control unvented roofs, roof peak RHs reached high levels in the first winter; as exterior conditions warmed, RHs quickly fell. In contrast, the diffusion vent roofs had drier conditions at the roof peak in wintertime, but during the summer, RHs and MCs were higher than the unvented roof (albeit in the safe range).« less

  5. Interpretation of the Seattle uplift, Washington, as a passive-roof duplex

    USGS Publications Warehouse

    Brocher, T.M.; Blakely, R.J.; Wells, R.E.

    2004-01-01

    We interpret seismic lines and a wide variety of other geological and geophysical data to suggest that the Seattle uplift is a passive-roof duplex. A passive-roof duplex is bounded top and bottom by thrust faults with opposite senses of vergence that form a triangle zone at the leading edge of the advancing thrust sheet. In passive-roof duplexes the roof thrust slips only when the floor thrust ruptures. The Seattle fault is a south-dipping reverse fault forming the leading edge of the Seattle uplift, a 40-km-wide fold-and-thrust belt. The recently discovered, north-dipping Tacoma reverse fault is interpreted as a back thrust on the trailing edge of the belt, making the belt doubly vergent. Floor thrusts in the Seattle and Tacoma fault zones, imaged as discontinuous reflections, are interpreted as blind faults that flatten updip into bedding plane thrusts. Shallow monoclines in both the Seattle and Tacoma basins are interpreted to overlie the leading edges of thrust-bounded wedge tips advancing into the basins. Across the Seattle uplift, seismic lines image several shallow, short-wavelength folds exhibiting Quaternary or late Quaternary growth. From reflector truncation, several north-dipping thrust faults (splay thrusts) are inferred to core these shallow folds and to splay upward from a shallow roof thrust. Some of these shallow splay thrusts ruptured to the surface in the late Holocene. Ages from offset soils in trenches across the fault scarps and from abruptly raised shorelines indicate that the splay, roof, and floor thrusts of the Seattle and Tacoma faults ruptured about 1100 years ago.

  6. Impact of zinc roofing on urban runoff pollutant loads: the case of Paris.

    PubMed

    Gromaire, M C; Chebbo, G; Constant, A

    2002-01-01

    Previous research on the Marais catchment in Paris demonstrated the very high zinc and cadmium contamination of runoff from zinc roofing. Thus further investigations were aimed at evaluating the relative importance of this type of roofing in Paris and its potential contribution to zinc and cadmium loads in wet weather flows. According to these results, about 40% of the surface of roofs in Paris is covered with rolled zinc (1016 ha), and this proportion is not likely to vary significantly in the next years, due to architectural rules. The Zn and Cd concentrations measured in runoff from these roofs are in accordance with literature

  7. ATTENUATION OF SIMULATED FALLOUT RADIATION BY THE ROOF OF A CONCRETE BLOCKHOUSE

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schmoke, M.A.; Rexroad, R.E.

    1961-08-01

    An experiment was carried out to verify theoretical calculations of the effect of roof thickness on the radiation level inside a concrete blockhouse from a plane of gamma radiation on the roof. (auth)

  8. Impacts of shape and height of upstream roof on airflow and pollutant dispersion inside an urban street canyon.

    PubMed

    Huang, Yuan-Dong; He, Wen-Rong; Kim, Chang-Nyung

    2015-02-01

    A two-dimensional numerical model for simulating flow and pollutant dispersion in an urban street canyon is firstly developed using the FLUENT code and then validated against the wind tunnel results. After this, the flow field and pollutant dispersion inside an urban street canyon with aspect ratio W/H = 1 are examined numerically considering five different shapes (vaulted, trapezoidal, slanted, upward wedged, and downward wedged roofs) as well as three different roof height to building height ratios (Z H /H = 1/6, 1/3, and 1/2) for the upstream building roof. The results obtained reveal that the shape and height of an upstream roof have significant influences on flow pattern and pollutant distribution in an urban canyon. A large single clockwise vortex is generated in the canyon for the vaulted upstream roof at Z H /H = 1/6, 1/3, and 1/2, the trapezoidal and downward wedged roofs at Z H /H = 1/6 and 1/3, and the slanted and upward wedged roofs at Z H /H = 1/6, while a main clockwise vortex and a secondary counterclockwise vortex are established for the trapezoidal and downward wedged roofs at Z H /H = 1/2 and the slanted and upward wedged roofs at Z H /H = 1/3 and 1/2. In the one-vortex flow regime, the clockwise vortex moves upward and grows in size with increasing upstream roof height for the vaulted, trapezoidal, and downward wedged roofs. In the two-vortex flow regime, the size and rotational velocity of both upper clockwise and lower counterclockwise vortices increase with the upstream roof height for the slanted and upward wedged roofs. At Z H /H = 1/6, the pollution levels in the canyon are close among all the upstream roof shapes studied. At Z H /H = 1/3, the pollution levels in the canyon for the upward wedged roof and slanted roof are much higher than those for the vaulted, trapezoidal, and downward wedged roofs. At Z H /H = 1/2, the lowest pollution level appears in the canyon for the vaulted upstream roof, while

  9. Summer temperatures of roof assemblies using western redcedar, wood-thermoplastic composite, or fiberglass shingles

    Treesearch

    Jerrold E. Winandy; H. Michael Barnes; Robert H. Falk

    2004-01-01

    For over 10 years, the Forest Products Laboratory has been monitoring the temperature histories of roof sheathing, roof rafters, and unventilated attics in outdoor attic structures that simulate typical light-framed construction. This report briefly summarizes findings from the roof temperature assessment project on black and white fiberglass shingles conducted from...

  10. Field Evaluation of Four Novel Roof Designs for Energy-Efficient Manufactured Homes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Levy, E.; Dentz, J.; Ansanelli, E.

    2015-12-03

    "9A five-bay roof test structure was built, instrumented and monitored in an effort to determine through field testing and analysis the relative contributions of select technologies toward reducing energy use in new manufactured homes. The roof structure in Jamestown, California was designed to examine how differences in roof construction impact space conditioning loads, wood moisture content and attic humidity levels. Conclusions are drawn from the data on the relative energy and moisture performance of various configurations of vented and sealed attics.

  11. Field Evaluation of Four Novel Roof Designs for Energy-Efficient Manufactured Homes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Levy, E.; Dentz, J.; Ansanelli, E.

    2015-12-01

    A five-bay roof test structure was built, instrumented and monitored in an effort to determine through field testing and analysis the relative contributions of select technologies toward reducing energy use in new manufactured homes. The roof structure in Jamestown, California was designed to examine how differences in roof construction impact space conditioning loads, wood moisture content and attic humidity levels. Conclusions are drawn from the data on the relative energy and moisture performance of various configurations of vented and sealed attics.

  12. Technology Solutions Case Study: Field Testing an Unvented Roof with Asphalt Shingles in a Cold Climate

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    K. Ueno and J. Lstiburek

    2015-09-01

    Test houses with unvented roof assemblies were built to measure long-term moisture performance, in the Chicago area (5A) and the Houston area (2A). The Chicago-area test bed had seven experimental rafter bays, including a "control" vented compact roof, and six unvented roof variants with cellulose or fiberglass insulation. The interior was run at 50% RH. All roofs except the vented cathedral assembly experienced wood moisture contents and RH levels high enough to constitute failure. Disassembly at the end of the experiment showed that the unvented fiberglass roofs had wet sheathing and mold growth. In contrast, the cellulose roofs only hadmore » slight issues, such as rusted fasteners and sheathing grain raise.« less

  13. Intercondylar roof impingement pressure after anterior cruciate ligament reconstruction in a porcine model.

    PubMed

    Iriuchishima, Takanori; Tajima, Goro; Ingham, Sheila J M; Shen, Wei; Horaguchi, Takashi; Saito, Akiyoshi; Smolinski, Patrick; Fu, Freddie H

    2009-06-01

    Anterior cruciate ligament (ACL) graft impingement against the intercondylar roof has been postulated, but not thoroughly investigated. The roof impingement pressure changes with different tibial and femoral tunnel positions in ACL reconstruction. Anterior tibial translation is also affected by the tunnel positions of ACL reconstruction. The study design included a controlled laboratory study. In 15 pig knees, the impingement pressure between ACL and intercondylar roof was measured using pressure sensitive film before and after ACL single bundle reconstruction. ACL reconstructions were performed in each knee with two different tibial and femoral tunnel position combinations: (1) tibial antero-medial (AM) tunnel to femoral AM tunnel (AM to AM) and (2) tibial postero-lateral (PL) tunnel to femoral High-AM tunnel (PL to High-AM). Anterior tibial translation (ATT) was evaluated after each ACL reconstruction using robotic/universal force-moment sensor testing system. Neither the AM to AM nor the PL to High-AM ACL reconstruction groups showed significant difference when compared with intact ACL in roof impingement pressure. The AM to AM group had a significantly higher failure load than PL to High-AM group. This study showed how different tunnel placements affect the ACL-roof impingement pressure and anterior-posterior laxity in ACL reconstruction. Anatomical ACL reconstruction does not cause roof impingement and it has a biomechanical advantage in ATT when compared with non-anatomical ACL reconstructions in the pig knee. There is no intercondylar roof impingement after anatomical single bundle ACL reconstruction.

  14. Installation of a Roof Mounted Photovoltaic System

    NASA Astrophysics Data System (ADS)

    Lam, M.

    2015-12-01

    In order to create a safe and comfortable environment for students to learn, a lot of electricity, which is generated from coal fired power plants, is used. Therefore, ISF Academy, a school in Hong Kong with approximately 1,500 students, will be installing a rooftop photovoltaic (PV) system with 302 solar panels. Not only will these panels be used to power a classroom, they will also serve as an educational opportunity for students to learn about the importance of renewable energy technology and its uses. There were four different options for the installation of the solar panels, and the final choice was made based on the loading capacity of the roof, considering the fact that overstressing the roof could prove to be a safety hazard. Moreover, due to consideration of the risk of typhoons in Hong Kong, the solar panel PV system will include concrete plinths as counterweights - but not so much that the roof would be severely overstressed. During and after the installation of the PV system, students involved would be able to do multiple calculations, such as determining the reduction of the school's carbon footprint. This can allow students to learn about the impact renewable energy can have on the environment. Another project students can participate in includes measuring the efficiency of the solar panels and how much power can be produced per year, which in turn can help with calculate the amount of money saved per year and when we will achieve economic parity. In short, the installation of the roof mounted PV system will not only be able to help save money for the school but also provide learning opportunities for students studying at the ISF Academy.

  15. Building America Case Study: Project Overcoat: Airtightness Strategies and Impacts for 1-1/2 Story Homes, Minneapolis, Minnesota (Fact Sheet)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None, None

    In this second study on solutions to ice dams in 1-1/2 story homes, five test homes located in both cold and very cold climates were analyzed for air leakage reduction rates following modifications by independent contractors on owner-occupied homes. The reason for choosing this house type was they are very common in our area and very difficult to air seal and insulate effectively. Two projects followed a roof-only Exterior Thermal Moisture Management System (ETMMS) process. One project used an interior-only approach to roof air sealing and insulation. The remaining two projects used a deep energy retrofit approach for whole housemore » (foundation wall, above grade wall, roof) air leakage and heat loss reduction. All were asked to provide information regarding project goals, process, and pre and post-blower door test results. Additional air leakage reduction data was provided by several NorthernSTAR Building America industry partners for interior-applied, roof-only modifications on 1-1/2 story homes. The data represents homes in the general market as well as homes that were part of the state of Minnesota weatherization program. A goal was to compare exterior air sealing methods with interior approaches. This pool of data enabled us to compare air tightness data from over 220 homes using similar air seal methods.« less

  16. Experimental evaluation of thermal and energy performance of temperate green roofs: a case study in Beijing

    NASA Astrophysics Data System (ADS)

    Sun, T.; Institute of Hydrology; Water Resources

    2011-12-01

    An experimental evaluation of thermal and energy performance of temperate green roofs was carried out by thermal and meteorological observation and energy budget modeling using a setup of green roof in Beijing urban area. From both the yearly and daily temperature trends, the green roof could effectively damp down the undulation of roof surface temperature comparing with the conventional one. As an insulating screen, the green roof abated the amplitude of temperature by 9.0 in winter and 9.1 °C in summer, respectively. Under different cloud conditions, the green roof in summer time resulted in decreases in sensible heat and heat flux by 125.3W m-2 and 32.0 W m-2, respectively, on daily average comparing with the conventional one. Based on the energy budget analyses, under an assumptive scenario of 50% roof-greening in Beijing, a total of 34.1 PJ of sensible heat and 8.7 PJ of heat flux would be decreased for a summer period of 90 days. This study demonstrated that green roof, serving as an insulating screen to building top in comparison with the conventional roof, proved thermal improving effect in building scale and high energy saving potential for urban development.

  17. 'Passive-roof' duplex geometry in the frontal structures of the Kirthar and Sulaiman mountain belts, Pakistan

    NASA Astrophysics Data System (ADS)

    Banks, C. J.; Warburton, J.

    Exploration for hydrocarbons over the past few years has greatly improved our understanding of the geometry of frontal mountain belt structures. In this study we introduce and discuss the concept of the 'Passive-roof duplex', using as the main example the Kirthar and Sulaiman Ranges in the Baluchistan Province of Pakistan. Structures similar to those described here have been recognized previously in other mountain belts, and they appear to exist as a common feature in many more frontal regions of mountain belts. Our example of a Passive-roof duplex which we describe from Pakistan is compared briefly with similar structures reported by others. The Passive-roof duplex is here defined as a duplex whose roof thrust has backthrust sense ( Passive-roof thrust) and whose roof sequence (those rocks lying above the roof thrust) remains relatively 'stationary' during foreland directed piggy-back style propagation of horses within the duplex.

  18. [Capacity of extensive green roof to retain rainwater runoff in hot and humid region.

