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IRC Section R2401 — Gypsum Wallboard Installation

Updated Apr 3, 2026

Specifies gypsum board thickness, fastening, and joint treatment.

Section R2401 requires gypsum board in interior finishes. Thickness 1/2 inch is standard for 16-inch joist spacing, 5/8 inch for 24-inch spacing. Fastening with drywall screws spaced 12 inches on center prevents buckling. Joint compound fills seams with minimum three coats. Tape bridging seams prevents cracking. Moisture-resistant (greenboard) is used in bathrooms. Fire-rated (Type X) board has glass fiber for improved fire performance.

TAGS

irc gypsum-board interior-finishes

DETAILS

section

R2401

category

Interior Finishes

code body

IRC

code year

2021

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