2308.6.8.3 Stepped footings in Seismic Design Categories B, C and D.
BC § 2308.6.8.3
In Seismic Design Categories B, C and D, where the height of a required braced wall panel extending from foundation to floor above varies more than 4 feet (1219 mm), the following construction shall be used: 1. Where the bottom of the footing is stepped and the lowest floor framing rests directly on a sill bolted to the footings, the sill shall be anchored as required in Section 2308.3.
2.Where the lowest floor framing rests directly on a sill bolted to a footing not less than 8 feet (2438 mm) in length along a line of bracing, the line shall be considered to be braced. The double plate of the cripple stud wall beyond the segment of footing extending to the lowest framed floor shall be spliced to the sill plate with metal ties, one on each side of the sill and plate. The metal ties shall be not less than 0.058 inch (1.47 mm) (16 galvanized gage) by 1 1/2 inches (38 mm) in width by 48 inches (1219 mm) with eight 16d common nails on each side of the splice location (see Figure 2308.6.8.3). The metal tie shall have a yield stress not less than 33,000 psi (227 MPa).
3.Where cripple walls occur between the top of the footing and the lowest floor framing, the bracing requirements for a story shall apply. For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm. Figure 2308.6.8.3Stepped Footing Connection Details