    PubMed

    Liu, Ming Xin; Dai, Se Ping; Zhou, Tian Yang; Ruan, Lin; Zhang, Qiao Song

    2017-02-01

    The water logging has become the environmental problem of major cities with the sharp increase of impermeable urban pavement as the contributing cause. Abroad, the green roof has been widely used as a practical measure to intercept rainwater, yet the capacity of green roof to retain rainwater varies with climate conditions. As the hot and humid climate zone features high temperature, humidity and precipitation, it is meaningful to study the capacity of green roof to retain rainwater under such climatic condition. In this research, 3 plat forms were set up in Guangzhou in rainy and hot summer to test the capability of simple green roof to retain rainwater runoff, and the efficiency of green roof to retain rainwater under local climate conditions was worked out based on the meteorological observation and data measurement during the 13-month test period. The results showed that the simple green roof with a substrate thickness of 30, 50 and 70 mm could retain 27.2%, 30.9% and 32.1% of precipitation and reduce the average peak value by 18.9%, 26.2% and 27.7%, respectively. Given an urban built-up area of 1035.01 km 2 in Guangzhou and a roof area percentage of approximately 37.3% and assuming the green roofs with 30 mm-thick substrate were applied within the area, the light, medium and heavy rain could be delayed at 72.8%, 22.6% and 17.4%, respectively. Accordingly, the rainwater retained could reach up to 14317×10 4 m 3 . It suggested the great potential of the simple green roof in retaining rainwater. The research could serve as reference for the hot and humid climate zone to alleviate water logging and visualize sponge city construction.

  19. Solare Cell Roof Tile And Method Of Forming Same

    DOEpatents

    Hanoka, Jack I.; Real, Markus

    1999-11-16

    A solar cell roof tile includes a front support layer, a transparent encapsulant layer, a plurality of interconnected solar cells and a backskin layer. The front support layer is formed of light transmitting material and has first and second surfaces. The transparent encapsulant layer is disposed adjacent the second surface of the front support layer. The interconnected solar cells has a first surface disposed adjacent the transparent encapsulant layer. The backskin layer has a first surface disposed adjacent a second surface of the interconnected solar cells, wherein a portion of the backskin layer wraps around and contacts the first surface of the front support layer to form the border region. A portion of the border region has an extended width. The solar cell roof tile may have stand-offs disposed on the extended width border region for providing vertical spacing with respect to an adjacent solar cell roof tile.

  20. Analysis of materials used for Greenhouse roof covering - structure using CFD

    NASA Astrophysics Data System (ADS)

    Subin, M. C.; Savio Lourence, Jason; Karthikeyan, Ram; Periasamy, C.

    2018-04-01

    Greenhouse is widely used to create a suitable environment for the growth of plant. During summer, high temperatures cause harm to the plant. This work calculates characteristics required to optimize the above-mentioned parameters using different roof structure covering materials for the greenhouse. Moreover, this work also presents a simulation of the cooling and heating system. In addition, a computer model based on Ansys Fluent has been using to predict the temperature profiles inside the greenhouse. Greenhouse roof structure shading may have a time-dependent effect the production, water and nutrient uptake in plants. An experiment was conducted in the emirate of Dubai in United Arab Emirates to discover the impact of different materials in order to have an optimal plant growth zone and yield production. These structures were poly ethylene and poly carbonate sheets of 2 different configurations. Results showed that poly carbonate sheets configuration of optimal thickness has given a high result in terms of yield production. Therefore, there is a need for appropriate material selection of greenhouse roof structure in this area of UAE. Major parameters and properties need to be considered while selecting a greenhouse roof structure are the resistance to solar radiation, weathering, thermal as well as mechanical properties and good abrasion resistance. In the present study, an experiment has been conducted to find out the material suitability of the greenhouse roof structure in terms of developing proper ambient conditions especially to minimize the energy lose by reducing the HVAC and lighting expenses. The configuration verified using the CFD, so it has been concluded that polycarbonate can be safely used in the greenhouse than other roof structure material having white or green colour.

  1. Revisiting the Climate Impacts of Cool Roofs around the Globe Using an Earth System Model

    NASA Astrophysics Data System (ADS)

    Zhang, J.; Ban-Weiss, G. A.; Zhang, K.; Liu, J.

    2016-12-01

    Solar reflective "cool roofs" absorb less sunlight than traditional dark roofs, reducing solar heat gain, and decreasing the amount of heat transferred to the atmosphere. Widespread adoption of cool roofs could therefore reduce temperatures in urban areas, partially mitigating the urban heat island effect, and contributing to reversing the local impacts of global climate change. The impacts of cool roofs on global climate remain debated by past research and are uncertain. Using a sophisticated Earth system model, the impacts of cool roofs on climate are investigated at urban, continental, and global scales. We find that global adoption of cool roofs in urban areas reduces urban heat islands everywhere, with an annual- and global-mean decrease from 1.6 to 1.2 K. Decreases are statistically significant, except for some areas in Africa and Mexico where urban fraction is low, and some high-latitude areas during wintertime. Analysis of the surface and TOA energy budget in urban regions at continental-scale shows cool roofs causing increases in solar radiation leaving the Earth-atmosphere system in most regions around the globe, though the presence of aerosols and clouds are found to partially offset increases in upward radiation. Aerosols dampen cool roof-induced increases in upward solar radiation, ranging from 4% in the United States to 18% in more polluted China. Adoption of cool roofs also causes statistically significant reductions in surface air temperatures in urbanized regions of China (-0.11±0.10 K) and the United States (-0.14±0.12 K); India and Europe show statistically insignificant changes. Though past research has disagreed on whether widespread adoption of cool roofs would cool or warm global climate, these studies have lacked analysis on the statistical significance of global temperature changes. The research presented here indicates that adoption of cool roofs around the globe would lead to statistically insignificant reductions in global mean air

  2. Quality and seasonal variation of rainwater harvested from concrete, asphalt, ceramic tile and green roofs in Chongqing, China.

    PubMed

    Zhang, Qianqian; Wang, Xiaoke; Hou, Peiqiang; Wan, Wuxing; Li, Ruida; Ren, Yufen; Ouyang, Zhiyun

    2014-01-01

    There is an urgent requirement to examine the quality of harvested rainwater for potable and non-potable purposes, based on the type of roofing material. In this study, we examined the effect on the quality of harvested rainwater of conventional roofing materials (concrete, asphalt and ceramic tile roofs) compared with alternative roofing materials (green roof). The results showed that the ceramic tile roof was the most suitable for rainwater-harvesting applications because of the lower concentrations of leachable pollutants. However, in this study, the green roof was not suitable for rainwater harvesting applications. In addition, seasonal trends in water quality parameters showed that pollutants in roof runoff in summer and autumn were lower than those in winter and spring. This study revealed that the quality of harvested rainwater was significantly affected by the roofing material; therefore, local government and urban planners should develop stricter testing programs and produce more weathering resistant roofing materials to allow the harvesting of rainwater for domestic and public uses. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Numerical analysis of pressure field on curved self-weighted metallic roofs due to the wind effect by the finite element method

    NASA Astrophysics Data System (ADS)

    Del Coz Diaz, J. J.; Garcia Nieto, P. J.; Suarez Dominguez, F. J.

    2006-07-01

    In this paper, an evaluation of distribution of the air pressure is determined throughout the curved and open self-weighted metallic roof due to the wind effect by the finite element method (FEM) [K. Bathe, Finite Element Procedures, Prentice-Hall, Englewood Cliffs, New York, 1996]. Data from experimental tests carried out in a wind tunnel involving a reduced scale model of a roof was used for comparison. The nonlinearity is due to time-averaged Navier-Stokes equations [C.A.J. Fletcher, Computational Techniques for Fluid Dynamics, Springer, Berlin, 1991] that govern the turbulent flow. The calculation has been carried out keeping in mind the possibility of turbulent flow in the vicinities of the walls, and speeds of wind have been analyzed between 30 and 40 m/s. Finally, the forces and moments are determined on the cover, as well as the distribution of pressures on the same one, comparing the results obtained with the Spanish and European Standards rules, giving place to the conclusions that are exposed in the study.

  4. Assessing the Performance of Large Scale Green Roofs and Their Impact on the Urban Microclimate

    NASA Astrophysics Data System (ADS)

    Smalls-Mantey, L.; Foti, R.; Montalto, F. A.

    2015-12-01

    In ultra-urban environments green roofs offer a feasible solution to add green infrastructure (GI) in neighborhoods where space is limited. Green roofs offer the typical advantages of urban GI such as stormwater reduction and management while providing direct benefits to the buildings on which they are installed through thermal protection and mitigation of temperature fluctuations. At 6.8 acres, the Jacob K. Javits Convention Center (JJCC) in New York City, hosts the second largest green roof in the United States. Since its installation in August 2013, the Sustainable Water Resource (SWRE) Laboratory at Drexel University has monitored the climate on and around the green roof by means of four weather stations situated on various roof and ground locations. Using two years of fine scale climatic data collected at the JJCC, this study explores the energy balance of a large scale green roof system. Temperature, radiation, evapotranspiration and wind profiles pre- and post- installation of the JJCC green roof were analyzed and compared across monitored locations, with the goal of identifying the impact of the green roof on the building and urban micro-climate. Our findings indicate that the presence of the green roof, not only altered the climatic conditions above the JJCC, but also had a measurable impact on the climatic profile of the areas immediately surrounding it. Furthermore, as a result of the mitigation of roof temperature fluctuations and of the cooling provided during warmer months, an improvement of the building thermal efficiency was contextually observed. Such findings support the installation of GI as an effective practice in urban settings and important in the discussion of key issues including energy conservation measures, carbon emission reductions and the mitigation of urban heat islands.

  5. Cool Roofs Through Time and Space

    ScienceCinema

    Levinson, Ronnen

    2018-01-16

    Ronnen Levinson, from the Lab's Heat Island Group, presents his research on cool roofs and introduces the California Cities Albedo Map at our '8 Big Ideas' Science at the Theater event on October 8th, 2014, in Oakland, California.

  6. Cool Roofs Through Time and Space

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Levinson, Ronnen

    2014-10-17

    Ronnen Levinson, from the Lab's Heat Island Group, presents his research on cool roofs and introduces the California Cities Albedo Map at our '8 Big Ideas' Science at the Theater event on October 8th, 2014, in Oakland, California.

  7. 112. ARAI Hot cell (ARA626) Building roof plan and details ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    112. ARA-I Hot cell (ARA-626) Building roof plan and details of roof ventilating equipment and parapet. Norman Engineering Company: 961-area/SF-626-A-2. Date: January 1959. Ineel index code no. 068-0626-00-613-102722. - Idaho National Engineering Laboratory, Army Reactors Experimental Area, Scoville, Butte County, ID

  8. COOL ROOF COATINGS INCORPORATING GLASS HOLLOW MICROSPHERES FOR IMPROVED SOLAR REFLECTANCE

    EPA Science Inventory

    Elastomeric cool-roof coatings can be applied to buildings to decrease heat gain, yielding energy savings and mitigating the “urban heat island” effect. Most cool-roof formulations are based on titanium dioxide (TiO2). While TiO2 and several TiO2

  9. 40 CFR Table 2 of Subpart Aaaaaaa... - Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 14 2011-07-01 2011-07-01 false Emission Limits for Asphalt Roofing... Pollutants for Area Sources: Asphalt Processing and Asphalt Roofing Manufacturing Other Requirements and... AAAAAAA of Part 63—Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations For * * * 1...

  10. 40 CFR Table 2 of Subpart Aaaaaaa... - Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 15 2013-07-01 2013-07-01 false Emission Limits for Asphalt Roofing... Pollutants for Area Sources: Asphalt Processing and Asphalt Roofing Manufacturing Other Requirements and... AAAAAAA of Part 63—Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations For * * * 1...

  11. 40 CFR Table 2 of Subpart Aaaaaaa... - Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 15 2014-07-01 2014-07-01 false Emission Limits for Asphalt Roofing... Pollutants for Area Sources: Asphalt Processing and Asphalt Roofing Manufacturing Other Requirements and... AAAAAAA of Part 63—Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations For * * * 1...

  12. 40 CFR Table 2 of Subpart Aaaaaaa... - Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 15 2012-07-01 2012-07-01 false Emission Limits for Asphalt Roofing... Pollutants for Area Sources: Asphalt Processing and Asphalt Roofing Manufacturing Other Requirements and... AAAAAAA of Part 63—Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations For * * * 1...

  13. 75 FR 7029 - Notice of Availability of the Final Environmental Assessment for Solar Roof Project

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-16

    ... Assessment for Solar Roof Project AGENCY: United States Geological Survey. ACTION: Notice of availability... Final Environmental Assessment for the Solar Roof Project and by this notice is announcing its... Individuals wishing to receive copies of the Environmental Assessment for the Solar Roof Project should...

  14. Extensive Green Roof Species and Soilless Media Evaluations in Semi-arid Colorado

    EPA Science Inventory

    In the high elevation, semi-arid climate of Colorado, green roofs have not been scientifically tested. This research examined alternative plant species, soilless media blends and plant interactions on an existing, modular-extensive (shallow, 10 cm deep) green roof in Denver, Colo...

