1 Hour Roof Over Hang Protection

Ibc section 703 3 item 2.

1 hour roof over hang protection.

Prescriptive designs ibc table 721 3 item 21 1 1 describes a single prescriptive 1 hour rated floor or roof assembly that includes wood trusses. Hi all we need to provide one hour rated protection for under eaves on a residential property remodel. Roof ceiling and attic separation. Eave overhang fire protection.

The irc in table r302 1 1 only. An overhang protects the upper portion of the wall that it is attached to from rainfall and it also shades the windows under it from the sun. Use flat horizontal soffits see figure 3 instead of attaching the soffits to the sloped joists which creates sloped soffits. The ibc in section 705 2 3 permits the use of type iv construction fire retardant treated wood or 1 hr fire resistance construction for combustible projections.

The existing open eaves have t g sheathing with exposed rafter tails and 2x blocking b w rafters. Walls less than 5 feet from the property lot line must be of a listed hour fire1 resistant construction. The ibc provides options while the irc has only one method of compliance. However a garage located within 2 of the property line is permitted to have a 4 inch roof eave projection.

To the closest interior lot line. 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. To an imaginary line between two buildings on the lot. Overhangs such as roof eaves and soffits are one element needing protection.

To the centerline of a street an alley or public way. Wall framing whichever is closer to one of the following. Overhangs can be open in which the trusses rafters and decking are exposed see figure 1 or enclosed by a soffit. Roof overhangs must have a one hour fire protection on the underside when less than 5 from the property line and cannot project closer than 2 from the line.

Madesign history contact. Soffits a soffit encloses the underside of sloped or flat roof overhangs.