5/8” (15.9 mm) ToughRock® Fireguard X® (per UL U421 only)Products or 5/8” (15.9 mm) DensArmor Plus® Fireguard® gypsum panels applied vertically or horizontally to one side of 2-1/2” (64 mm), 25-gauge (18 mils) steel studs 24” (610 mm) o.c. with 1” (25.4 mm) Type S drywall screws 8” (203 mm) o.c. at vertical joints and 12” (305 mm) o.c. at intermediate studs when applied vertically to framing, or 8” (203 mm) o.c. when applied horizontally to framing. Opposite side: Base layer – 5/8” (15.9 mm) ToughRock® Fireguard X® (per UL U421 only)Products or 5/8” (15.9 mm) DensArmor Plus Fireguard gypsum panels applied vertically or horizontally to studs with 1” (25.4 mm) Type S drywall screws 8” (203 mm) o.c. at vertical joints and 12” (305 mm) o.c. at intermediate studs when applied vertically to framing, or 8” (203 mm) o.c. when applied horizontally to framing. Second layer – 5/8” (15.9 mm) ToughRock® Fireguard X® (per UL U421 only)Products or 5/8” (15.9 mm) DensArmor Plus Fireguard gypsum panels applied vertically or horizontally to studs with 1-5/8” (41 mm) Type S drywall screws 12” (305 mm) o.c. Face layer – 5/8” (15.9 mm) ToughRock® Fireguard X® (per UL U421 only)Products or 5/8” (15.9 mm) DensArmor Plus Fireguard gypsum panels applied vertically or horizontally to studs with 2-3/8” (60 mm) Type S drywall screws 8” (203 mm) o.c. at vertical joints and 12” (305 mm) o.c. at intermediate studs when applied vertically to framing, or 8” (203 mm) o.c. applied horizontally to framing. Horizontal joints staggered not less than 6” (152 mm) between layers. When gypsum panels are other than 48” (1219 mm) wide, panels are applied horizontally to the framing. Vertical joints staggered 24” (610 mm) each layer and side. Sound tested with 2-1/2” (64 mm) fiberglass insulation. Non-load bearing.