  15. View of McKenzieRichey barn showing shed design, rolled roofing and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of McKenzie-Richey barn showing shed design, rolled roofing and wood shed roof, facing southwest - McKenzie Property, Barn, North Bank of Sailor Gulch, 750 feet northwest of intersection of U.S.F.S. Roads 651 & 349, Placerville, Boise County, ID

  16. Roof plan, Combat Operations Center, Building No. 2605. (Also includes ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Roof plan, Combat Operations Center, Building No. 2605. (Also includes a typical roof section, with new fiberglass and urethane insulation layers.) By Federal Builders, 575 Carreon Drive, Colton, California. Sheet 1 of 1, dated 18 May 1992. Scale one-eighth inch to one foot. 24x36 inches. ink on paper - March Air Force Base, Strategic Air Command, Combat Operations Center, 5220 Riverside Drive, Moreno Valley, Riverside County, CA

  17. Simulation study on electric field intensity above train roof

    NASA Astrophysics Data System (ADS)

    Fan, Yizhe; Li, Huawei; Yang, Shasha

    2018-04-01

    In order to understand the distribution of electric field in the space above the train roof accurately and select the installation position of the detection device reasonably, in this paper, the 3D model of pantograph-catenary is established by using SolidWorks software, and the spatial electric field distribution of pantograph-catenary model is simulated based on Comsol software. According to the electric field intensity analysis within the 0.4m space above train roof, we give a reasonable installation of the detection device.

  18. Development of a green roof environmental monitoring and meteorological network in new york city.

    PubMed

    Gaffin, Stuart R; Khanbilvardi, Reza; Rosenzweig, Cynthia

    2009-01-01

    Green roofs (with plant cover) are gaining attention in the United States as a versatile new environmental mitigation technology. Interest in data on the environmental performance of these systems is growing, particularly with respect to urban heat island mitigation and stormwater runoff control. We are deploying research stations on a diverse array of green roofs within the New York City area, affording a new opportunity to monitor urban environmental conditions at small scales. We show some green roof systems being monitored, describe the sensor selection employed to study energy balance, and show samples of selected data. These roofs should be superior to other urban rooftops as sites for meteorological stations.

  19. Investigation of the proposed solar-driven moisture phenomenon in asphalt shingle roofs

    DOE PAGES

    Boudreaux, Philip; Pallin, Simon; Jackson, Roderick

    2016-01-19

    We report that unvented, sealed or conditioned attics are an energy efficiency measure to reduce the thermal load of the home and decrease the space conditioning energy consumption. This retrofit is usually done by using spray polyurethane foam underneath the roof sheathing and on the gables and soffits of an attic to provide a thermal and air barrier. Unvented attics perform well from this perspective but from a moisture perspective sometimes the unvented attic homes have high interior humidity or moisture damage to the roof. As homes become more air tight and energy efficient, an understanding of the hygrothermal dynamicsmore » of the home become more important. One proposed reason for high unvented attic humidity has been that moisture can come through the asphalt shingle roof system and increase the moisture content of the roof sheathing and attic air. This has been called solar driven moisture. Oak Ridge National Laboratory (ORNL) investigated this proposed phenomenon by examining the physical properties of a roof and the physics required for the phenomenon. Results showed that there are not favorable conditions for solar driven moisture to occur. ORNL also conducted an experimental study on an unvented attic home and compared the humidity below the roof sheathing before and after a vapor impermeable underlayment was installed. There was no statistically significant difference in absolute humidity before and after the vapor barrier was installed. Finally, the outcome of the theoretical and experimental study both suggest that solar driven moisture does not occur in any significant amount.« less

  20. 40 CFR Table 2 of Subpart Aaaaaaa... - Emission Limits for Asphalt Roofing Manufacturing (Coating) Operations

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    .... Coater-only production lines a. Limit PAH emissions to 0.0002 lb/ton of asphalt roofing product...-only production lines a. Limit PAH emissions to 0.0007 lb/ton of asphalt roofing product manufactured... saturator/coater production lines a. Limit PAH emissions to 0.0009 lb/ton of asphalt roofing product...

  1. Technology Solutions Case Study: Excavationless: Exterior-Side Foundation Insulation for Existing Homes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    Building science research supports installing exterior (soil side) foundation insulation as the optimal method to enhance the hygrothermal performance of new homes. With exterior foundation insulation, water management strategies are maximized while insulating the basement space and ensuring a more even temperature at the foundation wall. This project describes an innovative, minimally invasive foundation insulation upgrade technique on an existing home that uses hydrovac excavation technology combined with a liquid insulating foam. Cost savings over the traditional excavation process ranged from 23% to 50%. The excavationless process could result in even greater savings since replacement of building structures, exterior features,more » utility meters, and landscaping would be minimal or non-existent in an excavationless process.« less

  2. Revisiting the climate impacts of cool roofs around the globe using an Earth system model

    NASA Astrophysics Data System (ADS)

    Zhang, Jiachen; Zhang, Kai; Liu, Junfeng; Ban-Weiss, George

    2016-08-01

    Solar reflective ‘cool roofs’ absorb less sunlight than traditional dark roofs, reducing solar heat gain, and decreasing the amount of heat transferred to the atmosphere. Widespread adoption of cool roofs could therefore reduce temperatures in urban areas, partially mitigating the urban heat island effect, and contributing to reversing the local impacts of global climate change. The impacts of cool roofs on global climate remain debated by past research and are uncertain. Using a sophisticated Earth system model, the impacts of cool roofs on climate are investigated at urban, continental, and global scales. We find that global adoption of cool roofs in urban areas reduces urban heat islands everywhere, with an annual- and global-mean decrease from 1.6 to 1.2 K. Decreases are statistically significant, except for some areas in Africa and Mexico where urban fraction is low, and some high-latitude areas during wintertime. Analysis of the surface and TOA energy budget in urban regions at continental-scale shows cool roofs causing increases in solar radiation leaving the Earth-atmosphere system in most regions around the globe, though the presence of aerosols and clouds are found to partially offset increases in upward radiation. Aerosols dampen cool roof-induced increases in upward solar radiation, ranging from 4% in the United States to 18% in more polluted China. Adoption of cool roofs also causes statistically significant reductions in surface air temperatures in urbanized regions of China (-0.11 ± 0.10 K) and the United States (-0.14 ± 0.12 K); India and Europe show statistically insignificant changes. Though past research has disagreed on whether widespread adoption of cool roofs would cool or warm global climate, these studies have lacked analysis on the statistical significance of global temperature changes. The research presented here indicates that adoption of cool roofs around the globe would lead to statistically insignificant reductions in global mean

  3. THE VALUE OF STEEP, GREEN ROOF TECHNOLOGY TO SUSTAINABLE COLD CLIMATE COMMUNITIES

    EPA Science Inventory

    With the knowledge gained from this preliminary study, we plan to built a modified extensive green roof product that addresses both the opportunities and limitations of current extensive manufactured green roof products. The results of our tests will be shared with building c...

  4. REGIONALLY APPROPRIATE SUSTAINABLE DESIGN: URBAN GREEN ROOF APPLICATIONS FOR TEMPERATE CONTINENTAL CLIMATES

    EPA Science Inventory

    As a strategy for sustainable development, green roof technology is gaining acceptance in the U.S. However, widespread adoption in highly variable continental climates, such as the Upper Midwest (EPA Region 5), lags behind green roof use in cities with simi...

  5. 49 CFR 238.123 - Emergency roof access.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... access location shall be conspicuously marked with retroreflective material of contrasting color. As... material shall conspicuously mark the line along which the roof skin shall be cut; and (2) A sign plate...

  6. Airborne Exposures to Polycyclic Aromatic Compounds Among Workers in Asphalt Roofing Manufacturing Facilities.

    PubMed

    Trumbore, David C; Osborn, Linda V; Johnson, Kathleen A; Fayerweather, William E

    2015-01-01

    We studied exposure of 151 workers to polycyclic aromatic compounds and asphalt emissions during the manufacturing of asphalt roofing products-including 64 workers from 10 asphalt plants producing oxidized, straight-run, cutback, and wax- or polymer-modified asphalts, and 87 workers from 11 roofing plants producing asphalt shingles and granulated roll roofing. The facilities were located throughout the United States and used asphalt from many refiners and crude oils. This article helps fill a gap in exposure data for asphalt roofing manufacturing workers by using a fluorescence technique that targets biologically active 4-6 ring polycyclic aromatic compounds and is strongly correlated with carcinogenic activity in animal studies. Worker exposures to polycyclic aromatic compounds were compared between manufacturing plants, at different temperatures and using different raw materials, and to important external benchmarks. High levels of fine limestone particulate in the plant air during roofing manufacturing increased polycyclic aromatic compound exposure, resulting in the hypothesis that the particulate brought adsorbed polycyclic aromatic compounds to the worker breathing zone. Elevated asphalt temperatures increased exposures during the pouring of asphalt. Co-exposures in these workplaces which act as confounders for both the measurement of total organic matter and fluorescence were detected and their influence discussed. Exposures to polycyclic aromatic compounds in asphalt roofing manufacturing facilities were lower than or similar to those reported in hot-mix paving application studies, and much below those reported in studies of hot application of built-up roofing asphalt. These relatively low exposures in manufacturing are primarily attributed to air emission controls in the facilities, and the relatively moderate temperatures, compared to built-up roofing, used in these facilities for oxidized asphalt. The exposure to polycyclic aromatic compounds was a very

  7. A Fiber Bragg Grating-Based Monitoring System for Roof Safety Control in Underground Coal Mining

    PubMed Central

    Zhao, Yiming; Zhang, Nong; Si, Guangyao

    2016-01-01

    Monitoring of roof activity is a primary measure adopted in the prevention of roof collapse accidents and functions to optimize and support the design of roadways in underground coalmines. However, traditional monitoring measures, such as using mechanical extensometers or electronic gauges, either require arduous underground labor or cannot function properly in the harsh underground environment. Therefore, in this paper, in order to break through this technological barrier, a novel monitoring system for roof safety control in underground coal mining, using fiber Bragg grating (FBG) material as a perceived element and transmission medium, has been developed. Compared with traditional monitoring equipment, the developed, novel monitoring system has the advantages of providing accurate, reliable, and continuous online monitoring of roof activities in underground coal mining. This is expected to further enable the prevention of catastrophic roof collapse accidents. The system has been successfully implemented at a deep hazardous roadway in Zhuji Coal Mine, China. Monitoring results from the study site have demonstrated the advantages of FBG-based sensors over traditional monitoring approaches. The dynamic impacts of progressive face advance on roof displacement and stress have been accurately captured by the novel roadway roof activity and safety monitoring system, which provided essential references for roadway support and design of the mine. PMID:27775657

  8. Turbulence and Air Exchange in a Two-Dimensional Urban Street Canyon Between Gable Roof Buildings

    NASA Astrophysics Data System (ADS)

    Garau, Michela; Badas, Maria Grazia; Ferrari, Simone; Seoni, Alessandro; Querzoli, Giorgio

    2018-04-01

    We experimentally investigate the effect of a typical building covering: the gable roof, on the flow and air exchange in urban canyons. In general, the morphology of the urban canopy is very varied and complex, depending on a large number of factors, such as building arrangement, or the morphology of the terrain. Therefore we focus on a simple, prototypal shape, the two-dimensional canyon, with the aim of elucidating some fundamental phenomena driving the street-canyon ventilation. Experiments are performed in a water channel, over an array of identical prismatic obstacles representing an idealized urban canopy. The aspect ratio, i.e. canyon-width to building-height ratio, ranges from 1 to 6. Gable roof buildings with 1:1 pitch are compared with flat roofed buildings. Velocity is measured using a particle-image-velocimetry technique with flow dynamics discussed in terms of mean flow and second- and third-order statistical moments of the velocity. The ventilation is interpreted by means of a simple well-mixed box model and the outflow rate and mean residence time are computed. Results show that gable roofs tend to delay the transition from the skimming-flow to the wake-interference regime and promote the development of a deeper and more turbulent roughness layer. The presence of a gable roof significantly increases the momentum flux, especially for high packing density. The air exchange is improved compared to the flat roof buildings, and the beneficial effect is more significant for narrow canyons. Accordingly, for unit aspect ratio gable roofs reduce the mean residence time by a factor of 0.37 compared to flat roofs, whereas the decrease is only by a factor of 0.9 at the largest aspect ratio. Data analysis indicates that, for flat roof buildings, the mean residence time increases by 30% when the aspect ratio is decreased from 6 to 2, whereas this parameter is only weakly dependent on aspect ratio in the case of gable roofs.

  9. Estimation of Solar Radiation on Building Roofs in Mountainous Areas

    NASA Astrophysics Data System (ADS)

    Agugiaro, G.; Remondino, F.; Stevanato, G.; De Filippi, R.; Furlanello, C.

    2011-04-01

    The aim of this study is estimating solar radiation on building roofs in complex mountain landscape areas. A multi-scale solar radiation estimation methodology is proposed that combines 3D data ranging from regional scale to the architectural one. Both the terrain and the nearby building shadowing effects are considered. The approach is modular and several alternative roof models, obtained by surveying and modelling techniques at varying level of detail, can be embedded in a DTM, e.g. that of an Alpine valley surrounded by mountains. The solar radiation maps obtained from raster models at different resolutions are compared and evaluated in order to obtain information regarding the benefits and disadvantages tied to each roof modelling approach. The solar radiation estimation is performed within the open-source GRASS GIS environment using r.sun and its ancillary modules.

  10. Portulaca grandiflora as green roof vegetation: Plant growth and phytoremediation experiments.

    PubMed

    Vijayaraghavan, K; Arockiaraj, Jesu; Kamala-Kannan, Seralathan

    2017-06-03

    Finding appropriate rooftop vegetation may improve the quality of runoff from green roofs. Portulaca grandiflora was examined as possible vegetation for green roofs. Green roof substrate was found to have low bulk density (360.7 kg/m 3 ) and high water-holding capacity (49.4%), air-filled porosity (21.1%), and hydraulic conductivity (5270 mm/hour). The optimal substrate also supported the growth of P. grandiflora with biomass multiplication of 450.3% and relative growth rate of 0.038. Phytoextraction potential of P. grandiflora was evaluated using metal-spiked green roof substrate as a function of time and spiked substrate metal concentration. It was identified that P. grandiflora accumulated all metals (Al, Cd, Cr, Cu, Fe, Ni, Pb, and Zn) from metal-spiked green roof substrate. At the end of 40 days, P. grandiflora accumulated 811 ± 26.7, 87.2 ± 3.59, 416 ± 15.8, 459 ± 15.6, 746 ± 20.9, 357 ± 18.5, 565 ± 6.8, and 596 ± 24.4 mg/kg of Al, Cd, Cr, Cu, Fe, Ni, Pb and Zn, respectively. Results also indicated that spiked substrate metal concentration strongly influenced metal accumulation property of P. grandiflora with metal uptake increased and accumulation factor decreased with increase in substrate metal concentration. P. grandiflora also showed potential to translocate all the examined metals with translocation factor greater than 1 for Al, Cu, Fe, and Zn, indicating hyperaccumulation property.

