A.
Purpose. Accessory dwelling units (ADUs) are intended to increase the supply of affordable and independent housing for a variety of house-holds, increase home and personal security, provide supplemental earnings for people with limited incomes, and increase residential densities. This should occur by utilizing the existing infrastructure and community resources throughout the City while protecting the existing character of low density residential neighborhoods.
B.
General Requirements. The creation of an ADU shall be subject to the following general requirements:
1.
Number. Up to two ADUs shall be allowed per lot of record as an accessory use in conjunction with any detached single-family structure, provided, only one detached ADU shall be allowed on a lot that does not meet the minimum lot size for the zone in which the property is located. One ADU shall be allowed on a lot of record as an accessory use in conjunction with a two-unit middle housing building type, provided, the lot conforms to the minimum lot size for the zone in which the property is located.
2.
Type of Unit. An ADU may be attached to the principal unit, a separate detached accessory structure (e.g., cottage), or part of a detached accessory structure (e.g., carriage unit above garage).
3.
Size. An ADU shall not exceed 1,000 square feet; provided, if the ADU is to be established within an existing multistory structure and located entirely on a single floor, the Director may allow increased size in order to efficiently use all area of this single floor.
4.
Location. An attached ADU shall be physically connected to the principal unit by a shared wall or attached covered structure. Attached ADUs shall meet the same setbacks, height requirements, and other dimensional standards as the principal unit.
A detached ADU not to exceed 1,000 square feet may be placed in a side and/or rear yard in accordance with UPMC § 19.45.040H and shall comply with the following building standards:
a.
The total area of a detached ADU and other detached accessory structures placed in a side or rear yard shall not exceed the size limitations set forth in UPMC § 19.45.040H.1.a.
(1)
The total ground floor footprint of a structure with an ADU located above (e.g., carriage unit) shall not exceed 600 square feet in gross floor area;
(2)
For ground floor ADUs that exceed 600 square feet in gross floor area, no additional accessory structure floor area (e.g., garages, carports, and sheds) shall be permitted in the side or rear yard setback;
b.
Maintain five-foot minimum side and rear yard setbacks;
c.
Have no portion of the structure, such as eaves, closer than three feet from any property line;
d.
Be no greater than 24 feet in height at top of ridge and 10 feet at the top wall plate where the roof structure connects to the wall, if located within a required side or rear yard;
e.
Be no closer than five feet to the primary structure;
f.
No more than one detached ADU may be placed within the reduced setbacks. Any second detached ADU must comply with the setbacks applicable to the principal unit; and
5.
Parking. No off-street parking shall be required for an ADU when the property is within one-half mile walking distance of a major transit stop as defined in RCW 36.70A.696. Property not subject to this exemption shall provide off-street parking for accessory dwelling units as follows:
a.
One off-street parking space shall be required per ADU on lots 6,000 square feet or smaller.
b.
Two off-street parking spaces shall be required per ADU on lots greater than 6,000 square feet.
c.
Any additional off-street parking provided in conjunction with an ADU shall, to the extent possible, be located to the side or rear of the principal unit to minimize visual impacts on the streetscape. Such parking must be provided in the rear of the lot when alley access is available. Off-street parking shall be designed to reduce impacts on adjoining properties through the installation of vegetative screening and/or fencing.
6.
In order to encourage the development of housing units for people with disabilities, the Director may allow reasonable deviation from the requirements of this section when necessary to install features that facilitate accessibility. These facilities shall conform to Washington State regulations for barrier-free facilities.
C.
Procedures. Any owner seeking to establish an ADU shall apply for approval in accordance with the following procedures:
1.
Application. The owner shall apply for a building permit for an ADU. A complete application form must demonstrate that all size thresholds and parking standards are met.
2.
Notice of Title. Prior to issuance of building permits, the owner shall record a notice on the property title acknowledging the existence of the ADU with the Pierce County Auditor. Such notice shall be in a form as specified by the Department.
3.
Reports. The Department shall report annually to the City Council on ADU applications, the number of units established and their distribution throughout the City, the average size of the units, and the number and types of complaints and enforcement-related actions.
(Ord. 307 § 2, 2001; Ord. 394 § 1, 2003; Ord. 443 § 1 (Exh. A), 2005; Ord. 559 § 10 (Exh. A), 2009; Ord. 607 § 1 (Exh. A), 2012; Ord. 688 § 1 (Exh. A), 2017; Ord. 741 § 1 (Exh. O), 2020; Ord. 775 § 1 (Exh. A), 2023; Ord. 788 § 7 (Exh. G), 2025; Ord. 797, 12/1/2025)


