Typical assembly (not a tested listing)

1-Hour Fire Rated Wood Truss Roof/Ceiling — single layer 5/8" Type C gypsum board

Typical 1-hour fire-rated wood truss roof/ceiling assembly. Wood trusses at 24" o.c. with R-38 blown fiberglass, single layer of 5/8" Type C gypsum board ceiling, 7/16" OSB 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.

Wood trusses at 24" o.c. with R-38 blown fiberglass, single layer of 5/8" Type C gypsum board ceiling, 7/16" OSB sheathing

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  • Layer-by-layer components with thicknesses
  • Cross-section diagram
  • Applicable code sections and test standard
  • 6 related assemblies
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