Chapter 17.312
ACCESSORY DWELLING UNITS
Sections:
17.312.030 Use and general restrictions.
17.312.040 Development and design standards.
17.312.010 Purpose.
ORS 197.312 requires that at least one accessory dwelling unit be allowed per detached single-unit dwelling or duplex dwelling in every zone within an urban growth boundary that allows detached single-unit dwellings. Accessory dwelling units are an economical way to provide additional housing choices, particularly in communities with high land prices or a lack of investment in affordable housing. Accessory dwelling units provide an opportunity to increase housing supply in developed neighborhoods and can blend in well with single-unit detached dwellings. Accessory dwelling units may be used as long-term housing rentals (no less than 30 days per month and not a vacation rental) or as a property owner’s residence. [Ord. 540 § 6 (Exh. 1), 2021; Ord. 524 § 7 (Exh. A), 2020; Ord. 518 § 8 (Exh. 1), 2019; Ord. 503 § 1 (Exh. B), 2018].
17.312.020 Definition.
Repealed by Ord. 540. [Ord. 518 § 8 (Exh. 1), 2019; Ord. 503 § 1 (Exh. B), 2018].
17.312.030 Use and general restrictions.
An accessory dwelling unit, where allowed, is exempt from the land use process, pursuant to CBDC 17.130.030, except as per CBDC 17.312.040 where an accessory dwelling unit is subject to review and approval through a Type I procedure, pursuant to Chapter 17.130 CBDC.
All accessory dwelling units shall conform to the following restrictions:
(1) One accessory dwelling is allowed per legal lot of record containing a detached single-unit or duplex dwelling. The unit may be a detached building, in a portion of a detached accessory building (e.g., above a garage or workshop), a unit attached or interior to the primary dwelling (e.g., an addition or the conversion of an existing floor), certified factory-built home, or tiny home subject to the requirements of CBDC 17.312.040(1)(h);
(2) The accessory dwelling unit may not be used as vacation rental;
(3) Construction of an accessory dwelling unit must meet the minimum standards of the current state residential specialty code or the requirements of CBDC 17.312.040(1)(h);
(4) A separate address shall be assigned to the accessory dwelling unit and the address shall be clearly identified, as required by state building code; and
(5) A deed restriction must be recorded with the property advising future owners and lenders of the use restrictions. The deed restriction document will be created by the city and recorded at the county clerk’s office. [Ord. 540 § 6 (Exh. 1), 2021; Ord. 524 § 7 (Exh. A), 2020; Ord. 518 § 8 (Exh. 1), 2019; Ord. 503 § 1 (Exh. B), 2018].
17.312.040 Development and design standards.
(1) Development Standards. The development standards shall be applicable to all accessory dwelling units. An accessory dwelling unit is subject to the applicable development standards and general review pursuant to CBDC 17.130.030.
(a) A detached accessory dwelling unit shall not exceed 1,000 square feet of floor area, or 90 percent of the primary dwelling’s total floor area, whichever is smaller.
(b) An attached or interior accessory dwelling unit shall not exceed 1,000 square feet of floor area, or 90 percent of the primary dwelling’s total floor area, whichever is smaller. However, an accessory dwelling unit that results from the conversion of a level or floor (e.g., basement, attic, or second story) of the primary dwelling may occupy the entire level or floor, even if the floor area of the accessory dwelling unit would be more than 1,000 square feet.
(c) Accessory dwelling units shall meet all other development standards (e.g., height, setbacks, lot coverage, etc.) for buildings in the designated zoning district, except that conversion of an existing legal nonconforming structure to an accessory dwelling is allowed; provided, that the conversion does not increase the nonconformity.
(d) Accessory dwelling units are not subject to the density requirements of the zone.
(e) Accessory dwelling units shall conform to the overall maximum lot coverage and setback requirements of the underlying zone.
(f) Accessory dwelling units are not subject to the off-street parking requirements of CBDC 17.330.010.
(g) Structures detached from the primary home on a residential lot may be converted to an accessory dwelling unit if the structure meets the standards and requirements of the building code, this title’s setback requirements and does not eliminate an existing functional garage.
(h) A permanent tiny home may be attached to an approved foundation subject to the Oregon Residential Specialty Code (ORSC) and Oregon Fire Code or U.S. Department of Housing and Urban Development (HUD) Manufactured Home Construction and Safety Standards.
(i) A certified factory-built home used as an accessory dwelling unit and otherwise consistent with subsections (1)(a) through (h) of this section, as applicable, shall also be subject to the standards at CBDC 17.322.010.
(2) Design Standards for Historic Properties. The design standards shall be applicable only to those accessory dwelling units that are on lots that include a building listed on the National Register of Historic Places, lots that are within a historic zoning district, or a historic property that receives special assessment under Oregon law. An accessory dwelling unit, subject to both the development and design standards, is subject to review and approval through a Type I procedure, pursuant to CBDC 17.130.080.
(a) An accessory dwelling unit, located in a historic district, must comply with the historic district regulations.
(b) An accessory dwelling unit located on the same lot as a structure listed on the National Register of Historic Places or listed as a cultural resource will be held to a high development standard, in that the exterior must be compatible with the primary structure.
(c) The exterior finish and trim materials of a detached accessory dwelling unit shall be similar to the primary dwelling unit in terms of type, size, placement, and finish.
(d) The roof pitch of a detached accessory dwelling unit shall be similar to the roof pitch of the primary dwelling. [Ord. 540 § 6 (Exh. 1), 2021; Ord. 524 § 7 (Exh. A), 2020; Ord. 518 § 8 (Exh. 1), 2019; Ord. 503 § 1 (Exh. B), 2018].