A footing on the coastal flats is built to hold together, not just to hold up. Most of the city south of Bolsa Avenue is mapped by the California Geological Survey as ground that can liquefy in an earthquake, loose wet sand that briefly stops bearing anything. The code's answer is a footing that acts as one beam, continuous around the plan with steel top and bottom and the corners tied, so an addition settles as a piece with the house rather than breaking away from it.
Goldenwest Huntington Beach Concrete has dug footings in Huntington Beach since 2017, under Scott Ferreira, who spent 19 years on foundation crews across coastal Orange County before starting it. The jobs here are the room off the back of a 1960s tract house, the unit at the rear fence, the bearing wall through a converted garage and the posts of a patio cover, and most start at the edge of a slab that was poured 12 inches into the sand before the code asked for more.
Footings are dug and poured under a CSLB C-8 license, with liability insurance on every job, to the California Residential Code and the engineer's sheet where the City asks for one. The permit comes from the City's Community Development Department, the trench is inspected open with the steel in it, and the concrete goes in the day the inspector signs. Every footing carries a written workmanship guarantee against defects in how it was built.