How To Achieve 1 Hour Fire Rated Wood Roof Trusses

Type x gypsum board is wallboard to which non combustible fibers have been added.

How to achieve 1 hour fire rated wood roof trusses.

With 1 2 wood structural panels with exterior glue applied at right angles to top of joist or top chord of trusses. Wood joists wood i joists floor trusses and flat or pitched roof trusses spaced a maximum 24 o c. And 12 of r 38 fiberglass batt insulation. Applied to bottom chord of each truss floor or roof 1 hour.

Concrete with cellular steel 3 hr. There is a truss directly above the firewall. 2 x 8 f d joists 16 o c 1 layer 3 4 bead board ceiling span 17 18 live load 40 lbs. 276 fire rated ceiling assemblies suspension ceiling designs floor ceiling designs a003 3 hr.

Gypsum wallboard roof ceilings wood framing pitched roof truss 11 1 hr. 2x4 studs spaced 24 o c. Assemblies include ducts dampers lighting or other fixtures in the tested assembly. Substrate roof floor ceiling time assembly ff file no.

See full report for details. Fire rated suspended ceiling wood truss council of america floor or roof fire notes 1. Urb concealed grid system and tile. Chapter 3 of ansi tpi 1 stipulates that lumber treated with fire retardant chemicals must be identified and clearly marked by the manufacturer.

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. I have a 1 hour firewall for both directions. By code i need a minimum 1 2 hour rating.

Ibc table 721 3 item 21 1 1 describes a single prescriptive 1 hour rated floor or roof assembly that includes wood 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. 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. 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.

Any help is appreciated. 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. 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. 3 4 fr 83 12 x 12 z runners fluorescent type none 2 1 2 concrete.