IBC Design 721.1(2) 14-1.1

1-Hour Fire Rated Wood studs—interior partition with gypsum wallboard each side — 2" x 4" wood studs 16" on center with two layers of 3/8" regular…

IBC Table 721.1(2), Item 14-1.1 (h, m) (Wood studs—interior partition with gypsum wallboard each side): 2" x 4" wood studs 16" on center with two layers of 3/8" regular gypsum wallboard (e) each side, 4d cooler (n) or wallboard (n) nails at 8" on center first layer, 5d cooler (n) or wallboard (n) nails at 8" on center second layer with laminating compound between layers, joints staggered. First layer applied full length vertically, second layer applied horizontally or vertically. Minimum finished thickness (face-to-face) — 1-hr: 5". Prescriptive assembly from the adopted building code — thicknesses are code minimums, see table footnotes for conditions.