Chapter 17.77
ACCESSORY DWELLING UNITS (ADU)
Sections:
Prior legislation: Ords. 1884, 1942 and 1981.
17.77.005 Purpose.
The purpose of this chapter is to allow for establishment of an accessory dwelling unit (ADU) in conjunction with a single-family detached dwelling within zones that allow single-family detached dwellings in accordance with ORS 197.312. ADUs are intended to provide more economical housing choices while encouraging additional density with minimal cost and disruption to surrounding neighborhoods and allowing more efficient use of large, older homes. (Ord. 2064 §3(part), 2020).
17.77.010 Applicability.
Accessory dwelling units (ADUs) shall be a permitted use in the R-L, R-1, and R-2 residential districts, and LMR, MMR, and HMR mixed-use districts within the transit oriented development (TOD) district, as accessory to single-family dwellings subject to the provisions of this chapter. (Ord. 2064 §3(part), 2020).
17.77.020 One unit.
A maximum of one ADU shall be allowed per legally established single-family dwelling. The unit may be a detached building, in a portion of a detached accessory building (e.g., above a detached garage or workshop), or attached to or interior to the primary dwelling (e.g., addition or conversion of floor area within the existing building). (Ord. 2064 §3(part), 2020).
17.77.030 Approval criteria.
A. Floor Area. The maximum floor area allowed for an ADU shall be eight hundred square feet or fifty percent of the gross floor area of the primary dwelling, whichever is less, except that conversion of a new or existing level or floor (e.g., attic, or second story) of a detached accessory building (e.g., garage, workshop) to an ADU is permitted even if the floor area of the ADU would be more than eight hundred square feet.
B. Development Standards. ADUs shall meet all development standards required for residential structures per the base zone requirements (e.g., building height, setbacks, lot coverage, building design, etc.) except for the following:
1. Density. ADUs are exempt from the maximum density standard in the base zone in which the ADU is located; provided, that all other base zone standards are met.
2. Conversion of Nonconforming Structures. Conversion of an existing legally nonconforming structure to an ADU is allowed; provided, that the conversion does not increase the nonconformity and the structure complies with the Oregon Residential Specialty Code.
3. Parking. In accordance with ORS 197.312, off-street parking shall not be required to approve an ADU.
4. Rear Yard Setback. The rear yard setback for ADUs shall be five feet.
5. Building Height. Except for units constructed above a detached garage (e.g., carriage units), detached ADUs shall be limited to single-story construction and shall not exceed twenty-five feet in building height per the accessory building height standards set forth in Section 17.60.030(C)(1).
C. Other Standards.
1. Unit Separation. For attached and interior ADUs, the primary dwelling and ADU shall be distinct with wall separation, separate building entrances and visible addresses.
2. Utilities. Separate utility connections may be provided at the applicant’s discretion. Separate connections are not required.
3. Transfer Prohibited. No subdivision of land, air rights or condominium is allowed so as to enable the sale or transfer of the accessory dwelling unit independently of the main dwelling unit or other portions of the property. (Ord. 2064 §3(part), 2020).