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

H. Development Standards. 1. Setbacks. The following setbacks are applicable for all accessory dwelling units: a. An existing structure may be converted into an accessory dwelling unit or junior accessory dwelling unit without a setback. If the existing structure requires an expansion of 150 square feet or less to accommodate an accessory dwelling unit or junior accessory dwelling unit, the setback shall be no less than 4 feet from side and rear property lines, or as otherwise required to provide for fire safety. b. If the parcel cannot accommodate the setback imposed by the applicable zone, the setback maybe no less than 4 feet from side and rear property lines for new accessory dwelling units not developed within or converted from an existing structure. 3. Parking. The following parking standards are applicable for all accessory dwelling units: a. A maximum of 1 space shall be provided per bedroom or per accessory dwelling unit, whichever is less. b. Tandem parking (i.e., when two or more vehicles are parked on a driveway or in any other location on a lot, lined up behind one another) within an existing driveway, and within setbacks is allowed unless specific site conditions and topography make tandem parking infeasible. c. No replacement parking is required for the conversion of an existing parking area such as a garage, carport or covered parking structure into an accessory dwelling unit. d. No parking shall be required for accessory dwelling units if any one of the following applies: 1. The accessory dwelling unit is within one-half mile walking distance of public transit, including transit stops. 2. The accessory dwelling unit is located on a site of historic significance. 3. The accessory dwelling unit is part of the proposed or existing primary residence or an accessory structure.