ADU rules in Sherwood

A detached backyard ADU is a permitted (P) use in all five of Sherwood's residential zones: VLDR, LDR, MDRL, MDRH and HDR. Zoning and Community Development Code 16.52.020.A lets a homeowner create one ADU per single-family detached dwelling by 'Constructing a detached ADU on a site with an existing house' or by building a new house with a detached ADU. The siting rules are real but ministerial: a detached ADU may only sit in the rear yard or above a detached garage, it must meet the underlying zone's setbacks (a 20-foot rear yard in every residential zone), it may be no taller than the primary residence, and its entrance may not be visible from the street the house is addressed from. Detached ADUs are exempt from the Ch. 16.50 accessory-structure standards, so the 15-foot accessory-structure height cap does not apply.

Attached and internal ADUs are allowed on the same terms as detached ones. Section 16.52.020.A lists four permitted creation methods and three of them are attached or internal: converting existing living area, attic, basement or garage; adding floor area; or constructing a new house with an internal ADU. The same 800 square foot cap and the same design and appearance standards apply, though the requirement that the entrance not be visible from the addressing street and the rear-yard-only location rule are written for detached units only. No conditional use permit or hearing is involved.

Section 16.52.020.D caps the ADU at 800 square feet of gross habitable floor area. It is a flat number: there is no percentage-of-primary-dwelling formula, no per-zone split, and no separate footprint rule. Height is handled in 16.52.020.F, which limits a detached ADU to no higher than the primary residence (the underlying residential zones themselves permit 30 to 40 feet or 2 to 3 stories depending on zone, so the house is normally the binding constraint). Sherwood's development standards table in 16.12.030 sets no minimum lot area for an ADU, so lot size is not a size gate.

No owner-occupancy requirement, at application or ongoing. Sherwood did have one: Ord. 2019-003 wrote 16.52.020.B as 'The property owner ... must occupy either the principal unit or the ADU as their permanent residence for at least six months out of the year, and at no time receive rent for the owner-occupied unit.' Ord. No. 2021-010, § 2, adopted 12-7-2021, rewrote the section and deleted that subsection along with a three-person occupancy cap; the codified chapter now runs A through F with no occupancy clause, and a full-text sweep of Title 16 finds no owner-occupancy language anywhere. State law backs this up: ORS 197A.425(1)(b)(B) says reasonable local siting and design regulations 'does not include owner-occupancy requirements of either the primary or accessory structure.' Sherwood's code and the statute agree, so there is no conflict to work around.

Section 16.52.020.C is explicit: 'Parking: No off-street parking is required for an Accessory Dwelling Unit,' with a footnote crediting '2017 Senate Bill 1051 and 2019 House Bill 2001.' The off-street parking table at 16.94.020 agrees, listing Accessory Dwelling Unit with a minimum parking standard of None (a single detached house, by contrast, needs 1 space). Nothing turns on transit proximity here, though the same table separately zeroes out parking within a half mile of a frequent transit corridor and inside the Sherwood Town Center climate-friendly area. Sherwood's rule already matches ORS 197A.425(1)(b)(B), which bars requiring additional off-street parking as an ADU condition, so no state preemption analysis is needed.

Administrative, no hearing. The use table at 16.12.020 marks Accessory Dwelling Unit as P (Permitted) in VLDR, LDR, MDRL, MDRH and HDR, and 16.72.010.A.2.n places accessory dwelling units in the Type I review process, which is the city's staff-level administrative track. Before the building permit issues, the ADU also clears a Residential Design Checklist Review: 16.89.020.A lists Accessory Dwelling Unit first among the housing types that need one, and 16.72.010.A.1 describes it as a ministerial decision the Community Development Director makes 'without public notice and without a public hearing' against clear and objective standards. Discretion only enters if the applicant chooses it, by pairing the checklist with a Type I Adjustment or Type II Class B Variance, or opting into the Type IV Residential Design Review before the Planning Commission.

Renting the ADU is the point of the chapter: 16.52.010 says the purpose of an ADU is 'to provide homeowners with a means of obtaining rental income, companionship and security.' There is no minimum lease term, no primary-residence test and no cap on the number of occupants (the three-person cap that Ord. 2019-003 carried was deleted in 2021). Sherwood has no short-term-rental licensing chapter and no vacation-rental use category anywhere in Title 16, so an ADU rented by the night is not separately permitted or prohibited by the zoning code. What does apply is Chapter 3.30: a 3 percent local transient lodging tax on occupancy of under 30 consecutive days in any 'dwelling unit, or portions of any of these dwelling units, used for temporary human occupancy,' and 3.30.080 requires the person collecting it to register with the city (within 15 days of starting). On sale, note that an ADU is defined as accessory to a single dwelling on a single lot or parcel, and the code contains no mechanism to convey it separately.