Wind resistances of asphalt shingles are one of the primary
performance considerations that should be evaluated when specifying
asphalt shingle products. Recent changes to wind-load design
procedures have resulted in a need for designers to reconsider how
to specify asphalt shingles' wind resistances.
Since the early 1970s, asphalt shingles' wind resistances have
been tested according to a fan-induced wind test method described
in ASTM D3161, "Standard Test Method for Wind-Resistance of Asphalt
Shingles (Fan-Induced Method)." With this test method, asphalt
shingle products are classified as Class A, D or F, which represent
maximum test velocities of 60 mph, 90 mph or 110 mph,
respectively.
UL 997, "Wind Resistance of Prepared Roof Covering Materials,"
is a test method similar to ASTM D3161 with similar...
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