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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Page 1
... tend to be the most resistant to hail damage . ( d ) Heavier shingles tend to be more hail - resistant than Type 235 shingles . ( e ) Weathering tends to lower the hail resistance of asphalt shingles . ( f ) Built - up roofs on dense ...
... tend to be the most resistant to hail damage . ( d ) Heavier shingles tend to be more hail - resistant than Type 235 shingles . ( e ) Weathering tends to lower the hail resistance of asphalt shingles . ( f ) Built - up roofs on dense ...
Page 3
... tends to drop its hailstones at about 6000 ft . Figure 1 is a map of the central United States showing the distribution of storms during the years 1960-1966 in which at least $ 5000 worth of building damage was done by hail in each ...
... tends to drop its hailstones at about 6000 ft . Figure 1 is a map of the central United States showing the distribution of storms during the years 1960-1966 in which at least $ 5000 worth of building damage was done by hail in each ...
Page 5
... tend to fall within the narrow limits of ice spheres falling at about their free - fall terminal velocity [ 9 ] . The density of large hailstones has been shown to approximate that of solid ice [ 10 ] and seems to range between 0.89 and ...
... tend to fall within the narrow limits of ice spheres falling at about their free - fall terminal velocity [ 9 ] . The density of large hailstones has been shown to approximate that of solid ice [ 10 ] and seems to range between 0.89 and ...
Page 6
... tend to undergo a number of physical changes , which may affect their resistance to hail . A number of shingles that had been exposed on 1 / 2 - in ( 1.3 cm ) plywood to the weather in Washington , D. C. for 912 years became available ...
... tend to undergo a number of physical changes , which may affect their resistance to hail . A number of shingles that had been exposed on 1 / 2 - in ( 1.3 cm ) plywood to the weather in Washington , D. C. for 912 years became available ...
Page 7
... tend to be more resistant to hail dam- age at higher temperatures . It is fortunate that hailstorms occur in warm ... tends to be more brittle than asphalt and would be expected to respond to the hail impact as a brittle material . The ...
... tend to be more resistant to hail dam- age at higher temperatures . It is fortunate that hailstorms occur in warm ... tends to be more brittle than asphalt and would be expected to respond to the hail impact as a brittle material . The ...
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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