IBC Chapter 25 — Gypsum Board and Plaster

Updated Mar 26, 2026

Gypsum types (regular, Type X, Type C, moisture-resistant), fire assemblies, installation, plaster systems.

IBC Ch25: 5/8 Type X for 1-hr rated (per GA-600 fire assemblies). Screw spacing per GA-216. UL fire assemblies: U305 1-hr wood, U419 1-hr steel, U411 2-hr double layer. Level 4 finish: tape + 3 coats. Level 5: skim coat. Exterior sheathing: glass-mat (C1177) behind WRB.

TAGS

IBC gypsum drywall fire-resistance Type-X plaster

DETAILS

code year

2024

code section

Chapter 25

SOURCES

🔗https://codes.iccsafe.org/content/IBC2021P2

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