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A. Purpose. It is the purpose of this legislation to implement the policy provisions of the housing element of the city’s comprehensive plan by eliminating barriers to accessory dwelling units in single-family residential neighborhoods and provide for affordable housing. Also, to provide homeowners with a means of obtaining rental income, companionship, security and services through tenants in either the accessory dwelling unit or principal unit of the single-family dwelling.

B. Requirements for Accessory Dwelling Units. One accessory dwelling unit is permitted as subordinate to an existing single-family dwelling; provided, the following requirements are met:

1. Owner Occupancy. Either the principal dwelling unit or the accessory dwelling unit must be occupied by an owner of the property or an immediate family member of the property owner. Owner occupancy is defined as a property owner, as reflected in title records, who makes his or her legal residence at the site, as evidenced by voter registration, vehicle registration, or similar means, and actually resides at the site more than six months out of any given year.

2. Number of Occupants. The total number of occupants in both the principal dwelling unit and accessory dwelling unit combined shall not exceed the maximum number established for a family as defined in MICC 19.16.010 plus any live-in household employees of such family.

3. Subdivision. Accessory dwelling units shall not be subdivided or otherwise segregated in ownership from the principal dwelling unit.

4. Size and Scale. The square footage of the accessory dwelling unit shall be a minimum of 220 square feet and a maximum of 900 square feet, excluding any garage area; provided, the square footage of the accessory dwelling unit shall not exceed 80 percent of the total square footage of the primary dwelling unit, excluding the garage area, as it exists or as it may be modified.

5. Location. The accessory dwelling unit may be added to or included within the principal unit, or located in a detached structure.

6. Entrances. The single-family dwelling containing the accessory dwelling unit shall have only one entrance on each front or street side of the residence except where more than one entrance existed on or before January 17, 1995.

7. Additions. Additions to an existing structure or newly constructed detached structures created for the purpose of developing an accessory dwelling unit shall be designed consistent with the existing roof pitch, siding, and windows of the principal dwelling unit.

8. Detached Structures. Accessory dwelling units shall be permitted in a detached structure.

9. Parking. All single-family dwellings with an accessory dwelling unit shall meet the parking requirements pursuant to MICC 19.02.020(G) applicable to the dwelling if it did not have such an accessory dwelling unit.

C. Exceptions – Ceiling Height. All existing accessory dwelling units that are located within a single-family dwelling, which was legally constructed but does not now comply with current ceiling height requirements of the construction codes set forth in MICC Title 17, shall be allowed to continue in their present form.

D. Notice on Title. Approval of the accessory dwelling unit shall be subject to the applicant recording a document with the King County department of records and elections which runs with the land and identifies the address of the property, states that the owner(s) resides in either the principal dwelling unit or the accessory dwelling unit, includes a statement that the owner(s) will notify any prospective purchasers of the limitations of this section, and provides for the removal of the accessory dwelling unit if any of the requirements of this chapter are violated.

E. Elimination/Expiration. Elimination of an accessory dwelling unit may be accomplished by the owner recording a certificate with the King County department of records and elections and development services stating that the accessory dwelling unit no longer exists on the property. (Ord. 18C-08 § 1 (Att A.); Ord. 08C-01 § 1; Ord. 04C-12 § 10; Ord. 99C-13 § 1).