Existing law, the California Building Standards Law, establishes the California Building Standards Commission within the Government Operations Agency. Existing law requires the commission to approve and adopt building standards and to codify those standards in the California Building Standards Code. Existing law, the California Factory-Built Housing Law, generally regulates the design, manufacture, and installation of factory-built housing, as defined and specified. That law specifically and entirely reserves to local jurisdictions certain local requirements, including local use zone requirements, snow load requirements, and wind pressure requirements. That law provides that any person who violates any of those provisions and other specified law is guilty of a misdemeanor, as specified. This bill also would prohibit a city, county, city and county, or district from imposing or enforcing local building standards applicable to a factory-built housing structure, as defined, that exceed or differ from the applicable mandatory standards contained in the California Building Standards Code. The bill would authorize a city or county to make changes or modifications in the requirements contained in the provisions published in the California Building Standards Code that are reasonably necessary to maintain minimum health and safety because of local climatic, geological, or topographical conditions, subject to the city or county making a specified finding. The bill would create a rebuttable presumption in favor of a determination that facilitates the use of factory-built housing and allows a project to qualify as a factory-built housing structure. This bill would define certain key terms for purposes of the California Factory-Built Housing Law. In this regard, the bill would define "building assembly" to mean assembled construction materials, components, subsystems, subassemblies or other systems designed for use in, or as part of, factory-built housing, and "factory-built housing structure" as a residential building where at least 23 of the new or converted square footage is designated for residential use and in which at least 30% of the residential use portion of the building is built using factory-built housing. The bill would recast the definition of "factory-built housing" to mean, among other things, a residential building, dwelling unit, building component, building assembly, or building system that is manufactured in a specified manner. The bill would make other conforming changes to definitions in the California Factory-Built Housing Law, the Sales and Use Tax Law, and the Vehicle Code. By adding to the duties of local officials, and expanding the scope of a crime, this bill would impose a state-mandated local program. The bill would include findings that certain changes proposed by this bill address a matter of statewide concern rather than a municipal affair and, therefore, apply to all cities, including charter cities. The California Constitution requires the state to reimburse local agencies and school districts for certain costs mandated by the state. Statutory provisions establish procedures for making that reimbursement. This bill would provide that no reimbursement is required by this act for specified reasons.