23.42.022

A. Accessory dwelling units are allowed as a housing use in all zones where housing uses are allowed. In the Shoreline District, accessory dwelling units shall comply with Chapter 23.60A . B. Accessory dwelling units may not be accessory to residential uses other than housing uses. C. No lot may have more than two accessory dwelling units. D. Accessory dwelling units may be attached, detached, or stacked. E. Unless otherwise provided in the standards of the underlying zone, accessory dwelling units shall be subject to the same standards as principal dwelling units. F. Accessory dwelling units must be located on the same lot as the principal dwelling unit. G. Maximum size 1. Gross floor area limit a. The gross floor area of an accessory dwelling unit with up to two bedrooms may not exceed 1,000 square feet, except as provided in subsection 23.42.022.G.1.c. b. The gross floor area of an accessory dwelling unit with three or more bedrooms may not exceed 1,200 square feet, except as provided in subsection 23.42.022.G.1.c. c. The gross floor area of an accessory dwelling unit regardless of number of bedrooms may not exceed 1,500 square feet if: 1) The lot is located in a LR zone; 2) The lot is located in a frequent transit service area; and 3) The lot has not been purchased for more than $1,000 in the past 20 years. 2. The following are not included in the gross floor area limit: a. Up to 250 square feet of gross floor area in an attached garage; b. All stories, or portions of stories, that are underground; and c. Up to 35 square feet of gross floor area dedicated to long-term bicycle parking. H. Conversions of existing structures 1. For purposes of this subsection 23.42.022.H, the term "conversion" means keeping an existing structure intact, adding to or altering an existing structure, or removing and rebuilding an existing structure, provided that any expansion or relocation of the structure complies with the development standards for accessory dwelling units in this Section 23.42.022 and the provisions of the applicable zone, unless otherwise allowed by this subsection 23.42.022.H. 2. For the purposes of this subsection 23.42.022.H, the term "existing accessory structure" means an accessory structure existing prior to July 23, 2023 or an accessory structure existing prior to July 23, 2023 that was subsequently replaced to the same configuration. 3. Existing accessory structures. An existing accessory structure may be converted into a detached accessory dwelling unit if it meets the following: a. To facilitate the conversion of and additions to an existing accessory structure, the Director may allow waivers and modifications as a Type I decision to the provisions for accessory dwelling units in this Section 23.42.022 and the development standards of the applicable zone. b. Conversion of an existing accessory structure to a detached accessory dwelling unit is permitted notwithstanding applicable lot coverage or yard or setback provisions in this Section 23.42.022 or the applicable zone. The converted accessory structure shall comply with the minimum standards set forth in Sections 22.206.020 through 22.206.140 . 4. Existing principal structures. The gross floor area of an attached accessory dwelling unit may exceed 1,000 square feet if the portion of the structure in which the attached accessory dwelling unit is located existed as of July 23, 2023. I. No off-street motor vehicle parking is required for an accessory dwelling unit. J. When calculating density, the number of dwelling units shall include both accessory dwelling units and principal dwelling units. K. Title 23 shall not be interpreted or applied to prohibit the sale or other conveyance of a condominium unit on the grounds that the condominium unit was originally built as an accessory dwelling unit. L. Unless provided otherwise in this Section 23.42.022 , the provisions of the applicable zone and overlay district apply. In the event of conflict with provisions elsewhere in Title 23 other than Chapter 23.60A , this Section 23.42.022 shall prevail. (Ord. 127376 , § 21, 2025; Ord. 127211 , § 5, 2025.)