  11. Compressive behavior of energy-saving fired facing brick composite wall

    NASA Astrophysics Data System (ADS)

    Guo, Kai; Wu, Cai

    2018-03-01

    The energy-saving fired facing brick composite wall has a broad development prospects due to its merits of thermal insulation, energy conservation, beautiful, and natural. The construction and characteristics of this wall are introduced and analyzed in this paper. Experimental studies of samples are also conducted to investigate its compressive performance. The results show that the energy-saving fired facing brick composite wall has high compressive capacity. It has considerable application prospect, the study in this paper provides foundation to further studies.

  12. Lead theft--a study of the "uniqueness" of lead from church roofs.

    PubMed

    Bond, John W; Hainsworth, Sarah V; Lau, Tien L

    2013-07-01

    In the United Kingdom, theft of lead is common, particularly from churches and other public buildings with lead roofs. To assess the potential to distinguish lead from different sources, 41 samples of lead from 24 church roofs in Northamptonshire, U.K, have been analyzed for relative abundance of trace elements and isotopes of lead using X-ray fluorescence (XRF) and inductively coupled plasma mass spectrometry, respectively. XRF revealed the overall presence of 12 trace elements with the four most abundant, calcium, phosphorus, silicon, and sulfur, showing a large weight percentage standard error of the mean of all samples suggesting variation in the weight percentage of these elements between different church roofs. Multiple samples from the same roofs, but different lead sheets, showed much lower weight percentage standard errors of the mean suggesting similar trace element concentrations. Lead isotope ratios were similar for all samples. Factors likely to affect the occurrence of these trace elements are discussed. © 2013 American Academy of Forensic Sciences.

  13. Water quality and quantity investigation of green roofs in a dry climate.

    PubMed

    Beecham, S; Razzaghmanesh, M

    2015-03-01

    Low-energy pollutant removal strategies are now being sought for water sensitive urban design. This paper describes investigations into the water quality and quantity of sixteen, low-maintenance and unfertilized intensive and extensive green roof beds. The factors of Slope (1° and 25°), Depth (100 mm and 300 mm), Growing media (type A, type B and type C) and Species (P1, P2 and P3) were randomized according to a split-split plot design. This consisted of twelve vegetated green roof beds and four non-vegetated beds as controls. Stormwater runoff was collected from drainage points that were installed in each area. Samples of run-off were collected for five rainfall events and analysed for water retention capacity and the water quality parameters of NO₂, NO₃, NH₄, PO₄, pH, EC, TDS, Turbidity, Na, Ca, Mg and K. The results indicated significant differences in terms of stormwater water quality and quantity between the outflows of vegetated and non-vegetated systems. The water retention was between 51% and 96% and this range was attributed to the green roof configurations in the experiment. Comparing the quality of rainfall as inflow, and the quality of runoff from the systems showed that green roofs generally acted as a source of pollutants in this study. In the vegetated beds, the intensive green roofs performed better than the extensive beds with regard to outflow quality while in the non-vegetated beds, the extensive beds performed better than intensive systems. This highlights the importance of vegetation in improving water retention capacity as well as the role of vegetation in enhancing pollutant removal in green roof systems. In addition growing media with less organic matter had better water quality performance. Comparison of these results with national and international standards for water reuse confirmed that the green roof outflow was suitable for non-potable uses such as landscape irrigation and toilet flushing. Copyright © 2014 Elsevier Ltd. All

  14. Test and evaluation of the attic temperature reduction potential of plastic roof shakes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Holton, J.K.; Beggs, T.R.

    1999-07-01

    While monitoring the comparative performance of two test houses in Pittsburgh, Pennsylvania, it was noticed that the attic air temperature of one house with a plastic shake roof was consistently 20 F (11 C) cooler than its twin with asphalt shingles during peak summer cooling periods. More detailed monitoring of the temperatures on the plastic shake, the roof deck, and the attic showed this effect to be largely due to the plastic shake and not to better roof venting or other heat loss mechanisms.

  15. Development of a Green Roof Environmental Monitoring and Meteorological Network in New York City

    PubMed Central

    Gaffin, Stuart R.; Khanbilvardi, Reza; Rosenzweig, Cynthia

    2009-01-01

    Green roofs (with plant cover) are gaining attention in the United States as a versatile new environmental mitigation technology. Interest in data on the environmental performance of these systems is growing, particularly with respect to urban heat island mitigation and stormwater runoff control. We are deploying research stations on a diverse array of green roofs within the New York City area, affording a new opportunity to monitor urban environmental conditions at small scales. We show some green roof systems being monitored, describe the sensor selection employed to study energy balance, and show samples of selected data. These roofs should be superior to other urban rooftops as sites for meteorological stations. PMID:22574037

  16. Roofing with Urethane: Pro and Con.

    ERIC Educational Resources Information Center

    Kinzer, Michael; Scott, Gerald P.E.

    1981-01-01

    Gerald Scott's favorable evaluation of the foamed polyurethane roofing system is based on experiences with 55 buildings at Texas A & M. Michael Kinzer, an architect at Colorado State University, disagrees and claims that the system is difficult to install and maintain, and the cost prohibitive. (MLF)

  17. Roof temperatures in simulated attics

    Treesearch

    J. E. Winandy; R. Beaumont

    The degradation of wood treated with fire retardant (FR) chemicals in roof systems is a problem of major national significance. Understanding of this phenomenon is limited by lack of information on how the performance of FR-treated wood in the laboratory correlates to that of FR-treated wood in the field. In this study, five outdoor field exposure chambers were...

  18. Modeling Košice Green Roofs Maps

    NASA Astrophysics Data System (ADS)

    Poorova, Zuzana; Vranayova, Zuzana

    2017-06-01

    The need to house population in urban areas is expected to rise to 66% in 2050, according to United Nations. The replacement of natural permeable green areas with concrete constructions and hard surfaces will be noticed. The densification of existing built-up areas is responsible for the decreasing vegetation, which results in the lack of evapotranspiration cooling the air. Such decreasing vegetation causes urban heat islands. Since roofs and pavements have a very low albedo, they absorb a lot of sunlight. Several studies have shown that natural and permeable surfaces, as in the case of green roofs, can play crucial role in mitigating this negative climate phenomenon and providing higher efficiency for the building, leading to savings. Such as water saving, what is the main idea of this research.

  19. Evaluation of green roof as green technology for urban stormwater quantity and quality controls

    NASA Astrophysics Data System (ADS)

    Kok, K. H.; Sidek, L. M.; Abidin, M. R. Z.; Basri, H.; Muda, Z. C.; Beddu, S.

    2013-06-01

    Promoting green design, construction, reconstruction and operation of buildings has never been more critical than now due to the ever increasing greenhouse gas emissions and rapid urbanizations that are fuelling climate change more quickly. Driven by environmental needs, Green Building Index (GBI) was founded in Malaysia to drive initiative to lead the property industry towards becoming more environment-friendly. Green roof system is one of the assessment criteria of this rating system which is under category of sustainable site planning and management. An extensive green roof was constructed in Humid Tropics Center (HTC) Kuala Lumpur as one of the components for Stormwater Management Ecohydrology (SME) in order to obtain scientific data of the system. This paper evaluates the performance of extensive green roof at Humid Tropics Center with respect to urban heat island mitigation and stormwater quantity and quality controls. Findings indicate that there was a reduction of around 1.5°C for indoor temperature of the building after installation of green roof. Simulations showed that the peak discharge was reduced up to 24% relative to impervious brown roof. The results show an increment of pH and high concentration of phosphate for the runoff generated from the green roof and the runoff water quality ranged between class I and II under INWQS.

  20. Impact Study of Metal Fasteners in Roofing Assemblies using Three-Dimensional Heat Transfer Analysis

    DOE PAGES

    Singh, Manan; Gulati, Rupesh; Ravi, Srinivasan; ...

    2016-11-29

    Heat transfer analysis was performed on typical roofing assemblies using HEAT3, a three-dimensional heat transfer analysis software. The difference in heat transferred through the roofing assemblies considered is compared between two cases - without any steel fasteners and with steel fasteners. In the latter case, the metal roofing fasteners were arranged as per Factor Mutual Global (FMG) approvals, in the field, perimeter, and corner zones of the roof. The temperature conditions used for the analysis represented summer and winter conditions for three separate Climate Zones (CZ) namely Climate Zone 2 or CZ2 represented by Orlando, FL; CZ3 represented by Atlanta,more » GA; and CZ6 zone represented by St. Paul, MN. In all the climatic conditions, higher energy transfer was observed with increase in the number of metal fasteners attributed to high thermal conductivity of metals as compared to the insulation and other materials used in the roofing assembly. This difference in heat loss was also quantified in the form of percentage change in the overall or effective insulation of the roofing assembly for better understanding of the practical aspects. Besides, a comparison of 2D heat transfer analysis (using THERM software) and 3D analysis using HEAT3 is also discussed.« less

  1. Impact Study of Metal Fasteners in Roofing Assemblies using Three-Dimensional Heat Transfer Analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Singh, Manan; Gulati, Rupesh; Ravi, Srinivasan

    Heat transfer analysis was performed on typical roofing assemblies using HEAT3, a three-dimensional heat transfer analysis software. The difference in heat transferred through the roofing assemblies considered is compared between two cases - without any steel fasteners and with steel fasteners. In the latter case, the metal roofing fasteners were arranged as per Factor Mutual Global (FMG) approvals, in the field, perimeter, and corner zones of the roof. The temperature conditions used for the analysis represented summer and winter conditions for three separate Climate Zones (CZ) namely Climate Zone 2 or CZ2 represented by Orlando, FL; CZ3 represented by Atlanta,more » GA; and CZ6 zone represented by St. Paul, MN. In all the climatic conditions, higher energy transfer was observed with increase in the number of metal fasteners attributed to high thermal conductivity of metals as compared to the insulation and other materials used in the roofing assembly. This difference in heat loss was also quantified in the form of percentage change in the overall or effective insulation of the roofing assembly for better understanding of the practical aspects. Besides, a comparison of 2D heat transfer analysis (using THERM software) and 3D analysis using HEAT3 is also discussed.« less

  2. Application of Spray Foam Insulation Under Plywood and OSB Roof Sheathing (Fact Sheet)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None, None

    2013-11-01

    Spray polyurethane foams (SPFs) have advantages over alternative insulation methods because they provide air sealing in complex assemblies, particularly roofs. Spray foam can provide the thermal, air, and vapor control layers in both new and retrofit construction. Unvented roof strategies with open cell and closed cell SPF insulation sprayed to the underside of roof sheathing have been used since the mid-1990s to provide durable and efficient building enclosures. However, there have been isolated incidents of failures (either sheathing rot or SPF delamination) that raise some general concerns about the hygrothermal performance and durability of these systems. The primary risks formore » roof systems are rainwater leaks, condensation from diffusion and air leakage, and built-in construction moisture. This project directly investigated rain and indirectly investigated built-in construction moisture and vapor drives. Research involved both hygrothermal modeling of a range of rain water leakage scenarios and field evaluations of in-service residential roofs. Other variables considered were climate zone, orientation, interior relative humidity, and the vapor permeance of the coating applied to the interior face of open cell SPF.« less

  3. Building Integrated Photovoltaic (BIPV) Roofs for Sustainability and Energy Efficiency

    DTIC Science & Technology

    2013-09-10

    roofs that utilize a-Si PV modules, like the ones in this study , experienced a significantly lower price reduction, which makes them less cost...facility did not matter, a roof in need of replacement was a better use of the funds. As for Site III, since one of the objectives was to study the...at Site II (NAS Patuxent River) and Site III (MCAS Yuma). Equipment regarding the study of the load on the HVAC system, including measuring the

  4. 42. GARRET, SOUTHWEST CORNER. The roof rafters have been notched ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    42. GARRET, SOUTHWEST CORNER. The roof rafters have been notched for shingle lath. In some places the notches and lath do not align. Attached to each joist are furring strips for the 1812 ceiling, allowing it to be lowered about one inch below the under surfaces of the joists. Note that the 1851 shingles were left in place when the 1873-74 tin roof was added. - Twelfth Street Meeting House, 20 South Twelfth Street, Philadelphia, Philadelphia County, PA

  5. MC Contracting, Paint, & Roofing, LLC Information Sheet

    EPA Pesticide Factsheets

    MC Contracting, Paint, & Roofing, LLC, d/b/a M.C. Painting & Contractor and M.C. Painting Group (the Company) is located in Philadelphia, Pennsylvania. The settlement involves renovation activities conducted at property constructed prior to 1978.

