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IRC Section R804 — Roof Coverings and Assemblies

Updated Apr 3, 2026
Establishes wind resistance ratings and fire ratings for residential roof coverings.

Section R804 addresses residential roof coverings. Wind resistance ratings from ASTM testing classify materials into basic wind coverage (50 mph), high-wind coverage (90+ mph), and maximum coverage. Underlayment materials including felt, synthetic membranes, and specialized ice-and-water barriers protect the roof deck. Valleys where two slopes meet require reinforced flashing and underlayment. Ridge caps seal the ridge line where slopes meet. Penetrations for vents, chimneys, and utilities require flashing.

TAGS
ircroofingwind-resistance
DETAILS
section
R804
category
Roof Assembly
code body
IRC
code year
2021
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