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Home / Assemblies / UL L107
UL L1072-hr Fire RatingRoof/CeilingLoad-Bearing
Wood JoistGypsum BoardDesign

Wood Truss Roof/Ceiling — 2 layers 5/8" Type C gypsum board

UL-listed 2-hour fire-rated wood truss roof/ceiling assembly. Wood trusses at 24" o.c. with R-49 blown cellulose, 2 layers of 5/8" Type C gypsum board ceiling, 5/8" plywood sheathing.

Cross-Section Diagram

123456ROOF/CEILING ASSEMBLYSECTION · NOT TO SCALE6 LAYERSsee legend for ① ② ③
Legend
1Roof covering(varies)
25/8" plywood sheathing(5/8")
3Wood trusses at 24" o.c.(12"-24")
4R-49 blown cellulose
55/8" Type C gypsum board(5/8")
65/8" Type C gypsum board(5/8")

Specifications

Fire Rating
2-Hour
Load Bearing
Yes
Total Thickness
15.25"
Source / Publisher
UL (Underwriters Laboratories)
Design Number
L107
Assembly Type
Roof/Ceiling
Test Standard
CAN/ULC-S101
Construction Group
Light Frame
Number of Layers
6 layers

Applicable Codes

IBC 2024 §722IBC 2021 Table 722.1

Construction Summary

Wood trusses at 24" o.c. with R-49 blown cellulose, 2 layers of 5/8" Type C gypsum board ceiling, 5/8" plywood sheathing

Material Layers

LayerMaterialThickness
1Roof coveringvaries
25/8" plywood sheathing5/8"
3Wood trusses at 24" o.c.12"-24"
4R-49 blown cellulose
55/8" Type C gypsum board5/8"
65/8" Type C gypsum board5/8"

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.