  6. PERFORMANCE EVALUATION OF A SUSTAINABLE AND ENERGY EFFICIENT RE-ROOFING TECHNOLOGY USING FIELD-TEST DATA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Biswas, Kaushik; Miller, William A; Childs, Phillip W

    2011-01-01

    Three test attics were constructed to evaluate a new sustainable method of re-roofing utilizing photo-voltaic (PV) laminates, metal roofing panels, and PCM heat sink in the Envelope Systems Research Apparatus (ESRA) facility in the ORNL campus. Figure 1 is a picture of the three attic roofs located adjacent to each other. The leftmost roof is the conventional shingle roof, followed by the metal panel roof incorporating the cool-roof coating, and third from left is the roof with the PCM. On the PCM roof, the PV panels are seen as well; they're labelled from left-to-right as panels 5, 6 and 7.more » The metal panel roof consists of three metal panels with the cool-roof coating; in further discussion this is referred to as the infrared reflective (IRR) metal roof. The IRR metal panels reflect the incoming solar radiation and then quickly re-emit the remaining absorbed portion, thereby reducing the solar heat gain of the attic. Surface reflectance of the panels were measured using a Solar Spectrum Reflectometer. In the 0.35-2.0 {mu}m wavelength interval, which accounts for more than 94% of the solar energy, the IRR panels have an average reflectance of 0.303. In the infrared portion of the spectrum, the IRR panel reflectance is 0.633. The PCM roof consists of a layer of macro-encapsulated bio-based PCM at the bottom, followed by a 2-cm thick layer of dense fiberglass insulation with a reflective surface on top, and metal panels with pre-installed PV laminates on top. The PCM has a melting point of 29 C (84.2 F) and total enthalpy between 180 and 190 J/g. The PCM was macro-packaged in between two layers of heavy-duty plastic foil forming arrays of PCM cells. Two air cavities, between PCM cells and above the fiberglass insulation, helped the over-the-deck natural air ventilation. It is anticipated that during summer, this extra ventilation will help in reducing the attic-generated cooling loads. The extra ventilation, in conjunction with the PCM heat sink, are used to

  7. Structural Design and Monitoring Analysis of Foundation Pit Support in Yiwu Huishang Tiandi

    NASA Astrophysics Data System (ADS)

    Zhang, Chunsu

    2017-08-01

    Huishang Tiandi deep foundation pit in Yiwu is a two-story basement,which is located in the downtown area and adjacent to the city center main traffic trunk. The surrounding environment is too com-plex to slope. The excavation depth is large, the formation is weak and complex, and the groundwater level is high.In order to ensure the safety of the foundation wall and the surrounding environment, the deformation of the foundation pit support is strictly controlled, and the deformation and internal force of the foundation supporting structure and the surrounding building are monitored.The deformation law of the foundation pit is obtained through the analysis of the horizontal displacement, the deformation rate of the supporting struc-ture, the surrounding environment of the foundation pit and the internal force of the anchor cable. The relia-bility and rationality of the design of foundation pit support are verified. It is of reference value for the de-sign and construction of other deep foundation pit engineering in Yiwu area.

  8. [Analysis of the distribution of VOCs concentration field with oil static breathing loss in internal floating roof tank].

    PubMed

    Wu, Hong-Zhang; Huang, Wei-Qiu; Yang, Guang; Zhao, Chen-Lu; Wang, Ying-Xia; Cai, Dao-Fei

    2013-12-01

    Internal floating roof tank has the advantages of external floating roof tank and fixed roof tank and has its own evaporation loss properties. The influences of volatile organic compounds (VOCs) distribution gradient, molecular diffusion, thermal diffusion and forced convection on the evaporation loss of oil were studied in the space of the homemade platform of an internal floating roof tank. The results showed that thermal diffusion with temperature change was the main cause for the static loss in the internal floating roof tank. On this basis, there were some measures for reduction of the evaporation loss and formulas to calculate the evaporation loss of the internal floating roof tank in this research.

  9. How To Choose the Right Roofing System.

    ERIC Educational Resources Information Center

    Carl, David

    2001-01-01

    Lists the factors that must be considered when specifying a roof for an existing or new facility. Factors discussed include cost, longevity, value of operations, warranties, building structure and design, and old vs. new system compatibility. (GR)

  10. Investigation on the Influence of Abutment Pressure on the Stability of Rock Bolt Reinforced Roof Strata Through Physical and Numerical Modeling

    NASA Astrophysics Data System (ADS)

    Kang, Hongpu; Li, Jianzhong; Yang, Jinghe; Gao, Fuqiang

    2017-02-01

    In underground coal mining, high abutment loads caused by the extraction of coal can be a major contributor to many rock mechanic issues. In this paper, a large-scale physical modeling of a 2.6 × 2.0 × 1.0 m entry roof has been conducted to investigate the fundamentals of the fracture mechanics of entry roof strata subjected to high abutment loads. Two different types of roof, massive roof and laminated roof, are considered. Rock bolt system has been taken into consideration. A distinct element analyses based on the physical modeling conditions have been performed, and the results are compared with the physical results. The physical and numerical models suggest that under the condition of high abutment loads, the massive roof and the laminated roof fail in a similar pattern which is characterized as vertical tensile fracturing in the middle of the roof and inclined shear fracturing initiated at the roof and rib intersections and propagated deeper into the roof. Both the massive roof and the laminated roof collapse in a shear sliding mode shortly after shear fractures are observed from the roof surface. It is found that shear sliding is a combination of tensile cracking of intact rock and sliding on bedding planes and cross joints. Shear sliding occurs when the abutment load is much less than the compressive strength of roof.

  11. Green roof rainfall-runoff modelling: is the comparison between conceptual and physically based approaches relevant?

    NASA Astrophysics Data System (ADS)

    Versini, Pierre-Antoine; Tchiguirinskaia, Ioulia; Schertzer, Daniel

    2017-04-01

    Green roofs are commonly considered as efficient tools to mitigate urban runoff as they can store precipitation, and consequently provide retention and detention performances. Designed as a compromise between water holding capacity, weight and hydraulic conductivity, their substrate is usually an artificial media differentiating significantly from a traditional soil. In order to assess green roofs hydrological performances, many models have been developed. Classified into two categories (conceptual and physically based), they are usually applied to reproduce the discharge of a particular monitored green roof considered as homogeneous. Although the resulted simulations could be satisfactory, the question of robustness and consistency of the calibrated parameters is often not addressed. Here, a modeling framework has been developed to assess the efficiency and the robustness of both modelling approaches (conceptual and physically based) in reproducing green roof hydrological behaviour. SWMM and VS2DT models have been used for this purpose. This work also benefits from an experimental setup where several green roofs differentiated by their substrate thickness and vegetation cover are monitored. Based on the data collected for several rainfall events, it has been studied how the calibrated parameters are effectively linked to their physical properties and how they can vary from one green roof configuration to another. Although both models reproduce correctly the observed discharges in most of the cases, their calibrated parameters exhibit a high inconsistency. For a same green roof configuration, these parameters can vary significantly from one rainfall event to another, even if they are supposed to be linked to the green roof characteristics (roughness, residual moisture content for instance). They can also be different from one green roof configuration to another although the implemented substrate is the same. Finally, it appears very difficult to find any

  12. 75 FR 28316 - Notice of Buy America Waiver Request by Oregon Department of Transportation for Steel Roof Tiles...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-20

    ... by Oregon Department of Transportation for Steel Roof Tiles To Be Used in Union Station Roof... (``PRIIA'') (49 U.S.C. 24405(a)) for the purchase of metal roof tiles made of 40/45 KSI 2, 24 Gauge (0.0276... Register. This notice informs the public that ODOT has requested a Buy America waiver for the roofing tiles...

  13. An experimental investigation on the requirement of roof height and sill width for car ingress and egress.

    PubMed

    Causse, Julien; Wang, Xuguang; Denninger, Lisa

    2012-01-01

    This study aimed at experimentally investigating the influence of roof height and sill width on car ingress/egress movements. The first uncomfortable (Ht1) and the lowest acceptable (Ht2) roof heights were obtained from 26 participants of three different stature groups thanks to a multi-adjustable vehicle mock-up. Both Ht1 and Ht2 were affected neither by stature nor by vehicle type. Only a difference of 45 mm between Ht1 and Ht2 was observed. Tall volunteers more flexed the trunk and neck than short persons thanks to a larger space available around the seat when the head passing under the roof. The vehicle type had almost no effect on upper body posture. The roof height only affected neck flexion. The sill width mainly imposed a lateral translation. Results demonstrated that an appropriate roof height should be determined carefully. A small change of 45 mm in roof height may lead to an unacceptable situation. The present study experimentally investigated the effects of roof height and sill width on car ingress and egress movements. Short females required almost the same roof height as tall males due to smaller space around the seat. The results would help to optimise car dimensions for improving car accessibility.

  14. A common-sense approach to asbestos in roofing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Steinmetz, W.R. Jr.

    The word asbestos carries an ominous connotation to many plant engineers and building owners. Many are caught up in the hype surrounding asbestos abatement. Others are confused about how to face the questions surrounding this mysterious, dangerous, and often misunderstood substance. Asbestos issues cast a particularly perplexing spell over decisions about how to deal with the material in the removal of roofing systems. The product is an excellent roofing choice because it is fire-resistant, durable, and nonrotting. And most significantly on the other hand, asbestos causes three deadly diseases: lung cancer, asbestosis, and mesothelioma (cancer of the lung lining andmore » always fatal). This danger prompted enactment of the Asbestos Hazard Emergency Response Act (AHERA) in the early 1980s. The regulation required every K-12 school in the US to develop a management plant for dealing with asbestos. Since then, much has been done to raise awareness of the issues surrounding this material. The standard`s earliest form based removal requirements primarily on exposure levels. A 1994 revision, however, extended stringent removal requirements to all roof removal work involving asbestos, regardless of exposure level. This paper looks at the regulations, concerns, considerations, and procedures for dealing with the problem.« less

  15. Technology Solutions for New and Existing Homes Case Study: Optimized Slab-on-Grade Foundation Insulation Retrofits

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    T. Schirber; Goldberg, L.; Mosiman, G.

    A more accurate assessment of SOG foundation insulation energy savings than traditionally possible is now feasible. This has been enabled by advances in whole building energy simulation with 3-dimensional foundation modelling integration at each time step together with an experimental measurement of the site energy savings of SOG foundation insulation. Ten SOG insulation strategies were evaluated on a test building to identify an optimum retrofit insulation strategy in a zone 6 climate (Minneapolis, MN). The optimum insulation strategy in terms of energy savings and cost effectiveness consisted of two components: (a) R-20 XPS insulation above grade, and, (b) R-20 insulationmore » at grade (comprising an outer layer of R-10 insulation and an interior layer of R-12 poured polyurethane insulation) tapering to R-10 XPS insulation at half the below-grade wall height (the lower half of the stem wall was uninsulated).« less

  16. Characteristics of the Roof Behaviors and Mine Pressure Manifestations During the Mining of Steep Coal Seam

    NASA Astrophysics Data System (ADS)

    Hong-Sheng, Tu; Shi-Hao, Tu; Cun, Zhang; Lei, Zhang; Xiao-Gang, Zhang

    2017-12-01

    A steep seam similar simulation system was developed based on the geological conditions of a steep coal seam in the Xintie Coal Mine. Basing on similar simulation, together with theoretical analysis and field measurement, an in-depth study was conducted to characterize the fracture and stability of the roof of steep working face and calculate the width of the region backfilled with gangue in the goaf. The results showed that, as mining progressed, the immediate roof of the steep face fell upon the goaf and backfilled its lower part due to gravity. As a result, the roof in the lower part had higher stability than the roof in the upper part of the working face. The deformation and fracture of main roof mainly occurred in the upper part of the working face; the fractured main roof then formed a "voussoir beam" structure in the strata's dip direction, which was subjected to the slip- and deformation-induced instability. The stability analysis indicated that, when the dip angle increased, the rock masses had greater capacity to withstand slip-induced instability but smaller capacity to withstand deformation-induced instability. Finally, the field measurement of the forces exerted on the hydraulic supports proved the characteristics of the roof's behaviors during the mining of a steep seam.

  17. Improving the Method of Roof Fall Susceptibility Assessment based on Fuzzy Approach

    NASA Astrophysics Data System (ADS)

    Ghasemi, Ebrahim; Ataei, Mohammad; Shahriar, Kourosh

    2017-03-01

    Retreat mining is always accompanied by a great amount of accidents and most of them are due to roof fall. Therefore, development of methodologies to evaluate the roof fall susceptibility (RFS) seems essential. Ghasemi et al. (2012) proposed a systematic methodology to assess the roof fall risk during retreat mining based on risk assessment classic approach. The main defect of this method is ignorance of subjective uncertainties due to linguistic input value of some factors, low resolution, fixed weighting, sharp class boundaries, etc. To remove this defection and improve the mentioned method, in this paper, a novel methodology is presented to assess the RFS using fuzzy approach. The application of fuzzy approach provides an effective tool to handle the subjective uncertainties. Furthermore, fuzzy analytical hierarchy process (AHP) is used to structure and prioritize various risk factors and sub-factors during development of this method. This methodology is applied to identify the susceptibility of roof fall occurrence in main panel of Tabas Central Mine (TCM), Iran. The results indicate that this methodology is effective and efficient in assessing RFS.

  18. Near-wall modelling of compressible turbulent flows

    NASA Technical Reports Server (NTRS)

    So, Ronald M. C.

    1990-01-01

    Work was carried out to formulate near-wall models for the equations governing the transport of the temperature-variance and its dissipation rate. With these equations properly modeled, a foundation is laid for their extension together with the heat-flux equations to compressible flows. This extension is carried out in a manner similar to that used to extend the incompressible near-wall Reynolds-stress models to compressible flows. The methodology used to accomplish the extension of the near-wall Reynolds-stress models is examined and the actual extension of the models for the Reynolds-stress equations and the near-wall dissipation-rate equation to compressible flows is given. Then the formulation of the near-wall models for the equations governing the transport of the temperature variance and its dissipation rate is discussed. Finally, a sample calculation of a flat plate compressible turbulent boundary-layer flow with adiabatic wall boundary condition and a free-stream Mach number of 2.5 using a two-equation near-wall closure is presented. The results show that the near-wall two-equation closure formulated for compressible flows is quite valid and the calculated properties are in good agreement with measurements. Furthermore, the near-wall behavior of the turbulence statistics and structure parameters is consistent with that found in incompressible flows.

