Benicia has adopted Municipal Code 17.70.060 Accessory Dwelling Units
D. Design and Development Standards.
1. Lot Size. Accessory dwelling units shall only be permitted on residential lots of 6,000 square feet or greater.
2. Lot Coverage. The basic requirements of Chapter 17.24 BMC shall apply.
3. Unit Size. An accessory dwelling unit, whether within, attached to, or detached from the existing structure, shall not exceed 800 square feet, or the size of the primary dwelling unit, whichever is less. The existing unit may be considered the accessory unit, and a new dwelling unit built, if all applicable standards and requirements of this title are met.
4. Building Location.
a. Accessory dwelling units shall not be permitted in a required yard or court except if a rear yard is adjacent to an alley and a four-foot setback for a vehicle entrance to a covered parking structure is maintained.
b. A six-foot distance from any existing dwelling shall be maintained.
5. Building Height. The maximum height of a detached accessory dwelling unit shall be 12 feet, except that pitched roofs may have a height of 15 feet. The maximum height of any wall shall not exceed 12 feet at the eaves. No second story, other than an unfinished storage area, may be developed for any accessory building.
6. Parking. A minimum of three off-street parking spaces shall be required for a lot containing an accessory dwelling. One parking space, which is not required to be covered, shall serve the accessory unit. The additional parking space for the accessory dwelling unit shall not be placed within the required front yard setback unless, at the discretion of the community development director, or designee, there is no other reasonable place for the additional parking space to be located and appropriate landscaping and/or berming is provided to mitigate any adverse aesthetic impacts.
a. Accessory dwelling units shall be designed to be compatible and in harmony with existing development in the immediate neighborhood. Building materials, architectural features, colors, and exterior finishes should be substantially similar as those on the existing dwelling unit.
b. The orientation of accessory dwelling units on the lot shall be designed so that the privacy of adjacent neighbors is reasonably preserved. This includes measures such as limiting windows that have openings facing adjacent properties, height considerations, and/or window glass treatments.
c. An accessory dwelling unit shall have a backlit illuminated address sign.