Tumwater staff outline wide-ranging 2025 development‑code updates tied to state housing bills

Planning staff on Oct. 28 gave a detailed briefing on Ordinance O2025‑011, the city’s 2025 development‑code periodic update, describing numerous changes required by recent Washington state legislation and additional local code adjustments intended to implement the comprehensive‑plan update.

Erica Smith Erickson, housing and land‑use planner for the City of Tumwater, told the commission the update is intended to satisfy state deadlines and align the development regulations with the updated housing element. She said the ordinance must be adopted alongside the comprehensive‑plan amendments because state law requires certain development‑code changes to take effect concurrently.

Key items summarized by staff:

- Middle housing (state guidance/HB1110): The proposed code would allow two to four dwelling units per lot in most residential zones (the lower threshold is two units per lot; up to four units are permitted where at least one unit is affordable to households at or below 80% of area median income). Accessory dwelling units (ADUs) may count toward the dwelling‑unit allowance. Tumwater proposes applying the allowance to at least 75% of lots in primarily residential zones and excluding manufactured‑home parks and residential sensitive‑resource areas from the requirement.

- Accessory dwelling units (HB1337): Staff proposes allowing up to two ADUs per lot and raising the ADU maximum size from 800 to 1,000 square feet. Conversions of existing structures to ADUs would be permitted even when the structure does not meet current development‑standard setbacks, but expansions beyond the existing footprint would not be allowed. Staff said impact fees collected for ADUs would remain no greater than 50% of a single‑family residence’s fee, consistent with state provisions.

- Co‑living: The code would add a co‑living definition for privately rented sleeping units that share kitchen facilities. For density calculations, four sleeping units would count as one dwelling unit. State language caps parking requirements for co‑living at 0.25 off‑street spaces per sleeping unit (one space per four sleeping units), and staff noted the city cannot require more than that for co‑living projects.

- Parking and trees: The proposed update includes several parking changes—allowing tandem parking to count toward minimums, permitting grass‑block pavers as parking surfaces, reducing standard stall dimensions to 8 by 20 feet where appropriate, and allowing reductions for developments within a half mile of transit or with facilities for low‑income or senior households. Staff emphasized that tree retention provisions may take precedence over off‑street parking requirements in some cases.

- Religious‑sponsored housing and homeless encampments (HB1754): The draft adds a density bonus for affordable housing developed on property owned or controlled by a religious organization (affordability at ≤80% AMI and an affordability term of at least 50 years). The update also revises rules for religious‑sponsored temporary shelters, tiny‑home villages and safe‑parking programs and adds a definition of "homeless encampment." Commissioners discussed the use of permissive language such as "may" in the code text and the limits imposed by funding source requirements and state protections.

- Design review and code reorganization: Citywide design guidelines are being revised so middle housing is not subject to standards more restrictive than single‑family detached development. Staff described a reorganization of design‑review chapters so townhouses, cottage housing and ADUs are reviewed under updated chapters; the code will require concurrent land‑use and design review for residential projects.

Staff also reviewed the adoption schedule: a planning commission work session Nov. 10 (concurrent with the comprehensive‑plan public hearing), a development‑code hearing Nov. 25, a joint council work session Dec. 9, and council consideration targeted for late January. Staff warned that if Tumwater does not adopt required code changes by the end of the year a state model code could temporarily apply, and applicants might be vested to that model code if they submit complete applications during the interim.

Commissioners asked for clarification on design‑standard presentation format going forward, the mechanics of counting ADUs and middle‑housing lots (including filters such as critical‑areas restrictions, septic and well protection), and the interaction between tree retention and parking. Staff said additional code topics (urban forestry, critical‑areas amendments, unit‑lot subdivisions and short‑plat/condominium clarifications) are planned for 2026 code updates and invited further feedback.