  19. The hydrological behaviour of extensive and intensive green roofs in a dry climate.

    PubMed

    Razzaghmanesh, M; Beecham, S

    2014-11-15

    This paper presents the results of a hydrological investigation of four medium scale green roofs that were set up at the University of South Australia. In this study, the potential of green roofs as a source control device was investigated over a 2 year period using four medium size green roof beds comprised of two growth media types and two media depths. During the term of this study, 226 rainfall events were recorded and these were representative of the Adelaide climate. In general, there were no statistically significant differences between the rainfall and runoff parameters for the intensive and extensive beds except for peak attenuation and peak runoff delay, for which higher values were recorded in the intensive beds. Longer dry periods generally resulted in higher retention coefficients and higher retention was also recorded in warmer seasons. The average retention coefficient for intensive systems (89%) was higher than for extensive systems (74%). It was shown that rainfall depth, intensity, duration and also average dry weather period between events can change the retention performance and runoff volume of the green roofs. Comparison of green and simulated conventional roofs indicated that the former were able to mitigate the peak of runoff and could delay the start of runoff. These characteristics are important for most source control measures. The recorded rainfall and runoff data displayed a non-linear relationship. Also, the results indicated that continuous time series modelling would be a more appropriate technique than using peak rainfall intensity methods for green roof design and simulation. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. 7. NHP, Water Turbine Section, north end of east wall ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. NHP, Water Turbine Section, north end of east wall of 1908-1909 vaulted concrete standpipe foundation. View is to the Northeast. - Nunn Hydroelectric Plant, On Madison River, Ennis, Madison County, MT

  1. Solar Air Heating Metal Roofing for Reroofing, New Construction, and Retrofit

    DTIC Science & Technology

    2013-05-20

    roof is installed starting the cycle over again. In contrast, metal roofing has a nominal service life of 40 years, can be recycled when removed and...energy, recycled content, innovation, air quality and other elements. American Solar intends to target trade publications, websites, and speaking...insulation with cloth jacket covered the bottom of the metal deck. The schematic Figure A-2, 3, shows the system as proposed at the

  2. Solar Air Heating Metal Roofing for Reroofing, New Construction, and Retrofit

    DTIC Science & Technology

    2013-06-01

    Fahrenheit ft2 square foot FY fiscal year GHG greenhouse gas HGL HydroGeoLogic, Inc. HVAC heating, ventilation and air-conditioning LPG Liquefied...the greenhouse gas emission reductions; and 6. Document the performance of the solar roof as it compares to a reflective “Cool Roof.” Among the...Orders, and Agency implementing directives and instructions require the reduction of energy use and greenhouse gas emissions, increased use of renewable

  3. Simulation tests to assess occupational exposure to airborne asbestos from artificially weathered asphalt-based roofing products.

    PubMed

    Sheehan, Patrick; Mowat, Fionna; Weidling, Ryan; Floyd, Mark

    2010-11-01

    Historically, asbestos-containing roof cements and coatings were widely used for patching and repairing leaks. Although fiber releases from these materials when newly applied have been studied, there are virtually no useful data on airborne asbestos fiber concentrations associated with the repair or removal of weathered roof coatings and cements, as most studies involve complete tear-out of old roofs, rather than only limited removal of the roof coating or cement during a repair job. This study was undertaken to estimate potential chrysotile asbestos fiber exposures specific to these types of roofing products following artificially enhanced weathering. Roof panels coated with plastic roof cement and fibered roof coating were subjected to intense solar radiation and daily simulated precipitation events for 1 year and then scraped to remove the weathered materials to assess chrysotile fiber release and potential worker exposures. Analysis of measured fiber concentrations for hand scraping of the weathered products showed 8-h time-weighted average concentrations that were well below the current Occupational Safety and Health Administration permissible exposure limit for asbestos. There was, however, visibly more dust and a few more fibers collected during the hand scraping of weathered products compared to the cured products previously tested. There was a notable difference between fibers released from weathered and cured roofing products. In weathered samples, a large fraction of chrysotile fibers contained low concentrations of or essentially no magnesium and did not meet the spectral, mineralogical, or morphological definitions of chrysotile asbestos. The extent of magnesium leaching from chrysotile fibers is of interest because several researchers have reported that magnesium-depleted chrysotile fibers are less toxic and produce fewer mesothelial tumors in animal studies than normal chrysotile fibers.

  4. Two-year Wisconsin thermal loads for roof assemblies and wood, wood–plastic composite, and fiberglass shingles

    Treesearch

    Jerrold E. Winandy; Michael Grambsch; Cherilyn Hatfield

    2005-01-01

    Temperature histories for various types of roof shingles, wood roof sheathing, roof rafters, and non-ventilated attics are being monitored in outdoor attic structures using simulated North American light-framed construction. This report presents 2-year data histories for annual thermal loads for western redcedar, wood–thermoplastic composite, and fiberglass shingles...

  5. Design and development of green roof substrate to improve runoff water quality: plant growth experiments and adsorption.

    PubMed

    Vijayaraghavan, K; Raja, Franklin D

    2014-10-15

    Many studies worldwide have investigated the potential benefits achievable by transforming brown roofs of buildings to green roofs. However, little literature examined the runoff quality/sorption ability of green roofs. As the green roof substrate is the main component to alter the quality of runoff, this investigation raises the possibility of using a mixture of low-cost inorganic materials to develop a green roof substrate. The tested materials include exfoliated vermiculite, expanded perlite, crushed brick and sand along with organic component (coco-peat). Detailed physical and chemical analyses revealed that each of these materials possesses different characteristics and hence a mix of these materials was desirable to develop an optimal green roof substrate. Using factorial design, 18 different substrate mixes were prepared and detailed examination indicated that mix-12 exhibited desirable characteristics of green roof substrate with low bulk density (431 kg/m(3)), high water holding capacity (39.4%), air filled porosity (19.5%), and hydraulic conductivity (4570 mm/h). The substrate mix also provided maximum support to Portulaca grandiflora (380% total biomass increment) over one month of growth. To explore the leaching characteristics and sorption capacity of developed green roof substrate, a down-flow packed column arrangement was employed. High conductivity and total dissolved solids along with light metal ions (Na, K, Ca and Mg) were observed in the leachates during initial stages of column operation; however the concentration of ions ceased during the final stages of operation (600 min). Experiments with metal-spiked deionized water revealed that green roof substrate possess high sorption capacity towards various heavy metal ions (Al, Fe, Cr, Cu, Ni, Pb, Zn and Cd). Thus the developed growth substrate possesses desirable characteristics for green roofs along with high sorption capacity. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Effect of substrate depth and rain-event history on the pollutant abatement of green roofs.

    PubMed

    Seidl, Martin; Gromaire, Marie-Christine; Saad, Mohamed; De Gouvello, Bernard

    2013-12-01

    This study compares the effectiveness of two different thickness of green roof substrate with respect to nutrient and heavy metal retention and release. To understand and evaluate the long term behaviour of green roofs, substrate columns with the same structure and composition as the green roofs, were exposed in laboratory to artificial rain. The roofs act as a sink for C, N, P, zinc and copper for small rain events if the previous period was principally dry. Otherwise the roofs may behave as a source of pollutants, principally for carbon and phosphorus. Both field and column studies showed an important retention for Zn and Cu. The column showed, however, lower SS, DOC and metal concentrations in the percolate than could be observed in the field even if corrected for run-off. This is most probably due to the difference in exposition history and weathering processes. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Evaluation on Thermal Behavior of a Green Roof Retrofit System Installed on Experimental Building in Composite Climate of Roorkee, India

    NASA Astrophysics Data System (ADS)

    Kumar, Ashok; Deoliya, Rajesh; Chani, P. S.

    2015-12-01

    Green roofs not only provide cooling by shading, but also by transpiration of water through the stomata. However, the evidence for green roofs providing significant air cooling remains limited. No literature investigates the thermal performance of prefab brick panel roofing technology with green roof. Hence, the aim of this research is to investigate the thermal behavior of an experimental room, built at CSIR-Central Building Research Institute (CBRI) campus, Roorkee, India using such roofing technology during May 2013. The study also explores the feasibility of green roof with grass carpets that require minimum irrigation, to assess the expected indoor thermal comfort improvements by doing real-time experimental studies. The results show that the proposed green roof system is suitable for reducing the energy demand for space cooling during hot summer, without worsening the winter energy performance. The cost of proposed retrofit system is about Rs. 1075 per m2. Therefore, green roofs can be used efficiently in retrofitting existing buildings in India to improve the micro-climate on building roofs and roof insulation, where the additional load carrying capacity of buildings is about 100-130 kg/m2.

  8. Plant establishment on unirrigated green roof modules in a subtropical climate

    PubMed Central

    Dvorak, Bruce D.; Volder, Astrid

    2012-01-01

    Background and aims The application of green roof technology has become more common in the central, northwestern and eastern USA, and is now being employed across the southern USA as well. However, there is little research in the literature that evaluated plant survival on unirrigated green roofs in subtropical climates that experience frequent drought and heat stress. Here, we summarize the results of a study of plant establishment on a modular green roof in south-central Texas. Methodology Fifteen plant species were field tested in 11.4-cm-deep green roof modules on a four-storey building in College Station, Texas, with irrigation limited to the first several weeks of establishment. Climate data, plant growth and species survival were measured over three growing seasons. Principal results Four species survived growing seasons without any losses: Graptopetalum paraguayense, Malephora lutea, Manfreda maculosa and Phemeranthus calycinus. Six species experienced varying levels of mortality: Bulbine frutescens, Delosperma cooperi, Lampranthus spectabilis, Sedum kamtschaticum, Sedum mexicanum and Nassella tenuissima. Five species had no survivors: Dichondra argentea, Stemodia lanata, Myoporum parvifolium, Sedum moranense and Sedum tetractinum. Conclusions The establishment and survival of several plant species without any mortality suggests that irrigation limited to the first few weeks after planting may be an effective approach on green roofs in spite of the more challenging climatic conditions in the southern USA. Since the climate in south-central Texas had been consistently drier and warmer than normal during the study period, longer-term research on these species is recommended to expand knowledge of establishment requirements for these species under a wider range of conditions, including wetter than normal years.

  9. A Web-Based Simulation Tool on The Performance of Different Roofing Systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Huang, Joe; New, Joshua Ryan; Miller, William A

    The Roof Savings Calculator (www.roofcalc.com) provides the general public with a web-based program for calculating the energy savings of different roofing and attic systems on four different building types (residential, office, retail, and warehouse) in 239 US TMY2 locations. The core simulation engine of the RSC is doe2attic, which couples the AtticSim program developed by Oak Ridge National Laboratory with the DOE-2.1E program originally developed by Lawrence Berkeley National Laboratory a widely used whole-building simulation program since the 1980 s. Although simulating heat flows through the roof may seem to be an easy task, simulating the net effect of roofingmore » strategies on building heating and cooling energy use can be quite challenging. Few simulation programs can reliably capture dynamics including an attic or plenum with large day-night temperature swings, high ventilation rates, significant radiant exchange between the roof and the attic floor and thermal interactions when there are ducts in the attic, as is typical in North American buildings. The doe2attic program has been tested against detailed measurements gathered in two residential buildings in Fresno, California from cooling energy use to air and surface temperatures, and heat fluxes of the roof and attic floor. The focus of this paper is on the doe2attic simulation tool, but the user interface of the RSC will also be briefly described.« less

  10. Flexible roof drill for low coal. Volume 2. Phase III and Phase IV

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shoup, N.H.

    1977-09-01

    Design specifications were developed for a flexible drilling and bolting system. The system configuration is based on the use of the Galis dual-boom roof drill as a vehicle for the drilling/bolting system. The WSU Flex-drill drivehead is mounted on the Galis drill boom and the Galis parts are modified to accommodate the revised system. The flexible drillhead supports a bolt bender/inserter designed by Bendix Corporation and is integrated into the system operation. A supplemental bolt thruster was designed to complete insertion of the roof bolt following operation and removal of the Bendix bender from the bolt shank. The complete cyclemore » of drilling a 1-3/8-in. diameter bolt hole, bending a roof bolt into the hole, thrusting the bolt head and washer to the roof surface, and final torquing of the bolt is manually controlled by the operator located in the new position behind the bolting line. The new operating position is beneath newly bolted roof in a safer location in back of the stab jack ad roof jacks positioning the drill boom and drivehead. The Flex-drill/bolting system prototype was constructed from both purchased components and parts specially fabricated in the shops for this design. This unit was assembled and test-operated with appropriate support equipment in a laboratory test stand. Numerous test holes were drilled in blocks of concrete at feed rates of 5 ft/min with drill rotation speeds of 360 rpm. The drill feeds uniformly and cuts smoothly with no difficulty in collection of dust or clogging of the drill bit. The holes drilled were straight, as evidence by passage of a 1-1/4-in. diameter bar full depth into the hole with no binding or evidence of curvature. The flexible drill is capable of drilling 8-ft-deep roof bolt holes in low coal 36 in. in height.« less

  11. 30 CFR 75.204 - Roof bolting.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) Bearing plates used directly against the mine roof shall be at least 6 inches square or the equivalent... or the equivalent may be used. (3) Bearing plates used with wood or metal materials shall be at least 4 inches square or the equivalent. (4) Wooden materials that are used between a bearing plate and...

  12. 30 CFR 75.204 - Roof bolting.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) Bearing plates used directly against the mine roof shall be at least 6 inches square or the equivalent... or the equivalent may be used. (3) Bearing plates used with wood or metal materials shall be at least 4 inches square or the equivalent. (4) Wooden materials that are used between a bearing plate and...

