UL L1542-hr Fire RatingRoof/CeilingLoad-Bearing
Steel JoistGypsum BoardFiberglass BattDesign
Steel Truss Roof/Ceiling — 2 layers 5/8" Type X gypsum board
UL-listed 2-hour fire-rated steel truss roof/ceiling assembly. Steel bar joists at 48" o.c. with R-30 fiberglass batt, 2 layers of 5/8" Type X gypsum board on furring channels ceiling, 20 ga. steel deck.
Cross-Section Diagram
Legend
1Roof covering(varies)
220 ga. steel deck(varies)
3Steel bar joists at 48" o.c.(12"-24")
4R-30 fiberglass batt
55/8" Type X gypsum board on furring channels(5/8")
65/8" Type X gypsum board on furring channels(5/8")
Specifications
Fire Rating
2-Hour
Load Bearing
Yes
Total Thickness
15.25"
Applicable Codes
IBC 2021 Table 722.1
Construction Summary
Steel bar joists at 48" o.c. with R-30 fiberglass batt, 2 layers of 5/8" Type X gypsum board on furring channels ceiling, 20 ga. steel deck
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.