Typical assembly (not a tested listing)
3-Hour Fire Rated Wood Truss Roof/Ceiling — 2 layers 5/8" Type X gypsum board
Typical 3-hour fire-rated wood truss roof/ceiling assembly. 2x10 wood rafters at 16" o.c. with R-49 blown cellulose, 2 layers of 5/8" Type X gypsum board ceiling, 5/8" plywood sheathing. Illustrative example of typical construction — not a tested UL or GA listing. Use a listed design (UL Product iQ or GA-600) for construction documents.
2x10 wood rafters at 16" o.c. with R-49 blown cellulose, 2 layers of 5/8" Type X gypsum board ceiling, 5/8" plywood sheathing
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- Layer-by-layer components with thicknesses
- Cross-section diagram
- Applicable code sections and test standard
- 6 related assemblies