California Code, Health and Safety Code - HSC § 19993

(a) Local use zone requirements, local snow load requirements, local wind pressure requirements, local fire zones, building setback, side and rear yard requirements, site development and property line requirements, as well as the review and regulation of architectural and aesthetic requirements are hereby specifically and entirely reserved to local jurisdictions notwithstanding any requirement of this part.

(b) Local requirements imposed on factory-built housing pursuant to the authority granted by this section shall not vary substantially from the requirements imposed on other residential buildings of similar size.