Hail Resistance of Roofing ProductsBuilding Research Division, U.S. Institute for Applied Technology, 1969 - 9 pages A test was developed for evaluating the hail resistance of roofings, in which synthetic hailstones (ice spheres) of various sizes were shot at roof assemblies at their free-fall terminal v * elocities.Indentations, granule loss and roofing fracture were observed.The principal conclusion is that:All roofing materials have some resistance to hail damage, but as the size of the hail increases, a level of impact energy is reached at which damage occurs.This level lies in the range of 1 1/2 to 2 inch (3.8-5.1 cm) hailstones for most prepared roofings.(Author). |
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... Specimen construction 3. Procedures 3.1 . Shooting hailstones at roofing 3.2 . Evaluating failure 4. Results 4.1 . Asphalt shingles 4.2 . Built - up roofs 4.3 . Nonbituminous roofing 5. Conclusions 6. References 9 9 66 Hail Resistance ...
... Specimen construction 3. Procedures 3.1 . Shooting hailstones at roofing 3.2 . Evaluating failure 4. Results 4.1 . Asphalt shingles 4.2 . Built - up roofs 4.3 . Nonbituminous roofing 5. Conclusions 6. References 9 9 66 Hail Resistance ...
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... specimen to be tested . The physical layout of the apparatus is shown in figure 2 . The apparatus consisted of a specimen ( tar- get ) area ( 1 ) , timing range ( 2 ) , gas gun ( 3 ) , gas cylinder ( 4 ) , timer ( 5 ) , hailstone ...
... specimen to be tested . The physical layout of the apparatus is shown in figure 2 . The apparatus consisted of a specimen ( tar- get ) area ( 1 ) , timing range ( 2 ) , gas gun ( 3 ) , gas cylinder ( 4 ) , timer ( 5 ) , hailstone ...
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... specimen . 2. Timing section . 3. Compressed gas gun . 4. Gas cylinder . 5. Timer . 6. Hailstone carriers - one in ... Specimen Construction The shingle specimens were applied with four staples ( per strip ) to 1 ft 6 in x 3 ft 0 in ( 46 ...
... specimen . 2. Timing section . 3. Compressed gas gun . 4. Gas cylinder . 5. Timer . 6. Hailstone carriers - one in ... Specimen Construction The shingle specimens were applied with four staples ( per strip ) to 1 ft 6 in x 3 ft 0 in ( 46 ...
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... specimen . The indentation on the specimen was meas- ured and the condition of the specimen noted after each firing . A minimum of two hits in each area of vulnerability was observed and average values of damage used . Granule losses ...
... specimen . The indentation on the specimen was meas- ured and the condition of the specimen noted after each firing . A minimum of two hits in each area of vulnerability was observed and average values of damage used . Granule losses ...
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... specimens were also exposed to 11 / 4 - in dentations were made in the shingles by the ( 3.2 cm ) hailstones . Only small , superficial in- 114 - in ( 3.2 cm ) hailstones . The larger size hail- stones produced progressively larger ...
... specimens were also exposed to 11 / 4 - in dentations were made in the shingles by the ( 3.2 cm ) hailstones . Only small , superficial in- 114 - in ( 3.2 cm ) hailstones . The larger size hail- stones produced progressively larger ...
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15 cents air gun apparatus Applied Technology areas of different Asbestos cement asphalt flood coat Asphalt Roofing asphalt shingles automatic data processing building damage Building Research Building Science Series Built-up roofs Bureau of Standards Cement and Concrete Center Class C shingle Coal tar Concrete Properties cracking cylinder dense decks dents DEPARTMENT OF COMMERCE diameter different vulnerability felt damage Fiberboard on 1-in Foamboard free-fall terminal velocity freezing ft 61 cm Gas cylinder Glass fiber insulation hail damage hail resistance hailstone carrier Hailstone Molds Hailstorms ice spheres indentation Institute for Applied interply asphalt Interrelations Between Cement Joules kg/m² kg/m³ large hailstones launcher lb/sq Meteorol microswitches National Bureau Nonbituminous Roofing organic felt polyethylene Portland Cement prepared roofings reported Resistance of Roofing resistant to hail shingles showed Sidney H sizes of hailstones slag solidly supported areas specimen steel decking substrates tested Type 235 shingles U.S. DEPARTMENT U.S. Government Printing velocity 9 ст