International Residential Code
SUBJECT: Attachment of Asphalt Shingles
CHANGE TYPE: Addition
R905.2.6 Attachment. Asphalt shingles shall have the minimum number of fasteners required by the manufacturer. For normal application, asphalt shingles
shall be secured to the roof with not less than
four fasteners per strip shingle or two fasteners per
individual shingle. Where the roof slope exceeds 20
units vertical in 12 units horizontal (167% slope),
special methods of fastening are required. For roofs
located where the basic wind speed per Figure
301.2(4) is 110 mph (49 m/s) or higher, special
methods of fastening are required. Special fastening
methods shall be tested in accordance with ASTM D
3161, modified to use a wind speed of 110 mph (177
km/h). Class F. Asphalt shingle wrappers shall bear
a label indicating compliance with ASTM D 3161 Class F.
Shingles classified using ASTM D 3161 are acceptable for use in wind zones less than 110 mph (49
m/s). Shingles classified using ASTM D 3161 Class F
are acceptable for use in all cases where special fastening
is required.
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CHANGE SIGNIFICANCE:There were no requirements in
the 2003 code for labeling of shingle wrappers containing
shingles that are intended for use in high-wind areas. In
regions with basic wind speeds of 110 miles per hour or
greater, building officials, consumers, roofers and suppliers had difficulty verifying that shingle products being used
were in fact approved for special fastening methods in accordance
with ASTM D3161, Class F. The language in the
2006 code requires that all such shingle wrappers be labeled
to indicate special fastening methods in accordance
with ASTM D3161, Class F. This eliminates confusion and
misapplication of shingles in high-wind regions. The last
paragraph, which provided clarification about where shingles
tested to ASTM D3161 could be used, was relocated
without any technical changes to Section R905.2.4.1.
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