Home Remodeling in
Tumwater, WA

Tumwater has a lot of addresses that read as Tumwater but sit outside the city boundary, in the Tumwater urban growth area. Those properties are not governed by Tumwater municipal code. They fall under Thurston County Code Title 22, the Tumwater Urban Growth Area zoning.

It is the single most common thing that trips people up locally. Different permitting office, different rules, different fees, and plans drawn to the wrong standard get sent back.

If you are not certain which side of the line you are on, that is the first call to make, before anything gets designed.

Tumwater runs a Permit Services counter on the main floor of City Hall at 555 Israel Road SW, first come first served, Monday to Friday. There is no appointment system to work around.

Some projects can be permitted fully over the counter, so you leave with the permit in hand. Many need plans left for review, and how long that takes depends on the queue and the complexity of the work.

Renovations, remodels, repairs, additions, demolition, relocation, and plumbing, electrical and mechanical work all require a permit here. Community Development takes questions on (360) 754-4180.

Tumwater municipal code at TMC 18.42.010 states there shall be no more than one accessory dwelling unit per lot alongside a single-family structure. The code is current through Ordinance O2026-019, passed 19 May 2026, and the council has been working through a package of updates that includes clarifying ADU language.

State law asks for more than the published figure. HB 1337 requires jurisdictions planning under the Growth Management Act to allow two ADUs per lot inside urban growth areas, prohibits capping an ADU below 1,000 square feet, and prohibits owner-occupancy requirements. Those requirements have applied since 30 June 2026, and where local code still conflicts, state law overrides it.

So the same advice applies here as in Lacey: confirm how the city is applying the standard with Community Development in the week you apply rather than designing to a number you read online, including this one.

The upside is that Tumwater now leads the three-city pre-approved ADU plan partnership with Olympia and Lacey, and The Artisans Group, the firm that designed the four plans, is based on Capitol Boulevard here in Tumwater. The plans run from a 480 square foot studio to an 800 square foot two bedroom and have already been reviewed for code compliance.