Quantcast
Fire Rated System Design - ULC W423 or UL U425
Print This Page

ULC W423 or UL U425

Interior Partitions - Steel Stud (non-load-bearing)

Fire Rating

1 hour

STC

49 USG-810940

Assembly thickness

203 mm (8")

Gypsum Board - 12.7 mm (1/2 in.) thick gypsum board applied horizontally or vertically
Gypsum Board - 12.7 mm (1/2 in.) thick gypsum board applied horizontally or vertically
Steel Studs - 152.4 mm (6 in.) 0.8 mm (20) ga. steel stud spaced max. 610 mm (24 in.) OC
Batts and Blankets - 50.8 mm (2 in.) mineral wool batt insulation
Gypsum Board - 12.7 mm (1/2 in.) thick gypsum board applied horizontally or vertically
Gypsum Board - 12.7 mm (1/2 in.) thick gypsum board applied horizontally or vertically
  • Gypsum Board - 12.7 mm (1/2 in.) thick gypsum board applied horizontally or vertically
  • Gypsum Board - 12.7 mm (1/2 in.) thick gypsum board applied horizontally or vertically
  • Steel Studs - 152.4 mm (6 in.) 0.8 mm (20) ga. steel stud spaced @ max. 610 mm (24 in.) OC - 600S125-30
  • Batts and Blankets - 50.8 mm (2 in.) mineral wool batt insulation
  • Gypsum Board - 12.7 mm (1/2 in.) thick gypsum board applied horizontally or vertically
  • Gypsum Board - 12.7 mm (1/2 in.) thick gypsum board applied horizontally or vertically

Stud size is minimum unless otherwise stated in design.  
For the most up-to-date information refer to the UL/ULC Fire resistance directory U425 · ULC W423 ·