Auburn City Zoning Code
18.32 Accessory
Dwelling Unit Development Standards
18.32.010 Accessory dwelling unit development standards.
A. Accessory dwelling units (ADUs) are permitted outright in all residential zones that permit single-unit detached or middle housing, and may be developed with new or existing development. The development standards of the underlying zone and the following siting and performance standards shall apply to all accessory dwelling units as defined by ACC 18.04.018.
B. Two ADUs may be permitted per residential unit on individually owned lots that meet the minimum lot size of the zone in which the property is located.
C. The two ADUs may be attached, detached, or any combination thereof.
D. An ADU shall not be larger than 1,000 square feet, nor less than 300 square feet, nor have more than two bedrooms. Garage space shall not be included in this calculation.
E. Exterior Appearance/Modifications.
1. Any alterations shall not change the appearance from that of a single-unit detached dwelling, as determined by the planning director.
2. Any exterior stairs shall be placed in the rear or side setback and no closer than 10 feet to an adjoining property line.
3. Where garage space is converted to living space, the garage door shall be replaced with materials that match the exterior of the house.
F. Parking Requirements.
1. Off-street parking is not required for ADUs that are located within one-half mile walking distance of a major transit stop.
2. For ADUs located more than one-half mile walking distance from a major transit stop, one on-site parking space is required per ADU.
G. An ADU may be sold as a condominium unit or as a separate piece of property through the unit lot subdivision process. If the ADU is converted into a condominium unit or subdivided, a separate water and sewer connection is required.
H. ADUs must be connected to municipal sewer or served by septic system.
I. An ADU is allowed in rear setbacks (on the rear lot line) if the lot line abuts a public alley, unless the city routinely plows snow within the alley.
J. Conversion of legally established structures that do not conform to current zoning and/or land use standards to an ADU shall not be required to come into conformance.
K. Any property owner seeking to establish an ADU shall apply for approval in accordance with the following procedures:
1. The owner shall apply for an ADU permit with the city. A complete application shall include a properly completed application form, floor and structural plans, and fees.
2. Before final of an ADU, the owner must provide a copy of a statement recorded with the county in which the subject property is located. The statement must read:
An application for a permit for an accessory dwelling unit has been submitted to the city of Auburn by the owner of this property. Future owners are advised that the owner of the property must comply with all requirements of the Auburn Zoning Code, as amended, if the accessory dwelling unit is to be occupied or rented.
L. If an ADU is to be removed, appropriate permits and inspections must first be received from the city. If a homeowner wants to remove the statement as required by subsection (K)(2) of this section from the property’s title, then the city shall issue an appropriate release upon evidence that the ADU has been removed. The release shall be recorded by the homeowner with the county records and elections office and a copy of the recorded release shall be provided to the city. (Ord. 6959 § 1 (Exh. A), 2024.)