Chapter 17.39
ACCESSORY DWELLING UNITS

Sections:

17.39.010    Permitted uses.

17.39.020    Exemptions.

17.39.030    General requirements.

17.39.040    Inspection and registration.

17.39.010 Permitted uses.

Accessory dwelling units are permitted uses in the R-1 zoning district, subject to the requirements set forth in this chapter and the requirements of the individual zone. In the event that the applicable regulations conflict, this chapter shall control. (Ord. 805 § 1, 1999; Ord. 706 § 2, 1994)

17.39.020 Exemptions.

All legally nonconforming accessory dwelling units may be maintained after the effective date of this chapter without compliance with its requirements, subject to the provisions of Chapter 17.60 CHMC, Nonconforming Uses. Any other nonconforming accessory dwelling units existing at the time of adoption of this chapter must comply with the requirements set forth herein or be subject to an enforcement action under Chapter 17.80 CHMC, after February 1, 1995. (Ord. 805 § 1, 1999; Ord. 706 § 2, 1994)

17.39.030 General requirements.

A. Compliance with Applicable Codes. The accessory dwelling unit shall meet the requirements of all other applicable codes, including, but not limited to, the city’s building and fire code.

B. Certification by City of Bellevue Utilities Department. A certification must be provided by the Bellevue utilities department that the water supply and sewage disposal facilities for the accessory dwelling unit are adequate to serve the unit.

C. Attached to Main Dwelling Unit. The accessory dwelling unit must be attached to and made a part of the single-family dwelling unit, or be attached to and made a part of the detached garage for the single-family dwelling unit.

D. Limitation on Number of Accessory Dwelling Units. Only one accessory dwelling unit may be created per single-family dwelling unit in the R-1 zone.

E. Owner Occupation. The owner of the property must occupy either the single-family dwelling unit or the accessory dwelling unit as their legal residence. “Owner occupation” means a property owner, as shown in the records of title, makes his or her legal residence on the property, as evidenced by voter registration, vehicle registration or similar means, and actually resides on the property nine months out of a given year, and at no time receives rent for the owner-occupied unit.

F. Size Restrictions. The accessory dwelling unit shall contain not less than 300 square feet and not more than 900 square feet of gross floor area, excluding any related garage area, and more than 1,200 square feet of projected roof area. “Projected roof area,” as used in this section, means the area within the boundaries of the outermost portion of the vertical projection of the roof to the ground, including all gutters, breezeways, covered walkways, patios, porches and other extensions of the roof of the accessory living structure.

For accessory dwelling units that are attached to and made part of a detached garage, the size of the living quarters portion of the structure shall not exceed 750 square feet of gross floor area. In calculating the size of the “living quarters portion,” any stairway to the living quarters shall not be included except to the extent that the stairway exceeds 100 square feet. If the accessory unit that is converted from a previously existing building is completely located on a single floor, the public works director may allow increased size of up to 20 percent in order to efficiently use all floor area, so long as all other standards set forth in this chapter are met.

G. Square Footage. The square footage of the accessory dwelling unit, excluding any related garage area, shall not exceed 40 percent of the total square footage of the single-family dwelling and accessory dwelling unit combined, excluding any garage area. For accessory dwelling units that are attached to and made part of a detached garage, the square footage of the living quarters portion shall not exceed 750 square feet of gross floor area. In calculating the size of the “living quarters portion,” any stairway to the living quarters shall not be included except to the extent that the stairway exceeds 100 square feet.

H. Parking. There shall be at least one off-street parking space provided for the accessory dwelling unit, which space shall be in addition to any off-street spaces required for the single-family dwelling pursuant to Chapter 17.52 CHMC.

I. Conversion of Garage to ADU. An attached garage may be converted into an accessory dwelling unit only if the same number of off-street parking spaces on the property at the time of application for the accessory dwelling unit are maintained.

J. Entry Off Street. An entry door to the accessory dwelling unit shall not be located on the street side of the structure, regardless of whether the unit is attached to the single-family dwelling or the detached garage. An entry door to the accessory dwelling unit may be located on the side or rear of the structure, or on the street side of the structure where no other door exists. For accessory dwelling units located on corner lots, it is permissible to locate the entry door to the accessory dwelling unit on the street side of the structure; provided, that the entry door is not located on the same side of the single-family dwelling as is the entry door for the single-family dwelling. Existing single-family dwellings with two or more entry doors on the street side shall not be prohibited from using one of those doors to access the accessory dwelling unit.

K. Appearance. All of the structures on the property shall have the appearance of a single-family dwelling unit, or a single-family dwelling unit with a detached garage.

L. Limit on Occupants. The total number of occupants in both the primary residence and the accessory dwelling unit combined may not exceed the maximum number established under the definition of family in this title.

M. Separate Address. The accessory dwelling unit shall have a separate numbered address as established by the city.

N. Common Wall Requirement for Accessory Dwelling Units on a Detached Garage. Accessory dwelling units that are attached to and made part of a detached garage must have a common wall between the living quarters and the detached garage. A “common wall” means that the living quarters and the garage share either a wall of at least eight lineal feet or a ceiling and floor of at least 64 square feet (such that the floor of one is the ceiling of the other).

O. Setback Requirements for Accessory Dwelling Units. The reduced rear yard setback requirements for accessory buildings as stated in CHMC 17.16.060 shall not apply to accessory dwelling units. (Ord. 819 § 1, 2000; Ord. 805 § 1, 1999; Ord. 745 § 1, 1996; Ord. 706 § 2, 1994)

17.39.040 Inspection and registration.

A. Requirement of Registration. Any property owner seeking to establish an accessory dwelling unit shall apply to register the unit with the public works director.

B. Application for Registration. The property owner shall file a completed registration application form affirming that the property owner will occupy the single-family dwelling unit or the accessory dwelling unit, and agreeing to the standards within this chapter.

C. Inspection by Public Works Director – Approval. After receipt of a complete application form and prior to approval of any accessory dwelling unit, the public works director shall inspect the property to confirm that the standards of this chapter are satisfied. If these standards are met, the accessory dwelling unit shall be approved.

D. Recordation of Registration. After approval, the registration form or other form as required by the public works director shall be recorded against the property with the King County department of records and elections to indicate the presence of the accessory dwelling unit, the requirement of owner-occupancy, and other standards for maintaining the accessory dwelling unit as described in this chapter.

E. Cancellation of Registration. Cancellation of the accessory dwelling unit’s registration may be accomplished by the property owner’s filing a certificate with the public works director for recording at the King County department of records and elections, or may occur as a result of enforcement action.

F. Fees, Costs to Be Paid by Applicant. An application fee shall accompany the application described in subsection (A) of this section, which fee shall be determined by resolution of the city council. The property owner shall also be responsible to pay all recording and filing costs attributable to establishment, maintenance or cancellation of an accessory dwelling unit. The cancellation certificate will confirm that the residence has reverted to use as a single-family dwelling unit. (Ord. 805 § 1, 1999; Ord. 706 § 2, 1994)