The City of El Cerrito has adopted Ordinance No. 2017-04 relating to ADUs.
Accessory Dwelling Units shall conform to setback, height, lot coverage, and other development standards applicable to the primary dwelling unit in the zoning district where the Accessory Dwelling Unit is proposed, subject to the following additional standards.
1. Location on Lot.
a. Detached Units—Interior Lots. A detached Accessory Dwelling Unit shall be located behind the primary dwelling in relation to the front lot line. For the purpose of this regulation, “behind” shall mean that at least one of the following criteria is met:
- All portions of the Accessory Dwelling Unit are located behind all portions of the primary unit.
- The Accessory Dwelling Unit is located partially behind the primary dwelling unit, and the front façade of the Accessory Dwelling Unit is at least 20 feet farther from the front lot line than is the front façade of the primary unit.
- The Accessory Dwelling Unit is located entirely in the rear half of the lot.
b. Detached Units—Corner Lots. On corner lots, the standard of Subsection (a) above shall be met on the front of the property. In addition, a detached Accessory Dwelling Unit shall not be located closer than the primary dwelling unit to the street-facing side lot line.
c. Attached Units.
- The exterior entry to the Accessory Dwelling Unit shall be located at least 10 feet behind the exterior entry to the primary unit, or shall be located on the side or rear of the dwelling.
- If an attached ADU is created through an addition to an existing single-family dwelling at the second or higher story of the dwelling, such ADU shall be located in the rear half of the structure.
2. Conversion of Garages. An Accessory Dwelling Unit that is created through the conversion of an existing attached or detached garage and is located entirely within the footprint of such garage may maintain the existing garage setback, irrespective of whether the setback conforms to the required.
3. Maximum Floor Area. The habitable floor area of an attached or detached Accessory Dwelling Unit shall not exceed 50 percent of the habitable floor area of the primary dwelling unit, up to a maximum of 1,200 square feet. These shall be the resulting habitable floor areas of each unit after construction, addition, or conversion to create the Accessory Dwelling Unit.
4. Minimum Floor Area. An Accessory Dwelling Unit must have a floor area of at least 150 square feet.
5. Height—Detached Units. The maximum height of a detached Accessory Dwelling Unit is 15 feet.