Port Townsend, WA Accessory Structures: Tiny Homes (2026)
Tiny home rules in Port Townsend, WA, covering tiny houses on wheels (THOWs), park model RVs, and tiny home on foundation builds, determine where they are legal and how they get permitted.
Key Facts
- Max size
- 400 sq ft, excl. loft
- Zones
- R-I, R-II, R-III only
- Review type
- Type I (staff-level)
- Fire separation
- 5 feet minimum
- Design standard
- ANSI 119.5 certified
Summary
Port Townsend permits tiny houses on wheels as accessory dwelling units in R-I, R-II, and R-III zones, subject to Type I review, a 5-foot fire separation, and residential-style design standards.
As of July 1, 2023, tiny houses on wheels are permitted as accessory dwelling units in R-I, R-II, and R-III districts subject to the provisions of PTMC 17.16.020 and the requirements below:
A. Review. Tiny houses on wheels shall be subject to a Type I review.
B. Entry. To meet egress requirements, a front porch or landing approved by the city is required.
C. Separation. A tiny house on wheels shall be located at a fire separation distance of at least five feet from any other structures on the premises.
D. Appearance. To maintain the character of residential areas, a tiny house on wheels shall be designed to look like a conventional residential structure rather than a recreational vehicle. This shall be done by incorporating design features and materials typically used for houses, such as typical siding or roofing materials, pitched roofs, or residential windows.
E. Addressing. All tiny houses on wheels must obtain separate address approval from the city for the unit.
F. Utility Connection. A tiny house on wheels must have a permitted and permanent connection to all applicable municipal utilities. (Ord. 3361 § 4 (Exh. Q), 2025; Ord. 3306 § 1 (Exh. Z), 2023).
Official source re-checked September 8, 2026: no newer edition of the code had been published (publisher’s edition: current through Ordinance 3364, passed May 18, 2026).
Full Breakdown
PTMC 17.58 defines a tiny house on wheels as a towable unit up to 400 square feet (excluding loft) built to ANSI 119.5 standards. As of July 1, 2023, they're allowed as ADUs in R-I, R-II, and R-III districts under PTMC 17.58.040: the unit goes through Type I (staff-level) review, needs an approved entry porch, must sit at least five feet from other structures, must look like a house rather than an RV, gets its own address, and requires a permanent municipal utility hookup.
Violations & Fines
A THOW that skips Type I review, lacks ANSI 119.5/foundation certification, or fails the 5-foot separation or residential-appearance rules doesn't qualify as an ADU; the building official can require correction or reclassify it as an unpermitted recreational vehicle.
Frequently Asked Questions
Can I put a tiny house on wheels in my backyard in Port Townsend?
Does a tiny house on wheels count as an RV in Port Townsend?
Sources & Official References
Other rules in Port Townsend
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