Concord Municipal Code see 18.200.180 Accessory Dwelling Units

Extract:

Accessory Dwelling Unit Regulations.

1. Allowed Use. Accessory dwelling units are allowed in all single-family residential (RR, RS) districts, low density residential districts (RL), and other districts where a legal detached single-family dwelling exists.

2. Limitation. No more than one accessory dwelling unit or junior accessory dwelling unit shall be allowed per legal principal dwelling.

3. Size. On lots less than 12,000 square feet in net area, only small accessory dwelling units are allowed. On lots at or over 12,000 square feet in net area, both small and large accessory dwelling units are allowed.

4. Zoning Development Standards. The principal dwelling and the accessory dwelling unit shall meet all provisions of the zoning district in which they are located, including setbacks, height, and parking requirements and other applicable provisions of the development code, except as allowed by this section.

5. Setbacks.

a. Setback Requirements by Type of Accessory Dwelling Unit.

Type of accessory dwelling unit

Conversion of existing living area within a principal dwelling

Existing accessory building conversion

New addition to an existing principal dwelling

New detached building

Required setback

No additional setback, but distance must be sufficient for fire safety.

Five-foot side and rear setback.

b. Setbacks for Second-Story Accessory Dwelling Units. A minimum setback of five feet from the side and rear lot linesshall be required for a second-story accessory dwelling unit proposed above a garage or principal dwelling as a second-story. For accessory dwelling units proposed above a garage or principal dwelling, the accessory dwelling unit shall not project beyond the front building line of the principal dwelling for which the unit is constructed upon.

c. Front and Corner-Side Setbacks. Accessory dwelling units shall comply with the minimum required front and corner-side setbacks required for the principal dwelling, except as modified by this section.

6. Lot Coverage. The accessory dwelling units shall meet the lot coverage requirement of the district in which they are located, except as allowed by this section. An efficiency unit as defined above is allowed as an attached or detached dwelling regardless of the existing lot coverage.

7. Size.

a. Small Accessory Dwelling Units. The total floor area of a small accessory dwelling unit shall be no less than 150 square feet or more than 640 square feet, exclusive of the carport or garage. The small accessory dwelling unit shall have no more than one bedroom.

b. Large Accessory Dwelling Units. The total floor area of the large accessory dwelling unit must be over 640 square feet and no larger than 1,200 square feet, exclusive of the carport or garage. The large accessory dwelling unit shall have no more than two bedrooms.

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Concord has an ADU Interim Submittal Requirements Checklist