1406.4.2 Appendages on Type III, IV and VA construction.
BC § 1406.4.2
Appendages on buildings of Type III, IV and VA construction may be constructed of combustible materials, provided that all the following conditions are met: 1. Such building does not exceed three stories or 40 feet (12 192 mm) in height, whichever is less.
2.The main use or dominant occupancy of such building is classified in Occupancy Group R-2 or R-3.
3.The appendage has an exterior separation on all exposed sides of at least 15 feet (4572 mm), measured from the outermost surface of the appendage, except that appendages with exposed sides protected by minimum 1-hour fire-rated construction extending at least 36 inches (914.4 mm) above the highest combustible horizontal surface may be located up to a minimum distance of 36 inches (914.4 mm) from any property line.
4.The appendage is so constructed that its removal or destruction will not reduce the structural stability or fire-resistive integrity of the building.
5.The appendage has a superficial area not exceeding 150 square feet (13.9 m 2 ) when viewed from directly above and is included in the area limitations of Table 503* for the entire building. * Editor's note: As set forth in L.L. 2021/126; Table 503 was deleted by L.L. 2021/126.
6.The appendage is not higher than the sills of the second-story windows.
7.The vertical surface area of the combustible portions of the appendage does not exceed 10 percent of the total wall area (windows excluded) of the building.
8.For enclosed appendages, the roof of the appendage has a class A roof covering, and the soffit or ceiling covering the combustible roof framing shall have a minimum 1-hour fire-resistance rating. Exception: Appendages constructed of fire-retardant-treated wood, on buildings not exceeding 3 stories or40 feet (12 192 mm) in height, whichever is less, need not comply with Items 2 through 8.