  13. 30 CFR 75.204 - Roof bolting.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) Bearing plates used directly against the mine roof shall be at least 6 inches square or the equivalent... or the equivalent may be used. (3) Bearing plates used with wood or metal materials shall be at least 4 inches square or the equivalent. (4) Wooden materials that are used between a bearing plate and...

  14. 30 CFR 75.204 - Roof bolting.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) Bearing plates used directly against the mine roof shall be at least 6 inches square or the equivalent... or the equivalent may be used. (3) Bearing plates used with wood or metal materials shall be at least 4 inches square or the equivalent. (4) Wooden materials that are used between a bearing plate and...

  15. Effects of Building‒roof Cooling on Flow and Distribution of Reactive Pollutants in street canyons

    NASA Astrophysics Data System (ADS)

    Park, S. J.; Choi, W.; Kim, J.; Jeong, J. H.

    2016-12-01

    The effects of building‒roof cooling on flow and dispersion of reactive pollutants were investigated in the framework of flow dynamics and chemistry using a coupled CFD‒chemistry model. For this, flow characteristics were analyzed first in street canyons in the presence of building‒roof cooling. A portal vortex was generated in street canyon, producing dominant reverse and outward flows near the ground in all the cases. The building‒roof cooling increased horizontal wind speeds at the building roof and strengthened the downward motion near the downwind building in the street canyon, resultantly intensifying street canyon vortex strength. The flow affected the distribution of primary and secondary pollutants. Concentrations of primary pollutants such as NOx, VOC and CO was high near the upwind building because the reverse flows were dominant at street level, making this area the downwind region of emission sources. Concentration of secondary pollutant such as O3 was lower than the background near the ground, where NOX concentrations were high. Building‒roof cooling decreased the concentration of primary pollutants in contrasted to those under non‒cooling conditions. In contrast, building‒roof cooling increased O3 by reducing NO concentrations in urban street canyon compared to concentrations under non‒cooling conditions.

  16. Extensive green roof CO2 exchange and its seasonal variation quantified by eddy covariance measurements.

    PubMed

    Heusinger, Jannik; Weber, Stephan

    2017-12-31

    The CO 2 surface-atmosphere exchange of an unirrigated, extensive green roof in Berlin, Germany was measured by means of the eddy covariance method over a full annual cycle. The present analysis focusses on the cumulative green roof net ecosystem exchange of CO 2 (NEE), on its seasonal variation and on green roof physiological characteristics by applying a canopy (A-g s ) model. The green roof was a carbon sink with an annual cumulative NEE of -313gCO 2 m -2 year - 1 , equivalent to -85gCm -2 year - 1 . Three established CO 2 flux gap-filling methods were applied to estimate NEE and to study the performance during different meteorological situations. A best estimate NEE time series was established, which chooses the gap filling method with the highest performance. During dry periods daytime carbon uptake was shown to decline linearly with substrate moisture below a threshold of 0.05m 3 m -3 , whereas night-time respiration was unaffected by substrate moisture variation. The roof turned into a temporary C source during dry conditions in summer 2015. We conclude that the carbon uptake of the present green roof can be optimized when substrate moisture is kept above 0.05m 3 m -3 . Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Effectiveness of foam-based and traditional green roofs in reducing nitrogen, phosphorus, organic carbon and suspended solids in urban installations

    NASA Astrophysics Data System (ADS)

    MacAvoy, S. E.; Mucha, S.; Williamson, G.

    2017-12-01

    While green roofs have well understood benefits for retaining runoff, there is less of a consensus regarding the potential for retaining and absorbing nutrients or suspended solids from roof runoff that would otherwise travel to waterways. Additionally, there are numerous designs, materials and maintenance plans associated with "green" roofs/surfaces that may greatly impact not only their hydrological benefit but also their pollution mitigation potential. Here we examine the NO3, NH4, total organic carbon (TOC), total phosphorus (TP) and total suspended solids (TSS) retention potential from planted and unplanted foam roofs and traditional soil roofs. Direct precipitation, untreated runoff and throughflow from the different roof types were collected for 3 to 11 rain events over a year (depending on roof). Unplanted and traditional roofs reduced TSS by 80% or better relative to runoff. Traditional roofs showed 50% lower TP than runoff or other roof types. TOC was higher than direct precipitation for all treatments, although there were no differences among the treatments themselves. Taken as averages over the 11 events, NO3 and NH4 concentrations were highly variable for runoff and treatments and significant differences were not detected. Preliminary analysis suggests there were no differences between performance of traditional versus foam-based roofs, although a greater sample size is required to be definitive.

  18. Nitrogen and phosphorus associating with different size suspended solids in roof and road runoff in Beijing, China.

    PubMed

    Wu, Junliang; Ren, Yufen; Wang, Xuemei; Wang, Xiaoke; Chen, Liding; Liu, Gangcai

    2015-10-01

    Roofs and roads, accounting for a large portion of the urban impervious land surface, have contributed significantly to urban nonpoint pollution. In this study, in Beijing, China, roof and road runoff are sampled to measure the suspended solids (SS), nitrogen (N), and phosphorus (P) contained in particles with different sizes. The SS content in the road runoff (151.59 mg/L) was sevenfold that in the roof runoff (21.13 mg/L, p < 0.05). The SS contained more coarse particulates in the roof runoff than in road runoff. The small particulates in the range of 0.45-50 μm consisted of 59 % SS in the roof runoff and 94 % SS in the road runoff. P was mainly attached to particle sizes of 10-50 μm in the roof (73 %) and road (48 %) runoffs, while N was mainly in a dissolved phase state in both runoffs. So, the different associations of N and P raise a challenge in preventing stormwater pollution in urban environments.

  19. Report on the Failure of Roof Beams at Sir John Cass's Foundation and Red Coat Church of England Secondary School, Stepney. Building Research Establishment Current Paper 58/74.

    ERIC Educational Resources Information Center

    Bate, S. C. C.

    Two beams forming part of the roof over the swimming pool at the school collapsed. The investigation showed that the cause of the failure was loss of strength due to conversion of high alumina cement concrete followed by sulphate attack leading to disruption of the concrete. The degree of conversion and loss of strength was greater than expected…

  20. External Insulation of Masonry Walls and Wood Framed Walls

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Baker, P.

    2013-01-01

    The use of exterior insulation on a building is an accepted and effective means to increase the overall thermal resistance of the assembly that also has other advantages of improved water management and often increased air tightness of building assemblies. For thin layers of insulation (1" to 1 1/2"), the cladding can typically be attached directly through the insulation back to the structure. For thicker insulation layers, furring strips have been added as a cladding attachment location. This approach has been used in the past on numerous Building America test homes and communities (both new and retrofit applications), and hasmore » been proven to be an effective and durable means to provide cladding attachment. However, the lack of engineering data has been a problem for many designers, contractors, and code officials. This research project developed baseline engineering analysis to support the installation of thick layers of exterior insulation on existing masonry and frame walls. Furthermore, water management details necessary to integrate windows, doors, decks, balconies and roofs were created to provide guidance on the integration of exterior insulation strategies with other enclosure elements.« less

  1. External Insulation of Masonry Walls and Wood Framed Walls

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Baker, P.

    2013-01-01

    The use of exterior insulation on a building is an accepted and effective means to increase the overall thermal resistance of the assembly that also has other advantages of improved water management and often increased air tightness of building assemblies. For thin layers of insulation (1” to 1 ½”), the cladding can typically be attached directly through the insulation back to the structure. For thicker insulation layers, furring strips have been added as a cladding attachment location. This approach has been used in the past on numerous Building America test homes and communities (both new and retrofit applications), and hasmore » been proven to be an effective and durable means to provide cladding attachment. However, the lack of engineering data has been a problem for many designers, contractors, and code officials. This research project developed baseline engineering analysis to support the installation of thick layers of exterior insulation on existing masonry and frame walls. Furthermore, water management details necessary to integrate windows, doors, decks, balconies and roofs were created to provide guidance on the integration of exterior insulation strategies with other enclosure elements.« less

  2. ADVANCED HEAT TRANSFER TEST FACILITY, TRA666A. ELEVATIONS. ROOF FRAMING PLAN. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    ADVANCED HEAT TRANSFER TEST FACILITY, TRA-666A. ELEVATIONS. ROOF FRAMING PLAN. CONCRETE BLOCK SIDING. SLOPED ROOF. ROLL-UP DOOR. AIR INTAKE ENCLOSURE ON NORTH SIDE. F.C. TORKELSON 842-MTR-666-A5, 8/1966. INL INDEX NO. 531-0666-00-851-152258, REV. 2. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  3. Influence of plant composition and water use strategies on green roof stormwater retention.

    PubMed

    Zhang, Zheng; Szota, Christopher; Fletcher, Tim D; Williams, Nicholas S G; Werdin, Joerg; Farrell, Claire

    2018-06-01

    Green roofs are increasingly being considered a promising engineered ecosystem for reducing stormwater runoff. Plants are a critical component of green roofs and it has been suggested that plants with high water use after rainfall, but which are also drought tolerant, can improve rainfall retention on green roofs. However, there is little evidence to show how plants with different water use strategies will affect green roof retention performance, either in monocultures or in mixed plantings. This study tested how monocultures and a mixture of herbaceous species (Dianella admixta, Lomandra longifolia and Stypandra glauca) affected rainfall retention on green roofs. These species were chosen based on their water use strategies and compared with a commonly used succulent species (Sedum pachyphyllum) with conservative water use. We measured retention performance for 67 rainfall events, quantifying all components of the water balance. We also compared growth for species in monocultures and mixtures. We found that monocultures of L. longifolia had the greatest stormwater retention and ET. Although S. glauca has a similar water use strategy to D. admixta, it had the lowest stormwater retention and ET. In both the mixture and as a monoculture, S. glauca created preferential flow pathways, resulting in lower substrate water contents which reduced ET and therefore rainfall retention. This species also dominated performance of the mixture, such that the mixture had lower ET and retention than all monocultures (except S. glauca). We suggest that root traits and their interaction with substrates should be considered alongside water use strategies for rainfall retention on green roofs. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Housing conditions and Plasmodium falciparum infection: protective effect of iron-sheet roofed houses.

    PubMed

    Yé, Yazoumé; Hoshen, Moshe; Louis, Valérie; Séraphin, Simboro; Traoré, Issouf; Sauerborn, Rainer

    2006-02-01

    Identification and better understanding of potential risk factors for malaria are important for targeted and cost-effective health interventions. Housing conditions have been suggested as one of the potential risk factors. This study aims to further investigate this risk factor, and is focused on the effect of the type of roof on Plasmodium falciparum infection among children below five years in the North West of Burkina Faso. In a cross-sectional study design, 661 children aged six to 60 months were randomly selected from three rural and one semi-urban site at the end of the rainy season (November 2003). The children were screened for fever and tested for Plasmodium falciparum infection. In addition, data on bed net use and house characteristics was collected from the household were each child lived. Using adjusted odds ratios, children living in house roofed with iron-sheet were compared with those in house with mud or grass roof. Overall P. falciparum infection prevalence was 22.8 % with a significant variation between (Chi-square, p < 0.0001). The prevalence in Cissé (33.3 %) and Goni (30.6 %) were twice times more than in Nouna (15.2 %) and Kodougou (13.2 %). After adjusting for age, sex, use of bed net and housing conditions, children living in houses with mud roofs had significantly higher risk of getting P. falciparum infection compared to those living in iron-sheet roofed houses (Odds Ratio 2.6; 95% Confidence Interval, 1.4-4.7). These results suggest that house characteristics should be taken into consideration when designing health intervention against P. falciparum infection and particular attention should be paid to children living in houses with mud roofs.

  5. Building America Case Study: Optimized Slab-on-Grade Foundation Insulation Retrofits, Madison, Wisconsin

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    A more accurate assessment of SOG foundation insulation energy savings than traditionally possible is now feasible. This has been enabled by advances in whole building energy simulation with 3-dimensional foundation modelling integration at each time step together with an experimental measurement of the site energy savings of SOG foundation insulation. Ten SOG insulation strategies were evaluated on a test building to identify an optimum retrofit insulation strategy in a zone 6 climate (Minneapolis, MN). The optimum insulation strategy in terms of energy savings and cost effectiveness consisted of two components: (a) R-20 XPS insulation above grade, and, (b) R-20 insulationmore » at grade (comprising an outer layer of R-10 insulation and an interior layer of R-12 poured polyurethane insulation) tapering to R-10 XPS insulation at half the below-grade wall height (the lower half of the stem wall was uninsulated). The optimum insulation strategy was applied to single and multi-family residential buildings in climate zone 4 - 7. The highest site energy savings of 5% was realized for a single family home in Duluth, MN, and the lowest savings of 1.4 percent for a 4-unit townhouse in Richmond, VA. SOG foundation insulation retrofit simple paybacks ranged from 18 to 47 years. There are other benefits of SOG foundation insulation resulting from the increase in the slab surface temperatures. These include increased occupant thermal comfort, and a decrease in slab surface condensation particularly around the slab perimeter.« less

  6. Section NN, showing steel roof trusses, mezzanine iron railing, first ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Section NN, showing steel roof trusses, mezzanine iron railing, first floor doors, etc. San Bernardino Valley Union Junior College, Library Building. Also includes steel truss roof plan and a small stress diagram of the truss. Howard E. Jones, Architect, San Bernardino, California. Sheet 8, job no. 315. Scales 1/2 inch to the foot (section), and 1/8 and 1/16 inch to the foot. No date given on sheet (probably March or April, 1927). - San Bernardino Valley College, Library, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

  7. D0 Silicon Upgrade: Lower Cleanroom Roof Quick Load Analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rucinski, Russ; /Fermilab

    1995-11-17

    This engineering note documents calculations done to determine the margin of safety for the lower clean room roof. The analysis was done to give me a feeling of what the loads, stresses and capacity of the roof is prior to installation and installation work to be done for the helium refrigerator upgrade. The result of this quick look showed that the calculated loads produce stress values and loads at about half the allowables. Based on this result, I do not think that special precautions above personal judgement are required for the installation work.

