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IRC R403 — Footings

Updated Mar 26, 2026
Foundation footing requirements: minimum 12" wide for 1-story, 15" for 2-story, 18" for 3-story. Minimum depth below undisturbed ground. Frost depth per Table R301.2. Reinforcement for seismic and high-wind zones.
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IRCfootingfoundationfrost-depthresidential
DETAILS
section
R403
category
IRC — Foundations
code body
IRC
code year
2024
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