UL W1144-hr Fire RatingFloor/CeilingLoad-BearingSTC 54
Wood JoistMulti-Layer GypsumDesign
Wood Joist Floor/Ceiling — 4 layers 5/8" Type X gypsum board
UL-listed 4-hour fire-rated wood joist floor/ceiling assembly. 2x10 wood joists at 16" o.c., 4 layers of 5/8" Type X gypsum board ceiling.
Cross-Section Diagram
Legend
1Floor covering(varies)
23/4" plywood subfloor(3/4")
32x10 wood joists at 16" o.c.(9.25")
45/8" Type X gypsum board(5/8")
55/8" Type X gypsum board(5/8")
65/8" Type X gypsum board(5/8")
75/8" Type X gypsum board(5/8")
Specifications
Fire Rating
4-Hour
STC Rating
STC 54
Load Bearing
Yes
Total Thickness
13.25"
Applicable Codes
IBC 2021 Table 722.1IBC 2024 Table 722.1
Construction Summary
2x10 wood joists at 16" o.c., 4 layers of 5/8" Type X 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.