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
... stones ( ice spheres ) of various sizes were shot at roof assemblies at their free - fall terminal velocities . Indentations , granule loss and roofing fracture were observed . The following conclusions have been made from these results ...
... stones ( ice spheres ) of various sizes were shot at roof assemblies at their free - fall terminal velocities . Indentations , granule loss and roofing fracture were observed . The following conclusions have been made from these results ...
Page 3
... stones " of various sizes , cast the " hailstones " to approximate spheres more closely and explore areas of different vulnerability on various roof- ing systems . The work was primarily directed at bituminous roofing materials , but a ...
... stones " of various sizes , cast the " hailstones " to approximate spheres more closely and explore areas of different vulnerability on various roof- ing systems . The work was primarily directed at bituminous roofing materials , but a ...
Page 5
... ( 29.80 ) 212 ( 6.4 ) 117 80 ( 35.7 ) 53 ( 71.9 ) ( 7.0 ) 124 85 ( 37.8 ) 81 ( 109.8 ) 3 ( 7.6 ) 130 88 ( 39.6 ) 120 ( 162.7 ) Read from graphs in reference [ 9 ] . All of the results reported are based on hail- stones 5.
... ( 29.80 ) 212 ( 6.4 ) 117 80 ( 35.7 ) 53 ( 71.9 ) ( 7.0 ) 124 85 ( 37.8 ) 81 ( 109.8 ) 3 ( 7.6 ) 130 88 ( 39.6 ) 120 ( 162.7 ) Read from graphs in reference [ 9 ] . All of the results reported are based on hail- stones 5.
Page 6
... stones of a given size traveling at velocities within 10 percent of the terminal velocities reported in table 1 for hailstones of that size . The results are reported under the types of roofing studied . 4.1 . Asphalt Shingles When ...
... stones of a given size traveling at velocities within 10 percent of the terminal velocities reported in table 1 for hailstones of that size . The results are reported under the types of roofing studied . 4.1 . Asphalt Shingles When ...
Page 7
... stone . While it is outside the province of this report to identify these heavy Class C and Class A shingles more specifically , the manufac- turers have been informed of how their indi- vidual products performed and the basic prin ...
... stone . While it is outside the province of this report to identify these heavy Class C and Class A shingles more specifically , the manufac- turers have been informed of how their indi- vidual products performed and the basic prin ...
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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