Solano County, CA Accessory Structures: Garage Conversions (2026)

Garage conversions in unincorporated Solano County are handled primarily through the ADU/JADU provisions of Chapter 28, tracking California ADU law (Gov. Code 66310 et seq.). When an ADU is created by converting an existing structure, the code provides that no additional setback beyond what already exists is required - a key state-law protection that lets homeowners reuse a garage footprint. A junior ADU must be contained entirely within an existing or proposed single-family dwelling and have a separate exterior entrance, making garage conversions a common JADU pathway. The code also states that when an existing garage, carport, or covered parking structure is demolished or converted in conjunction with creating an ADU, replacement parking standards are limited. Importantly, the County's residential standards require a two-car enclosed garage to accompany each primary dwelling, so converting your only garage to living space may require providing replacement covered parking for the main home. All conversions need building permits and must meet Building Code requirements that apply to a detached dwelling unit, including separate egress, light, and ventilation. Confirm details with the Planning Division (707-784-6765) before starting.