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IRC Section R801 — General Roof Requirements

Updated Apr 3, 2026

Establishes roof dead load, live load, and structural design requirements for residential roofs.

Section R801 specifies that residential roofs must be designed for dead load (permanent weight of materials), live load (snow or maintenance access), wind load, and seismic loads. Roof live load is typically 20 pounds per square foot for sloped roofs or flat roofs. Snow load varies by climate and is critical in cold regions. Wind load is determined from maps and building exposure. Roof-to-wall connections must resist uplift and lateral forces. Rafter spacing (typically 16 or 24 inches on center) and size are selected from tables based on span and load.

TAGS

irc roof residential

DETAILS

section

R801

category

Roof Assembly

code body

IRC

code year

2021

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