IBC Design 721.1(2) 13-1.1

1-Hour Fire Rated Noncombustible studs—interior partition with gypsum wallboard each side — 0.018" (No. 25 carbon sheet steel gage) channel-shaped studs 24" on…

IBC Table 721.1(2), Item 13-1.1 (Noncombustible studs—interior partition with gypsum wallboard each side): 0.018" (No. 25 carbon sheet steel gage) channel-shaped studs 24" on center with one full-length layer of 5/8" Type X gypsum wallboard (e) applied vertically attached with 1"-long No. 6 drywall screws to each stud. Screws are 8" on center around the perimeter and 12" on center on the intermediate stud. Where applied horizontally, the Type X gypsum wallboard shall be attached to 3-5/8" studs and the horizontal joints shall be staggered with those on the opposite side. Screws for the horizontal application shall be 8" on center at vertical edges and 12" on center at intermediate studs. Minimum finished thickness (face-to-face) — 1-hr: 2-7/8 (d)". Prescriptive assembly from the adopted building code — thicknesses are code minimums, see table footnotes for conditions.