PNW Fire Hardening

Washington defensible space and WUI code basics

This page describes Washington rules and official guidance as of November 2026. It is not legal, insurance, or building-code advice. Local ordinances and the state’s mapping project are still moving. Confirm requirements with your city or county building department and your fire district.

If you live in Washington and want to know whether a wildland-urban interface (WUI) code requires you to clear vegetation around your house, the short answer in November 2026 is: the state building code does not currently impose a statewide defensible-space requirement. The Washington Department of Natural Resources (DNR) and Firewise USA® publish voluntary guidance. Cities and counties may adopt additional WUI provisions, including defensible space, on their own. A limited set of statewide construction provisions is written into statute, but those provisions take effect only when DNR finishes new statewide maps — and, as of November 2026, those maps were still in draft.

Where the state WUI code stands now

Washington previously adopted a state version of the 2021 International Wildland-Urban Interface Code, with amendments, in chapter 51-55 of the Washington Administrative Code. In 2024, Engrossed Senate Bill 6120 changed that path. It limited what the statewide WUI code can require, directed DNR to complete a new statewide wildfire hazard map and a base-level wildfire risk map for each county, and left broader International WUI Code provisions — including defensible space — to local adoption.

In March 2026, the State Building Code Council rescinded the state amendments that had implemented the 2021 WUI Code and reserved the sections of chapter 51-55 WAC. The permanent rule, WSR 26-07-075, took effect April 17, 2026. The Council’s accompanying emergency filing explained that the 2021 WUI Code cannot be adopted and maintained without the new DNR mapping, and that the Council will adopt portions of the WUI Code as directed by ESB 6120. You can see the reserved chapter at chapter 51-55 WAC.

So, as of November 2026, there is no active statewide WAC chapter filling in a complete WUI code. What remains in force as a statute is RCW 19.27.560, which sets out what the state building code will include upon completion of the DNR maps, and what local governments may do in the meantime.

What RCW 19.27.560 will require — and what it will not

Once the statewide wildfire hazard map and the county base-level risk maps are complete, the statute says the state building code shall consist of chapter 1 of the International Wildland-Urban Interface Code plus a limited list of technical provisions. Those provisions address:

That statutory list is about how buildings and driveways are built. It does not include defensible-space or vegetation-management rules. RCW 19.27.560(2) says all counties, cities, and towns may adopt the International Wildland-Urban Interface Code in whole or in any portion. If a local government wants to enforce defensible-space provisions from that code, it needs to adopt those provisions itself.

The same statute says that six months after the statewide maps are complete, any map a local government uses for this purpose must use the same or substantially similar criteria as DNR’s maps. It also says that counties, cities, and towns issuing commercial and residential building permits for parcels identified as high hazard or very high hazard on the applicable map shall apply the code described in the statute (the limited statewide provisions, or a locally adopted International WUI Code).

Map status as of November 2026

DNR’s official Wildfire Hazard and Risk Mapping page, as reviewed in November 2026, presents draft maps and describes public listening sessions held around the state in 2026. The page describes the project’s intended products: a statewide hazard map with low, moderate, high, and very high categories; county-level base-level risk maps; public access to the finished maps; and a method for updates. It did not, on that review, describe the maps as final.

The Washington State Association of Fire Marshals, writing about the same project, reported that DNR expected final publication by December 1, 2026, after a second comment period ending November 1, and that required use of the DNR map — or a local map with substantially similar criteria — would follow six months later, around June 2027 if that schedule holds. Treat those dates as a reported expectation, not as a completed event, and check DNR’s page for the current status.

Until the maps are final, the limited statewide construction provisions in RCW 19.27.560 have not been triggered by map completion. Local governments may already have their own adopted WUI rules or maps. The only reliable way to know what applies at your address is to ask your building department and fire marshal.

Voluntary defensible-space guidance from DNR and Firewise

Separate from the building code, DNR encourages homeowners to prepare the area around the house. Its page Defensible Space — Prepare Your Home points to fire-resistant plant guidance, the Firewise USA® program, outdoor-burning rules, and evacuation planning (Ready, Set, Go!). DNR works with local fire districts, conservation districts, counties, and WSU Extension on Firewise USA®, which is administered by the National Fire Protection Association (NFPA).

DNR’s public handout 12 Steps to Defend Your Home from Wildfire (posted in DNR’s files as of 2025) says homes built in forests should have a minimum defensible space of 100 feet, and that homes on steep slopes may need more. Among its steps: rake and remove leaves, dead limbs, and vegetation against the house; thin a 15-foot space between tree crowns and remove limbs within 15 feet of the ground; remove branches that extend over the roof; prune vegetation within 15 feet of a chimney; clear ten feet around propane tanks; and stack firewood at least 100 feet away and uphill, with combustibles cleared within 20 feet of the pile.

Those distances are DNR’s published recommendations in that handout. They are not the same, number for number, as Oregon State Fire Marshal guidance or as the IBHS Wildfire Prepared Home standard, which treats the first five feet as a noncombustible zone and discusses firewood in the 5–30-foot area. When advice conflicts, read the source that applies to the program or code you are following, and ask your local fire district which standard they use for assessments or cost-share work. Our home-hardening checklist walks through the IBHS and NFPA items in more detail.

What to do now

If you are building or remodeling, ask your building department whether any local WUI code applies, whether a local hazard map is in use, and whether R327-style or International WUI construction rules (roofs, walls, decks, driveways) have been adopted locally. If you are improving an existing yard, DNR’s guidance and a Firewise or fire-district assessment are practical starting points even when no vegetation code applies.

DNR also offers technical and financial assistance for qualifying forestland owners; see our grants and cost-share guide. To hire help, browse Washington contractors in this directory or search listings. This site defaults to contractors whose Washington L&I registration we could verify as Active. Read how to choose and vet a contractor before you sign.

For Oregon’s different legal structure — a repealed statewide map and a model code that cities may adopt — see Oregon defensible-space requirements.

Related guides

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