WIJ-1.2 One-Hour Fire-Resistive Ceiling Assembly
Floora/Ceiling - 100% Design Load - 1 Hour Rating - ASTM E 119 / NFPA 251

1. Floor Topping (optional, not shown): Gypsum concrete, lightweight or normal concrete topping.
2. Floor Sheathing: Minimum 23/32 inch thick tongue-and-groove wood sheathing (Exposure 1). Installed per code requirements with minimum 8d common nails, and glued to joist top flanges with AFG-01 construction adhesive.
3. Insulation: Minimum 1-1/2 inch thick mineral wool insulation batts – 2.5 pcf (nominal), supported by resilient channels.
4. Structural Members: Wood I-joists spaced a maximum of 24 inches on center.
      Minimum I-joist flange depth: 1-1/2 inches Minimum I-joist flange area: 5.25 inches2
      Minimum I-joist web thickness: 7/16 inch Minimum I-joist depth: 9-1/4 inches
     
Types of Adhesives Used in Tested I-Joists
Flange-to-Flange Endjoint Flange-to-Web Joint Web-to-Web Endjoint
Phenol-Resorcinol-Formaldehyde Phenol-Resorcinol-Formaldehyde Phenol-Resorcinol-Formaldehyde

5. Resilient Channels: Minimum 0.019 inch thick galvanized steel resilient channels, attached perpendicular to I-joists using 1-5/8 inch long drywall screws. Resilient channels spaced 16 inches on center and doubled at each wallboard end joint extending to the next joist.
6. Gypsum Wallboard: Minimum 5/8 inch thick Type C gypsum wallboard installed with long dimension perpendicular to resilient channels and fastened to each channel with minimum 1 inch long Type S drywall screws. Fasteners spaced 12 inches on center in the field of the wallboard, 8 inches on center at wallboard end joints, and 3/4 inches from panel edges and ends. End joints of wallboard staggered.
7. Finish System (not shown): Face layer joints covered with tape and coated with joint compound. Screw heads covered with joint compound.

      Fire Test conducted at Gold Bond Building Products Research Center June 19, 1984
      Third Party Witness: Warnock Hersey International, Inc. Report No: WHI-694-0159

STC and IIC Sound Ratings for Listed Assembly
Without Gypsum Concrete With Gypsum Concrete
Cushioned Vinyl Carpet & Pad Cushioned Vinyl Carpet & Pad
STC IIC STC IIC STC IIC STC IIC
51 b 46 b 51 b 64 b 60 b 50 b 60 b 65 b
a This assembly may also be used in a fire-rated roof/ceiling application, but only when constructed exactly as described.
b STC and IIC values estimated by David L. Adams Associates, Inc


Copyright © 2002, 2007
AMERICAN WOOD COUNCIL                       AMERICAN FOREST & PAPER ASSOCIATION, INC                                             February 2007