UL W1171-hr Fire RatingFloor/CeilingLoad-BearingSTC 57
Wood JoistFiberglass BattHigh STCDesign
Wood Joist Floor/Ceiling — single layer 5/8" Type C gypsum board
UL-listed 1-hour fire-rated wood joist floor/ceiling assembly. 2x12 wood joists at 16" o.c. with R-30 fiberglass batt, single layer of 5/8" Type C gypsum board ceiling.
Cross-Section Diagram
Legend
1Floor covering(varies)
23/4" OSB subfloor(3/4")
32x12 wood joists at 16" o.c.(11.25")
4R-30 fiberglass batt
55/8" Type C gypsum board(5/8")
Specifications
Fire Rating
1-Hour
STC Rating
STC 57
Load Bearing
Yes
Total Thickness
13.38"
Applicable Codes
IBC 2021 §722
Construction Summary
2x12 wood joists at 16" o.c. with R-30 fiberglass batt, single layer of 5/8" Type C gypsum board ceiling
Material Layers
Important Notice
This assembly listing is for reference only. Always verify against the current UL Product iQ database before specifying in construction documents. Material substitutions may void the fire rating. Consult with a qualified fire protection engineer for project-specific requirements.