How To Achieve 1 Hour Fire Rated Wood Roof Trusses

Gypsum wallboard roof ceilings wood framing pitched roof truss 11 1 hr.

How to achieve 1 hour fire rated wood roof trusses.

See full report for details. 276 fire rated ceiling assemblies suspension ceiling designs floor ceiling designs a003 3 hr. 2 x 8 f d joists 16 o c 1 layer 3 4 bead board ceiling span 17 18 live load 40 lbs. 3 4 fr 83 12 x 12 z runners fluorescent type none 2 1 2 concrete.

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. How do i get a 1 hour fire rating for the truss. 12 x 24 2 x 4 8 w10 x 25 beam floor units and beam support 3 hr. Screw fastened perpendicular to lower chord of wood trusses of 2 x 4 38 mm x 89 mm.

Concrete with cellular steel 3 hr. There is a truss directly above the firewall. Ibc table 721 3 item 21 1 1 describes a single prescriptive 1 hour rated floor or roof assembly that includes wood trusses. Any help is appreciated.

Assemblies include ducts dampers lighting or other fixtures in the tested assembly. By code i need a minimum 1 2 hour rating. Ul u338 figure 17 3 3. Applied to bottom chord of each truss floor or roof 1 hour.

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. 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. Chapter 3 of ansi tpi 1 stipulates that lumber treated with fire retardant chemicals must be identified and clearly marked by the manufacturer. Urb concealed grid system and tile.

And 12 of r 38 fiberglass batt insulation. Wood joists wood i joists floor trusses and flat or pitched roof trusses spaced a maximum 24 o c. Substrate roof floor ceiling time assembly ff file no. 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.

Type x gypsum board is wallboard to which non combustible fibers have been added. 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. 2x4 studs spaced 24 o c. I have a 1 hour firewall for both directions.