IBC Design 721.1(2) 15-1.2
1-Hour Fire Rated Exterior or interior walls — 2" x 4" wood studs 16" on center with metal lath and 3/4" cement…
IBC Table 721.1(2), Item 15-1.2 (l, m) (Exterior or interior walls): 2" x 4" wood studs 16" on center with metal lath and 3/4" cement plaster on each side. Lath attached with 6d common nails 7" on center driven to 1" minimum penetration and bent over. Plaster mix 1:4 for scratch coat and 1:5 for brown coat, by volume, cement to sand. Minimum finished thickness (face-to-face) — 1-hr: 5-3/8". Prescriptive assembly from the adopted building code — thicknesses are code minimums, see table footnotes for conditions.
2" x 4" wood studs 16" on center with metal lath and 3/4" cement plaster on each side. Lath attached with 6d common nails 7" on center driven to 1" minimum penetration and bent over. Plaster mix 1:4 for scratch coat and 1:5 for brown coat, by volume, cement to sand.
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- Layer-by-layer components with thicknesses
- Cross-section diagram
- Applicable code sections and test standard
- 6 related assemblies