Seismic Design Category (SDC) is defined in ASCE 7-22. Most of Salt Lake, Utah, Davis, and Weber Counties are SDC D — the second-highest level — reflecting the significant ground motion hazard of the Wasatch Fault. SDC D requires: concrete reinforcing per ACI 318 Chapter 18 seismic provisions (heavier rebar, tighter spacing, special lap splice and hook details at all critical sections); anchor bolts designed for seismic uplift and lateral shear forces rather than gravity loads alone; continuous hold-down hardware at shear wall locations; and special inspection of reinforcing placement on qualifying structures. These requirements substantially exceed standard residential construction minimums in many jurisdictions. RainFire Builders designs every Wasatch Front foundation to SDC D — whether or not the local permit office would require it for a given project type.