5/8” (15.9 mm) ToughRock® Fireguard C® or 5/8” (15.9 mm) DensArmor Plus® Fireguard C gypsum panels applied perpendicular to resilient channels 16″ o.c. (12″ o.c. when insulation is draped over channels) with 1″ Type S screws 8″ o.c. Gypsum panels secured with 1” (25 mm) long Type S bugle head steel screws. Screws spaced 1/2” (12.7 mm) and 6” (152 mm) from side joints and 12” (305 mm) o.c. in the rest of the field. Screws spaced 3” (76 mm) from the stud joints. End joints secured to both resilient channels. Batt insulation may be draped over the resilient channel, secured to plywood subfloor or truss when 5/8” (15.9mm) ToughRock Fireguard C gypsum board are used. Insulation must be secured to plywood subfloor or trusses when DensArmor Plus Fireguard C gypsum panel is used.