Whittier, CA Accessory Structures: Garage Conversions (2026)

Converting an existing garage in the incorporated City of Whittier is regulated by the city's ADU/JADU provisions in Whittier Municipal Code Section 18.10.020(I). A garage (attached or detached) may be converted to an accessory dwelling unit, and a junior accessory dwelling unit may be created within an existing or proposed single-family residence including an attached garage. The ordinance follows state law on parking: when a garage, carport or covered/uncovered parking is demolished or converted in conjunction with creating an ADU, the off-street parking spaces do not have to be replaced. However, if a single-family garage is demolished or converted, the driveway must either continue to function so a car can lawfully park on it, or the applicant must (at their own cost) remove the driveway, curb cut and apron and install replacement curb, gutter and parkway. Converted ADUs require no minimum setback when created within the existing footprint, and a demolition permit for a detached garage being replaced by an ADU is reviewed and issued together with the ADU permit. Junior ADUs (Sec. 18.10.020(I)(7)) are capped at 500 square feet, must include an efficiency kitchen, require the owner to occupy either the primary dwelling or the JADU as a primary residence, may not be sold separately, may not be rented for under 31 days, and require a recorded deed restriction before permit finalization. Historic-district or landmark properties trigger Chapter 18.84 review. These are city ordinances; unincorporated Whittier areas follow LA County.