Accessory Dwelling Unit (ADU) City Guidelines


R-1 | R-2 | R-M

Lot Size:

Attached ADU - 5,500 sq.ft. minimum

Detached ADU - 7,500 sq.ft. minimum and must meet setback standards

Maximum ADU Floor Area:

Lots smaller than 6,500 sq.ft.:

    Attached ADU - must not exceed 50% of living area of existing single-family dwelling, not including the garage.

Lots larger than 6,500 sq.ft.:

    Attached ADU - 1,000 sq.ft. max

Detached ADU - 1,000 sq.ft. max, but must follow maximum size formula (Unit size may be increased by 1 sq.ft. for each 10 sq.ft. of lot size in excess of 6,500 sq.ft.)

ADUs and main dwelling must not exceed allowable floor area or lot coverages of underlying zoning districts.

No. of Bedrooms:  

No min/max, however, ADU must not be occupied by more than 3 people as permanent living quarters.

Storage / Closet:

No min/max

Kitchen / Bath:  

Require a separate bathroom (partial or full bathroom) and kitchen facilities (permanent range, counters, refrigerator, sink).  


One uncovered off-street parking space is required for the ADU in addition to the required parking spaces for the main dwelling.

Parking Exceptions:

No additional parking required if ADU:

  1. Is located within one-half mile of public transit.

  2. Is part of existing primary residence or existing accessory structure.

  3. Is located within an architecturally and/or historically significant district.

  4. When on-street parking permits are required but not offered to the occupants of ADU.

  5. Is located within one block of a car share vehicle.


Detached ADUs: Rear Setback - 6’ | Side Property Lines - 3’ | Streetside Property Line - 12’ | From Main Dwelling - 6’

Garage Conversion: No setbacks

ADU Constructed Over Garage: Side AND Rear lot lines setback - no more than 5’

Attached ADU - Setbacks must be sufficient for fire safety.


Must meet all development standards of underlying zone.



Rear Yard Coverage:

750 sq.ft. of usable open space must be provided in the rear yard.

Materials / Design:

The ADU must be compatible with exterior appearance and character of the main dwelling, and with the existing neighborhood in terms of form, bulk, height, material, and landscaping.


ADU must be served by the same driveway as the existing main dwelling. Attached ADU and main dwelling must be served by a common entrance or a separate entrance to the ADU must be located on the side or at the rear of the main dwelling.

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