ADU rules in Redmond

Table A in Redmond Development Code Sec. 8.135 lists 'Accessory Dwelling Unit/Accessory Suite' as 'O', permitted outright, in every residential zone (R-1, R-2, R-3, R-4, R-5), and the separate R-3A table in Sec. 8.137 does the same. Sec. 8.325 then sets the standards for a stand-alone (detached) unit: 300 to 900 sq ft of gross floor area, a 10 ft front setback, interior side of 5 or 10 ft in R-1 and R-2 and 5 ft elsewhere, a 10 ft street side, and rear setbacks running from 5 ft in R-5 up to 20 ft for a two-story unit in R-1 through R-3A. The ADU cannot sit in front of the forward-most facade of the primary dwelling, and if it is built above a garage it may not exceed the garage footprint. The city's Planning Division FAQ says the same thing in plain language: an ADU is an allowed use within all residential zones, subject to the setback and development standards in RDC Sec. 8.325.

The code's definition is explicit about form: an accessory dwelling unit is 'a secondary living unit, attached or detached, accessory to a single-family detached dwelling in a residential zone containing cooking facilities' (Sec. 8.020, under Dwelling). Sec. 8.325 covers both forms and requires that the unit function as a separate dwelling: separate exterior access (an interior entrance to the primary residence may be approved by the Community Development Director or designee), separately accessible utilities unless served by the primary residence, its own kitchen, its own bathroom, and no recreational vehicle used as the unit. Attached and internal conversions get no square-footage cap of their own in Sec. 8.325, since the 900 sq ft ceiling is written for stand-alone units; they are limited instead by the zone's dimensional standards. Watch Sec. 8.325(3), which requires the finished floor to be entirely above grade on all sides and so cuts against a below-grade basement conversion.

Sec. 8.325(1)(A) caps a stand-alone accessory dwelling unit at 900 square feet of gross floor area and sets a 300 square foot minimum. There is no percent-of-primary-dwelling formula and no lot-size sliding scale. Attached and internal ADUs are given no separate square-footage cap; Sec. 8.325(4) simply requires every ADU to sit within the dimensional requirements of its zone. Height comes from Table B in Sec. 8.140, which lists 'Single Family, Plexes, ADU' at 32 ft in R-1, R-2, R-3 and R-3A and 45 ft in R-4 and R-5, and the same figures repeat in the Sec. 8.325(1)(B) table. An ADU above a garage may not exceed the garage's footprint. A guest house, which the code treats as the same use without a kitchen, gets a larger 1,200 sq ft ceiling.

Nothing in Sec. 8.325 or anywhere else in Chapter 8 conditions an ADU on the owner living on the property; a full-text search of the development code turns up owner-occupancy language only for bed and breakfasts. State law forecloses the question in any event. ORS 197A.425(1)(b)(B), which carries forward former ORS 197.312(5) and (6) as recodified and amended by 2025 c.38 section 25, provides that reasonable local regulations relating to siting and design 'does not include owner-occupancy requirements of either the primary or accessory structure or requirements to construct additional off-street parking.' Redmond is far above the 2,500 population threshold in ORS 197A.425(1)(a); its own adopted findings in Ordinance No. 2025-22 apply the OAR 660-046-0220 rules that bind cities over 25,000. One narrow carve-out: ORS 197A.425(2) lets a city require owner occupancy in connection with vacation occupancies, and Redmond does use an owner-occupancy test in its short-term rental rules, but only for duplexes (City Code Sec. 7.136), not for ADU properties.

Redmond's off-street parking schedule in Sec. 8.500 has no line for an accessory dwelling unit. It prices a single-family detached dwelling at 2 spaces per unit, a duplex, triplex, quadplex or townhouse at 1 space per unit, and a guest house at 1 space, but it never lists an ADU, and ORS 197A.425(1)(b)(B) bars the city from requiring additional off-street parking as a condition of ADU approval. Two nearby rules should not be mistaken for an ADU parking minimum. First, the footnote to the Sec. 8.325(1)(B) setback table lets an owner get an administrative deviation from the ADU rear setback 'if acceptable off-street parking is provided for one vehicle' with notice to affected persons; that is a voluntary trade for a setback reduction the applicant asks for, not a condition of building. Second, renting the unit short term triggers City Code Sec. 7.138(2), which requires one off-street space per short-term rental on top of onsite parking requirements, a condition ORS 197A.425(2) expressly permits for vacation occupancies.

ADUs are 'O', permitted outright, in every residential zone under Table A (Sec. 8.135) and the R-3A table (Sec. 8.137). There is no conditional use permit and no public hearing. Review is administrative and layered: building permits apply, and because Sec. 8.3005 requires Site and Design Review for any new development or use containing a structure unless Sec. 8.3010 exempts it, a new detached ADU is caught (the exemption for 'single family detached dwellings and middle housing' does not name ADUs). Site and Design Review is decided by the Community Development Director as an administrative land use decision with prior notice under Sec. 8.3015 and Sec. 8.1310, appealable but never a discretionary hearing. Ordinance No. 2025-22, passed February 10, 2026 and not yet reflected in the Municode text, lightens this further by adding Minor Site and Design Review for any structure under 3,500 sq ft, which covers every ADU, and directing that it be processed as a Development Action under Sec. 8.1205, a director decision without public notice or hearing. An attached ADU built as an addition of less than 25 percent of the building's square footage and no more than 1,000 sq ft is exempt from Site and Design Review outright under Sec. 8.3010(5).

Nothing in the Redmond Development Code restricts renting an ADU long term, and Chapter 8 contains no minimum-lease term, no primary-residence test and no bar on selling or platting the ADU separately. Short-term rentals, meaning stays of less than 30 consecutive days, are governed by City Code Sec. 7.132 through 7.140. They are permitted in residential zones with a short-term rental permit, a city business license and transient lodging tax registration. The line that matters for ADU owners is in Sec. 7.136: on a residential property containing both a residential dwelling and an accessory residential dwelling, only one of the two units may be rented as a short-term rental, not both. Sec. 7.138 adds one off-street space per short-term rental, a cap of three occupants over age three per bedroom, a local responsible party living near Redmond, weekly solid waste pickup, no on-premise or off-premise signage, and a non-transferable permit the Community Development Director can revoke.