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Home / Assemblies / UL X121
UL X1214-hr Fire RatingBeamLoad-Bearing
Structural SteelDesign

Steel Beam — Gypsum board enclosure

UL-listed 4-hour fire-rated steel beam assembly. W-shape steel beam with Gypsum board enclosure, 4-hour fire rating.

Cross-Section Diagram

12BEAM PROTECTIONSECTION · NOT TO SCALE2 LAYERSsee legend for ① ② ③
Legend
1W-shape steel beam(16")
2Gypsum board enclosure(2.19")

Specifications

Fire Rating
4-Hour
Load Bearing
Yes
Total Thickness
20.38"
Source / Publisher
UL (Underwriters Laboratories)
Design Number
X121
Assembly Type
Beam
Test Standard
CAN/ULC-S101
Construction Group
Non-Combustible
Number of Layers
2 layers

Applicable Codes

NFPA 5000IBC 2021 §722

Construction Summary

W-shape steel beam with Gypsum board enclosure, 4-hour fire rating

Material Layers

LayerMaterialThickness
1W-shape steel beam16"
2Gypsum board enclosure2.19"

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.