Base Layer: 5/8” (15.9 mm) ToughRock® Fireguard X® or DensArmor Plus® Fireguard® gypsum panels applied vertically or horizontally to one side of a double row of 2-1/2” (64 mm), 25-gauge steel studs 24” (610 mm) o.c. and not less than 1” (25.4 mm) apart with 1” (25.4 mm) Type S drywall screws 16” (406 mm) o.c. Face Layer: 5/8” (15.9 mm) ToughRock Fireguard X or DensArmor Plus Fireguard gypsum panels applied vertically or horizontally to same side of studs with 1-5/8” (41 mm) Type S drywall screws 12” (305 mm) o.c. Face layer vertical joints offset one stud cavity from base layer vertical joints. Face layer horizontal joints offset not less than 6” (152 mm) from base layer horizontal joints. Vertical joints centered over studs and staggered one stud cavity on opposite sides of studs. Horizontal joints need not be backed by framing. Horizontal joints on opposite sides need not be staggered. Lateral bracing on both sides of the wall not less than 5 feet on center vertically. Sound tested using double row 3-5/8” (92 mm) 18-gauge (43 mils) steel studs and 3-1/2” (89 mm) glass fiber insulation, 0.5 pcf, on both sides in cavity. (NLB)
