A. Permitted locations. An accessory dwelling unit or junior accessory dwelling unit shall be allowed if the existing lot and dwelling meet the following requirements:
1. Accessory dwelling unit or junior accessory dwelling unit is allowed in the zone in which it is proposed.
2. The lot on which the accessory dwelling unit or junior accessory dwelling unit is proposed to be established shall contain at least one existing or proposed permanent main dwelling unit.
B. Number of units per lot.
1. Properties with a proposed or existing single-family dwelling.
a. One accessory dwelling unit that is within the proposed space of a single-family dwelling or existing space of a single-family dwelling or accessory structure;
b. One detached, or attached newly constructed accessory dwelling unit; and
c. One junior accessory dwelling unit.
2. Properties with a proposed or existing multi-family dwelling.
a. One interior accessory dwelling unit or up to 25% of the existing units, whichever is higher; and
(1) Interior accessory dwelling unit means an accessory dwelling unit that is created by converting portions of existing multi-family dwelling structures that are not used as livable space, including, but not limited to, storage rooms, boiler rooms, passageways, attics, basements or garages.
(2) When calculating the required number of allowed accessory dwelling units, any fractions of units shall be rounded to the next larger whole number.
b. Up to two detached accessory dwelling units.
C. The following development standards contained in Table 20.52.040.A (Accessory Dwelling Unit Development Standards) apply based on the type of unit and the applicable development standards. All accessory dwelling units are required to comply with all applicable standards:
Accessory Dwelling Unit, Junior | Accessory Dwelling Unit | ||
Attached | Detached | ||
Accessory Dwelling Unit, Junior | Accessory Dwelling Unit | ||
Attached | Detached | ||
Minimum Unit Size | 150 square feet | 150 square feet | |
Maximum Unit Size | 500 square feet Note: Up to 150 square feet may be added to an existing primary dwelling unit to accommodate ingress or egress, but the unit size for the junior accessory dwelling unit shall not exceed 500 square feet. | No more than 50% of the existing primary dwelling unit square footage, or 1,200 square feet, whichever is less. | 1,200 square feet |
Notes: If an Accessory Dwelling Unit is created by converting an existing space, there is no maximum unit size requirement. Such conversion may include an expansion of not more than 150 square feet beyond the same physical dimensions as the existing structure if the expansion is for the sole purpose of accommodating ingress and egress to the converted area. | |||
Maximum Site Coverage | The standards of the underlying zone shall apply | 800 sq. ft.: No maximum >800 sq. ft.: The standards of the underlying zone shall apply | |
Maximum Rear Yard Coverage | The standards of the underlying zone shall apply | 800 sq. ft.: No maximum >800 sq. ft.: The standards of the underlying zone shall apply | |
Minimum Outdoor Living Space | The standards of the underlying zone shall apply | 800 sq. ft.: No maximum >800 sq. ft.: The standards of the underlying zone shall apply | |
Minimum Setbacks | The standards of the underlying zone shall apply | Front - The standards of the underlying zone shall apply Side - 4 feet Rear - 4 feet Notes: A detached accessory dwelling unit shall be located no closer than the front-most building wall of the primary dwelling unit No additional building setback shall be required for an accessory dwelling unit that is created by conversion of an existing space, such as primary dwelling unit, garage, accessory structure, if the accessory dwelling unit is created in the same location and to the same dimensions as an existing structure. Front yard setback may be reduced if applying the standards of the underlying zone prevents creation of an 800 square-foot unit. | |
Maximum Structural Height | The standards of the underlying zone shall apply | 25 feet or the standards of the underlying zone, whichever is lower Note: If an accessory dwelling unit is attached to the second floor of the primary dwelling unit, the maximum height shall be the height of the existing primary dwelling unit. | 16 feet maximum Note: If the accessory dwelling unit is located on a lot with an existing or proposed multi-family dwelling that is multi-story, or located within mile walking distance of a major transit stop or a high-quality transit corridor, the maximum height shall be 18 feet. |
Minimum Distance Between Buildings | Not Applicable | Not Applicable | Minimum 10 feet between the main dwelling unit and the detached accessory dwelling unit Note: No additional building separation is required for an existing garage or an existing accessory building that is converted to an accessory dwelling unit |
Access | Must have independent entrance from the exterior into the Junior Accessory Dwelling Unit If the unit shares sanitation facility with the primary dwelling, the unit must also include an interior access to the primary dwelling | Must have independent entrance from the exterior into the accessory dwelling unit | |
Minimum Kitchen Requirements | Efficiency kitchen | ||
Sanitation Facility | May share sanitation facility with main dwelling unit or have separate sanitation facility | Must have separate sanitation facility | |
Minimum Parking Requirements | As specified in § 20.08.040.D. of this title. | ||
D. Unit size calculation. When calculating the unit size, non-livable space attached to any accessory dwelling units, including, but not limited to, attached garages, porches, patios, overhangs, and balconies shall not be included.
E. Design standards. The following design standards shall apply to all types of accessory dwelling units:
1. Addressing. Address numerals of all dwelling units on the lot shall be displayed clearly visible from the street or displayed in a building directory.
2. Windows and doors.
a. Windows and doors of the new unit shall not have a direct line of sight to a neighboring residential property unless the windows and doors are existing or they are properly screened by fencing, landscaping, or privacy glass.
b. If an accessory dwelling unit or a junior accessory dwelling unit is located within a single-family zoning district, new doors shall not open on the same elevation as the main entrance door to the primary dwelling, except for detached structures and conversion of an existing door opening to an entry door.
3. Staircases. If an accessory dwelling unit or a junior accessory dwelling units is located within a single-family zoning district, new stairways shall be completely enclosed as part of the interior of the structure, except for conversion/modification of an existing exterior stairway.
4. Architecture.
a. The roof slope must match that of the dominant roof slope of the primary dwelling. The dominant roof slope is the slope shared by the largest portion of the roof.
b. The new unit shall match the building architecture, exterior materials, finishes, and color of the primary dwelling unit.
F. Attached accessory structures. All accessory structures attached to an accessory dwelling unit or a junior accessory dwelling unit, including but not limited to, patio covers, porches, garages, and balconies, shall comply with requirements of the underlying zone.
G. Emergency access. Adequate access by emergency services to the primary dwelling unit, accessory dwelling unit, and junior accessory dwelling unit shall be provided.
H. Fire sprinklers. The installation of fire sprinklers shall not be required in an accessory dwelling unit or junior accessory dwelling unit if sprinklers are not required for the primary residence. The construction of an accessory dwelling unit shall not trigger a requirement for fire sprinklers to be installed in the existing multifamily dwelling.
I. Nonconforming conditions. The correction of a physical improvement on a lot that does not conform with the city's current zoning standards is not required in order to establish an accessory dwelling unit or a junior accessory dwelling unit on such lot.
J. Code compliance. All accessory dwelling units shall comply with all applicable Fire and Building Codes.
K. Any proposed junior accessory dwelling unit that does not conform to requirements of § 20.52.040.E. or accessory dwelling unit that does not conform to the maximum unit size specified in Table 20.52.040.A and/or requirements of § 20.52.040.E. may be considered by the city through a Certificate of Compatibility process pursuant to § 20.408.050 of this Title.
(Ord. 1242, passed 8-15-23; Am. Ord. 1247, passed 3-19-24)