UL Design V320
2-Hour Fire Rated Mass Timber —
TESTED assembly (UL certified design V320, cited in the WoodWorks Inventory of Fire Resistance-Tested Mass Timber Assemblies). Load-bearing wall of 5-ply, 175 mm (6-7/8 in) Nordic E1 CLT with panel-to-panel half-lap joints, protected on both sides with one layer of 5/8 in Type C or Type X gypsum board, achieving a 2-hour rating with axial load limited to 30% of allowable compression parallel to grain. The same UL V320 design lists the identical 175 mm panel unprotected at 1 hour.
TESTED assembly (UL certified design V320, cited in the WoodWorks Inventory of Fire Resistance-Tested Mass Timber Assemblies). Load-bearing wall of 5-ply, 175 mm (6-7/8 in) Nordic E1 CLT with panel-to-panel half-lap joints, protected on both sides with one layer of 5/8 in Type C or Type X gypsum…
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- Layer-by-layer components with thicknesses
- Cross-section diagram
- Applicable code sections and test standard
- 6 related assemblies