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IRC Section R1004 — Stairways

Updated Apr 3, 2026

Establishes residential stairway dimensions and safety requirements.

Section R1004 provides riser and tread dimensions for residential stairs. Riser height 7-7.75 inches with uniform steps prevents trips. Tread depth 10-11 inches provides comfortable stepping. Handrails on at least one side are required for stairs with more than three steps. Guardrails 36 inches high with balusters spaced 4 inches apart prevent falls. Stairway width minimum 36 inches accommodates movement.

TAGS

irc stairs residential

DETAILS

section

R1004

category

Means of Egress

code body

IRC

code year

2021

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