UL W1191.5-hr Fire RatingFloor/CeilingLoad-BearingSTC 39
Wood JoistMineral WoolDesign
Wood Joist Floor/Ceiling — single layer 5/8" Type C gypsum board
UL-listed 1.5-hour fire-rated wood joist floor/ceiling assembly. 2x12 wood joists at 16" o.c. with R-30 mineral wool, single layer of 5/8" Type C gypsum board ceiling.
Cross-Section Diagram
Legend
1Floor covering(varies)
23/4" plywood subfloor(3/4")
32x12 wood joists at 16" o.c.(11.25")
4R-30 mineral wool
55/8" Type C gypsum board(5/8")
Specifications
Fire Rating
1.5-Hour
STC Rating
STC 39
Load Bearing
Yes
Total Thickness
13.38"
Applicable Codes
IRC R302.1
Construction Summary
2x12 wood joists at 16" o.c. with R-30 mineral wool, 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.