1 Hour Fire Rated Roof Overhang

Use flat horizontal soffits see figure 3 instead of attaching the soffits to the sloped joists which creates sloped soffits.

1 hour fire rated roof overhang.

Where when and how to determine if you need it. Ibc table 721 3 item 21 1 1 describes a single prescriptive 1 hour rated floor or roof assembly that includes wood trusses. Time temperature ratings the third major roof system fire test is astm e 119. Fire resistance rated 1 hour on the underside.

Fm calls their acceptable risk systems class 1 while ul calls theirs classified insulated metal deck constructions. This is a system test that includes structural members such as beams trusses and roof deck. Roof eave fire resistance rating shall be permitted to be reduced to 0 hours on the underside of the. Enclose overhangs with soffits that have a minimum 1 hour fire resistance rating to prevent embers and hot gases from making contact with the joists rafters or trusses or the underside of the roof decking.

Is required on the underside or. Wood joists wood i joists floor trusses and flat or pitched roof trusses spaced a maximum 24 o c. Overhangs one hour fire resistance rating. He was told that the walls would need to have a fire resistive construction and also the eave overhang would need to be rated 1 hour as well because it encroaches into the setback.

Ul and fm list many roof ceiling systems in their. The detail he gave us one coat stucco sub shows 2 layers of type x screwed into the rafter tails 3 5 8 with lath and stucco over that. Everything you wanted to know about fire rated construction but were afraid to ask. Enclose overhangs with soffits that have a minimum 1 hour fire resistance rating to prevent embers and hot gases from making contact with the joists rafters or trusses or the underside of the roof decking.