One Hour Fire Rated Roof Assembly

Table 1 one hour fire rated loadbearing wood frame wall assemblies.

One hour fire rated roof assembly.

With 1 2 wood structural panels with. The following tables are only summaries of the fire rated assembly reports. Fire resistance ratings time temperature include structural elements and everything above including the roof membrane and its surfacing. Wood joists wood i joists floor trusses and flat or pitched roof trusses spaced a maximum 24 o c.

According to the engineered wood association a one hour rating indicates that a wall constructed in a manner similar to the one tested will contain flames and high temperatures and support its full load for at least one hour after the fire begins. 3 mineral wool batts. Truss technology in building figure 1. Elements of buildings the fire resistance rating classifies the ability of an assembly to confine and isolate fire within a zone comprised of fire resistance rated walls ceiling and floor assemblies.

Sheathing on both sides. 2x4 16 o c. Usg provides resources here for our ul wall assemblies for seamless integration into any construction project. Ibc table 721 3 item 21 1 1 describes a single prescriptive 1 hour rated floor or roof assembly that includes wood trusses.

Users must consult the listed agency s documentation for complete information. Generic fire rated assembly listing construction elements 1 5 hr rating 1. 2 fire rated wood frame wall and floor ceiling assemblies. 5 8 type x gypsum wallboard h 2 6 type s drywall screws 12 o c.

Assemblies rated from both sides. Test reports are available from reporting agencies or wtca where indicated. These wall assembly files are used for planning and estimation purposes for many ul wall types such as fire rated wall assemblies. If trusses are specified then these assemblies can be used to achieve the desired fire rating as long as all the details of the assembly requirements are met.

Keep in mind that most of the wood truss fire rated assemblies call for a minimum depth of 12 in. The ratings relate to fire tests designed to determine how quickly fire can raise the temperature to unacceptable levels. A one hour rating would mean the structural elements have not yet reached their yield point when exposed to a under deck heat load defined in astm e119 for steel structural members as reaching 1 070 degrees f.