IBC Design 721.1(2) 15-1.10

2-Hour Fire Rated Exterior or interior walls — Steel studs 0.060" thick, 4" deep or 6" at 16" or 24" centers, with…

IBC Table 721.1(2), Item 15-1.10 (Exterior or interior walls): Steel studs 0.060" thick, 4" deep or 6" at 16" or 24" centers, with 1/2" glass fiber-reinforced concrete (GFRC) on the exterior surface. GFRC is attached with flex anchors at 24" on center, with 5" leg welded to studs with two 1/2"-long flare-bevel welds, and 4" foot attached to the GFRC skin with 5/8"-thick GFRC bonding pads that extend 2-1/2" beyond the flex anchor foot on both sides. Interior surface to have two layers of 1/2" Type X gypsum wallboard (e). The first layer of wallboard to be attached with 1"-long Type S buglehead screws spaced 24" on center and the second layer is attached with 1-5/8"-long Type S screws spaced at 12" on center. Cavity is to be filled with 5" of 4 pcf (nominal) mineral fiber batts. GFRC has 1-1/2" returns packed with mineral fiber and caulked on the exterior. Minimum finished thickness (face-to-face) — 2-hr: 6-1/2". Prescriptive assembly from the adopted building code — thicknesses are code minimums, see table footnotes for conditions.