How To Achieve 1 Hour Fire Rated Wood Roof Trusses

3 4 fr 83 12 x 12 z runners fluorescent type none 2 1 2 concrete.

How to achieve 1 hour fire rated wood roof trusses.

Substrate roof floor ceiling time assembly ff file no. 2x4 studs spaced 24 o c. 12 x 24 2 x 4 8 w10 x 25 beam floor units and beam support 3 hr. I need help to determine the fire rating of a ceiling unfinished attic space above with 1 2 gyp board with attached to wood trusses 24 o c.

Ibc table 721 3 item 21 1 1 describes a single prescriptive 1 hour rated floor or roof assembly that includes wood trusses. See full report for details. Concrete with cellular steel 3 hr. And 12 of r 38 fiberglass batt insulation.

There is a truss directly above the firewall. Screw fastened perpendicular to lower chord of wood trusses of 2 x 4 38 mm x 89 mm. I have a 1 hour firewall for both directions. How do i get a 1 hour fire rating for the truss.

Any help is appreciated. Urb concealed grid system and tile. Wood joists wood i joists floor trusses and flat or pitched roof trusses spaced a maximum 24 o c. Assemblies include ducts dampers lighting or other fixtures in the tested assembly.

Ul p533 roof ceiling one layer 5 8 15 9 mm fire shield c ga rc 2603 wallboard attached to 1 2 12 7 mm resilient furring channel spaced 12 o c. Ul u338 figure 17 3 3. Type x gypsum board is wallboard to which non combustible fibers have been added. By code i need a minimum 1 2 hour rating.

With 1 2 wood structural panels with exterior glue applied at right angles to top of joist or top chord of trusses. I believe adding 5 8 drywall on both sides is the answer but i don t have a design rating number or detail for it. 1 hour rated wall bearing or non bearing with optional insulation with a finish rating of 20 minutes for 1 layer of gypsum each side for non bearing walls or 59 minutes with 2 layers of gypsum each side for bearing walls on a single gable truss with 2x3 o c. 2 x 8 f d joists 16 o c 1 layer 3 4 bead board ceiling span 17 18 live load 40 lbs.

Chapter 3 of ansi tpi 1 stipulates that lumber treated with fire retardant chemicals must be identified and clearly marked by the manufacturer. Fire rated suspended ceiling wood truss council of america floor or roof fire notes 1. Gypsum wallboard roof ceilings wood framing pitched roof truss 11 1 hr. Requirements related to fire retardant materials specific to trusses are located in ansi tpi 1 design standard for the manufacture of metal plate connected wood trusses.