Chapter 17.63
ACCESSORY DWELLING UNITS (ADUs)
Sections:
17.63.030 Development standards.
17.63.050 Conditions for legalizing preexisting accessory dwelling units.
17.63.010 Purpose.
This chapter provides for accessory dwelling units (“ADUs”) on lots developed or to be developed with single-family dwellings to contribute to the community’s housing stock consistent with the comprehensive plan objectives and zoning regulations and to enhance the community’s housing opportunities. (Ord. 1571 § 1, 2021).
17.63.020 Applicability.
An ADU that meets the requirements of this chapter may be allowed in the R-2, R-3, and R-4 residential districts. Accessory dwelling units are not allowed in the R-1 residential district. (Ord. 1571 § 1, 2021).
17.63.030 Development standards.
(a) No more than one ADU per development site is allowed. The ADU must be accessory to a single-family residence, and only one ADU is allowed per single-family residence.
(b) Maximum lot coverage for all buildings on the lot, including the ADU, the single-family house, and any garages, sheds, shops, or other accessory buildings, shall be the same as allowed in the zone.
(c) To promote the visibility and accessibility of the ADU for emergency services providers, the ADU must be connected to a public street with a concrete or asphalt walkway with a minimum four-foot width. The walkway must be kept clear of obstructions.
(d) The ADU and the primary residence associated with the ADU must conform to Chapter 17.61, Off-Street Parking. In addition, two off-street parking spaces shall be provided for the first bedroom of the ADU and one additional off-street parking space shall be provided for each additional bedroom of the ADU.
(e) Height of a detached ADU shall be no more than twenty feet.
(f) A detached ADU shall have a connection to the public water main in the right-of-way and meters for water, electricity and natural gas utilities that are independent of the water main connection and utility meters for the primary residence.
(g) The ADU shall have a numerical street address that is distinct from that of its primary residence, which distinction shall be made with whole numbers and not with letters, fractions or other symbols. If the ADU’s street address cannot be read by a person standing at the curbside of the street on which it is located, the ADU’s street address shall be posted at the street with signage that meets the requirements of emergency services providers.
(h) Unless specifically provided for otherwise by this chapter, an ADU shall comply with all requirements of applicable zoning codes, building codes, electrical codes, fire codes, and energy codes, including but not limited to the International Residential Code, International Property Maintenance Code, International Fire Code, and the Washington State Energy Code.
(i) The minimum setback of an ADU from an alley shall be five feet.
(j) The ADU shall not be sold separately from the primary residence, unless all requirements of a subdivision are met prior to the sale closing.
(k) An ADU shall comply with all bedroom and living room requirements of the International Property Maintenance Code Section 404.4.
(l) An ADU shall have no more than two bedrooms. Maximum size of the ADU shall be nine hundred square feet. (Ord. 1571 § 1, 2021).
17.63.040 Owner occupancy.
For new ADUs established in the R-2, R-3, or R-4 zone after October 25, 2021, the property owner must occupy either the main house or the accessory dwelling unit from the time of application for the ADU building permit until at least one year after issuance of the certificate of occupancy of the ADU. (Ord. 1571 § 1, 2021).
17.63.050 Conditions for legalizing preexisting accessory dwelling units.
A nonconforming residence in existence prior to October 25, 2021, may be brought into compliance pursuant to Chapter 17.79. A nonconforming residence in existence prior to October 25, 2021, whether (a) before building permits were required, or (b) when building permits were required but were not obtained for the residence, may be designated as a legal nonconforming residence by complying with current life safety standards. (Ord. 1571 § 1, 2021).