How To Achieve 1 Hour Fire Rated Wood Roof Trusses

276 fire rated ceiling assemblies suspension ceiling designs floor ceiling designs a003 3 hr.

How to achieve 1 hour fire rated wood roof trusses. Concrete with cellular steel 3 hr. Any help is appreciated. Substrate roof floor ceiling time assembly ff file no. Chapter 3 of ansi tpi 1 stipulates that lumber treated with fire retardant chemicals must be identified and clearly marked by the manufacturer.

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. Gypsum wallboard roof ceilings wood framing pitched roof truss 11 1 hr. Ibc table 721 3 item 21 1 1 describes a single prescriptive 1 hour rated floor or roof assembly that includes wood trusses. 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.

2 x 8 f d joists 16 o c 1 layer 3 4 bead board ceiling span 17 18 live load 40 lbs. There is a truss directly above the firewall. With 1 2 wood structural panels with exterior glue applied at right angles to top of joist or top chord of trusses. Assemblies include ducts dampers lighting or other fixtures in the tested assembly.

Fire rated suspended ceiling wood truss council of america floor or roof fire notes 1. According to the book commercial drafting and detailing a typical one hour fire rated wall consists of 2x4 studs spaced 16 inches from the center of one stud to the center of the next covered by 5 8 inch type x gypsum board. Ul u338 figure 17 3 3. Wood joists wood i joists floor trusses and flat or pitched roof trusses spaced a maximum 24 o c.

Screw fastened perpendicular to lower chord of wood trusses of 2 x 4 38 mm x 89 mm. Type x gypsum board is wallboard to which non combustible fibers have been added. Urb concealed grid system and tile. How do i get a 1 hour fire rating for the truss.

See full report for details. Applied to bottom chord of each truss floor or roof 1 hour. I have a 1 hour firewall for both directions. 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.

12 x 24 2 x 4 8 w10 x 25 beam floor units and beam support 3 hr. 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. 3 4 fr 83 12 x 12 z runners fluorescent type none 2 1 2 concrete. By code i need a minimum 1 2 hour rating.