- Author
-
Greenfeld, S. H.
- Title
- Hail Resistance of Roofing Products. Building Science Series.
- Coporate
- National Bureau of Standards, Washington, D.C. Building Research Div.
- Report
-
NBS BSS 023
August 1969
- Keywords
-
hail, impact shock; roofs, damage; construction materials; shock resistance; deformation; wear resistance; cracks; vulnerability; asphalt; substrates; asbestos; design; deterioration; test methods
- Identifiers
- roofing; shingles; weathering; indentation; felts; slate; tiles; metal sheets; aggregates
- Abstract
- 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 velocities. 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)