  8. SECOND FLOOR AND ROOF PLANS. United Engineering Company Ltd., Alameda ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    SECOND FLOOR AND ROOF PLANS. United Engineering Company Ltd., Alameda Shipyard, Ship Repair Facilities, Office Building. Second floor plan, and roof plan. John Hudspeth, Architect, at foot of Main Street, Alameda, Calif. Sheet no. A2 of 8 sheets, Plan no. 10,007. Scale 1/8 inch to the foot. March 18, 1942, last revised 9/22/43. U.S. Navy, Bureau of Yards & Docks, Contract no. bs 76. Approved for construction October 9, 1943. blueprint - United Engineering Company Shipyard, Office Building No. 137, 2900 Main Street, Alameda, Alameda County, CA

  9. Designing Roads and Retaining Structures for Nangarhar Province, Afghanistan

    DTIC Science & Technology

    2011-01-01

    exist, typically using burnt brick masonry, with or without a frame, and with a reinforced concrete foundation, columns, stairs, and roofs. These...is 20 ×10 ×5 or 6 cm. The bricks are held in place with a mud mortar. Burnt bricks are placed at the top of two layers of a wall to protect against...conglomerate rocks appeared to be fragmental, such that the pieces are similar to broken concrete . The sandstone is characterized by a gritty sandpaper feel

  10. How EPA's Asbestos Regulations Apply to Roofing Materials

    EPA Pesticide Factsheets

    Guidance Manual and letters that clarify the applicability of the asbestos National Emissions Standard for Hazardous Air Pollutants (NESHAP) to the removal of asbestos-containing roofing material including tiles, and piping during demolition

  11. Performance Evaluation of Advanced Retrofit Roof Technologies Using Field-Test Data Phase Three Final Report, Volume 2

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Biswas, Kaushik; Childs, Phillip W.; Atchley, Jerald Allen

    2015-01-01

    This article presents some miscellaneous data from two low-slope and two steep-slope experimental roofs. The low-slope roofs were designed to compare the performance of various roof coatings exposed to natural weatherization. The steep-slope roofs contained different combinations of phase change material, rigid insulation, low emittance surface and above-sheathing ventilation, with standing-seam metal panels on top. The steep-slope roofs were constructed on a series of adjacent attics separated at the gables using thick foam insulation. This article describes phase three (3) of a study that began in 2009 to evaluate the energy benefits of a sustainable re-roofing technology utilizing standing-seam metalmore » roofing panels combined with energy efficient features like above-sheathing-ventilation (ASV), phase change material (PCM) and rigid insulation board. The data from phases 1 and 2 have been previously published and reported [Kosny et al., 2011; Biswas et al., 2011; Biswas and Childs, 2012; Kosny et al., 2012]. Based on previous data analyses and discussions within the research group, additional test roofs were installed in May 2012, to test new configurations and further investigate different components of the dynamic insulation systems. Some experimental data from phase 3 testing from May 2012 to December 2013 and some EnergyPlus modeling results have been reported in volumes 1 and 3, respectively, of the final report [Biswas et al., 2014; Biswas and Bhandari, 2014].« less

  12. Benzalkonium runoff from roofs treated with biocide products - In situ pilot-scale study.

    PubMed

    Gromaire, M C; Van de Voorde, A; Lorgeoux, C; Chebbo, G

    2015-09-15

    Roof maintenance practices often involve the application of biocide products to fight against moss, lichens and algae. The main component of these products is benzalkonium chloride, a mixture of alkyl benzyl dimethyl ammonium chlorides with mainly C12 and C14 alkyl chain lengths, which is toxic for the aquatic environment. This paper describes, on the basis of an in-situ pilot scale study, the evolution of roof runoff contamination over a one year period following the biocide treatment of roof frames. Results show a major contamination of roof runoff immediately after treatment (from 5 to 30 mg/L), followed by an exponential decrease. 175-375 mm of cumulated rainfall is needed before the runoff concentrations become less than EC50 values for fish (280 μg/l). The residual concentration in the runoff water remains above 4 μg/L even after 640 mm of rainfall. The level of benzalkonium ions leaching depends on the roofing material, with lower concentrations and total mass leached from ceramic tiles than from concrete tiles, and on the state of the tile (new or worn out). Mass balance calculations indicate that a large part of the mass of benzalkonium compounds applied to the tiles is lost, probably due to biodegradation processes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Influence of the Roof Movement Control Method on the Stability of Remnant

    NASA Astrophysics Data System (ADS)

    Adach-Pawelus, Karolina

    2017-12-01

    In the underground mines, there are geological and mining situations that necessitate leaving behind remnants in the mining field. Remnants, in the form of small, irregular parcels, are usually separated in the case of: significant problems with maintaining roof stability, high rockburst hazard, the occurrence of complex geological conditions and for random reasons (ore remnants), as well as for economic reasons (undisturbed rock remnants). Remnants left in the mining field become sites of high stress values concentration and may affect the rock in their vicinity. The values of stress inside the remnant and its vicinity, as well as the stability of the remnant, largely depend on the roof movement control method used in the mining field. The article presents the results of the numerical analysis of the influence of roof movement control method on remnant stability and the geomechanical situation in the mining field. The numerical analysis was conducted for the geological and mining conditions characteristic of Polish underground copper mines owned by KGHM Polska Miedz S.A. Numerical simulations were performed in a plane strain state by means of Phase 2 v. 8.0 software, based on the finite element method. The behaviour of remnant and rock mass in its vicinity was simulated in the subsequent steps of the room and pillar mining system for three types of roof movement control method: roof deflection, dry backfill and hydraulic backfill. The parameters of the rock mass accepted for numerical modelling were calculated by means of RocLab software on the basis of the Hoek-Brown classification. The Mohr-Coulomb strength criterion was applied.

  14. Water quantity and quality response of a green roof to storm events: Experimental and monitoring observations.

    PubMed

    Carpenter, Corey M G; Todorov, Dimitar; Driscoll, Charles T; Montesdeoca, Mario

    2016-11-01

    Syracuse, New York is working under a court-ordered agreement to limit combined sewer overflows (CSO) to local surface waters. Green infrastructure technologies, including green roofs, are being implemented as part of a CSO abatement strategy and to develop co-benefits of diminished stormwater runoff, including decreased loading of contaminants to the wastewater system and surface waters. The objective of this study was to examine the quantity and quality of discharge associated with precipitation events over an annual cycle from a green roof in Syracuse, NY and to compare measurements from this monitoring program with results from a roof irrigation experiment. Wet deposition, roof drainage, and water quality were measured for 87 storm events during an approximately 12 month period over 2011-2012. Water and nutrient (total phosphorus, total nitrogen, and dissolved organic carbon) mass balances were conducted on an event basis to evaluate retention annually and during the growing and non-growing seasons. These results are compared with a hydrological manipulation experiment, which comprised of artificially watering of the roof. Loadings of nutrients were calculated for experimental and actual storms using the concentration of nutrients and the flow data of water discharging the roof. The green roof was effective in retaining precipitation quantity from storm events (mean percent retention 96.8%, SD = 2.7%, n = 87), although the relative fraction of water retained decreased with increases in the size of the event. There was no difference in water retention of the green roof for the growing and non-growing seasons. Drainage waters exhibited high concentration of nutrients during the warm temperature growing season, particularly total nitrogen and dissolved organic carbon. Overall, nutrient losses were low because of the strong retention of water. However, there was marked variation in the retention of nutrients by season due to variations in concentrations in roof

  15. A generic hydrological model for a green roof drainage layer.

    PubMed

    Vesuviano, Gianni; Stovin, Virginia

    2013-01-01

    A rainfall simulator of length 5 m and width 1 m was used to supply constant intensity and largely spatially uniform water inflow events to 100 different configurations of commercially available green roof drainage layer and protection mat. The runoff from each inflow event was collected and sampled at one-second intervals. Time-series runoff responses were subsequently produced for each of the tested configurations, using the average response of three repeat tests. Runoff models, based on storage routing (dS/dt = I-Q) and a power-law relationship between storage and runoff (Q = kS(n)), and incorporating a delay parameter, were created. The parameters k, n and delay were optimized to best fit each of the runoff responses individually. The range and pattern of optimized parameter values was analysed with respect to roof and event configuration. An analysis was performed to determine the sensitivity of the shape of the runoff profile to changes in parameter values. There appears to be potential to consolidate values of n by roof slope and drainage component material.

  16. Using soil microbial inoculations to enhance substrate performance on extensive green roofs.

    PubMed

    Molineux, Chloe J; Gange, Alan C; Newport, Darryl J

    2017-02-15

    Green roofs are increasing in popularity in the urban environment for their contribution to green infrastructure; but their role for biodiversity is not often a design priority. Maximising biodiversity will impact positively on ecosystem services and is therefore fundamental for achieving the greatest benefits from green roofs. Extensive green roofs are lightweight systems generally constructed with a specialised growing medium that tends to be biologically limited and as such can be a harsh habitat for plants to thrive in. Thus, this investigation aimed to enhance the soil functioning with inoculations of soil microbes to increase plant diversity, improve vegetation health/performance and maximise access to soil nutrients. Manipulations included the addition of mycorrhizal fungi and a microbial mixture ('compost tea') to green roof rootzones, composed mainly of crushed brick or crushed concrete. The study revealed that growing media type and depth play a vital role in the microbial ecology of green roofs, with complex relationships between depth and type of substrate and the type of microbial inoculant applied, with no clear pattern being observed. For bait plant measurements (heights, leaf numbers, root/shoot biomass, leaf nutrients), a compost tea may have positive effects on plant performance when grown in substrates of shallower depths (5.5cm), even one year after inoculums are applied. Results from the species richness surveys show that diversity was significantly increased with the application of an AM fungal treatment and that overall, results suggest that brick-based substrate blends are most effective for vegetation performance as are deeper depths (although this varied with time). Microbial inoculations of green roof habitats appeared to be sustainable; they need only be done once for benefits to still been seen in subsequent years where treatments are added independently (not in combination). They seem to be a novel and viable method of enhancing

  17. Volcanic ashfall accumulation and loading on gutters and pitched roofs from laboratory empirical experiments: Implications for risk assessment

    NASA Astrophysics Data System (ADS)

    Hampton, S. J.; Cole, J. W.; Wilson, G.; Wilson, T. M.; Broom, S.

    2015-10-01

    Volcanic ash load is dependent on the migration and accumulation of ash on roofing surfaces and guttering, of which limited research has been conducted. This study investigates this knowledge gap through the empirical experimental testing of volcanic ash on variably pitched metal sheet roofs with modern PVC gutter systems, highlighting the relative importance of accumulation, migration, remobilization, saturation, and subsequent load. A testing rig delivered ash onto variably pitched roofs (pitches 15°, 25°, 30°, 35°, and 45°) with two 45° tests involving a wet surface with subsequent ashfall, and the second of ashfall with periods of wetting, followed by wetting until failure. In testing, dry ash on a dry roof accumulates at pitches up to 35°, above this pitch the percentage of ash accumulating reduces with greater percentages infilling guttering and or lost to the ground. With the introduction of a wet roof surface at 45° pitch, adherence of dry ash greatly increases, increasing accumulated ash thickness as compared to dry tests from 8% to 38%. For testing involving periods of wetting at 45° roof pitch, accumulation percentages further increased to 50%. Ash migrating from the roof surface filled guttering more rapidly at greater pitches, which once full resulted in further migrating ash to spill over the front or back gutter lips. Collapse of guttering did not occur during testing, but deformation and bracket detachment did occur at loads > 1 kPa. This study provides data on load calculations on roofing and PVC guttering through the quantification and utilization of relationships between ash fate, pitch, and the influence of water, in the development of two scenarios for both roof and gutter. These two scenarios then enable the estimation of ash accumulation and thus the load and collapse thresholds for roof and gutter at different roof pitch, which could be adopted for volcanic risk modeling or risk management.

  18. Heat transfer capability of solar radiation in colored roof and influence on room thermal comfort

    NASA Astrophysics Data System (ADS)

    Syuhada, Ahmad; Maulana, Muhammad Ilham

    2018-02-01

    Colored zinc is the most widely used by people in Indonesia as the roof of the building. Each color has different heat absorption capability, the higher the absorption capacity of a roof will cause high room temperature. A high temperature in the room will cause the room is not thermally comfortable for activity. Lack of public knowledge about the ability of each color to absorb heat can cause errors in choosing the color of the roof of the building so that it becomes uncomfortable regarding thermal comfort. This study examined how big the ability of each color in influencing the heat absorption on the roof of the zinc. The purpose of this study is to examine which colors are the lowest to absorb radiation heat. This research used theexperimental method. Data collected by measuring the temperature of the environment above and below the colored tin roof, starting at 11:00 am until 15:00 pm. The zinc roofs tested in this study are zinc black, red zinc, green zinc, blue zinc, brown zinc, maroon zinc, orange zinc, zinc gray, zinc color chrome and zinc white color. The study results show that black and blackish colors will absorb more heat than other colors. While the color white or close to whitish color will absorb a slight heat.

  19. 30 CFR 75.211 - Roof testing and scaling.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... examination does not disclose a hazardous condition, sound and vibration roof tests, or other equivalent tests, shall be made where supports are to be installed. When sound and vibration tests are made, they shall be...

  20. 30 CFR 75.211 - Roof testing and scaling.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... examination does not disclose a hazardous condition, sound and vibration roof tests, or other equivalent tests, shall be made where supports are to be installed. When sound and vibration tests are made, they shall be...

Some links on this page may take you to non-federal websites. Their policies may differ from this site.