Cost Saving Firewalls

BXUV.U382
Fire Resistance Ratings - ANSI/UL 263

Design No. U382
December 27, 2007

Bearing wall rating — 2-1/2 Hr. or 3 Hr. (See item 3A)

1. Wood Studs — Double row of nominal 2 x 4 in. studs, spaced 16 in. OC and cross-braced at mid-height. Opposite rows spaced 1 in. apart, staggered 8 in. OC and joined at the top and bottom with bearing plates.

2. Bearing Plates — (not shown) — Nominal 2 x 4 in. Two layers on top and one layer on bottom for each row of studs.

3. Wallboard, Gypsum* — One layer of 4 ft wide. 5/8 in. thick gypsum wallboard applied vertically and nailed to studs and bearing plates 7 in. OC with 6d cement coated nails, 1-7/8 in. long, 0.0915 in. shank diameter and 1/4 in. diameter head. Gypsum wallboard joints centered over studs.

UNITED STATES GYPSUM CO — Type C

3A. Wallboard, Gypsum* — Two layers of 5/8 inch thick, 4 ft wide gypsum wallboard applied vertically, with the first layer of gypsum board attached with 6d cement coated nails spaced 10 in. OC., and the second layer of gypsum board attached with 8d nails spaced 7 in. OC. Vertical joints between 1st and 2nd layer of wallboard are to be staggered.

UNITED STATES GYPSUM CO — Type C

4. Joints and Screw Heads — (Not shown) — Wallboard joints taped and both joints and nailheads covered with joint compound.

5. Fiber, Sprayed* — Spray applied cellulose material. The fiber is applied with water to completely fill the enclosed 8 in. cavity in accordance with the application instructions supplied with the product. The minimum dry density is 4.58 lbs/ft3.