Chelan County's Wildland-Urban Interface Building Code

Why Chelan County wrote its own fire code

Chelan County's decision to adopt a dedicated Wildland-Urban Interface (WUI) building code wasn't precautionary -- it followed direct, repeated experience. The 2014 Chiwaukum Fire burned nearly 15,000 acres and threatened hundreds of residences. The 2015 Chelan Complex Fires, on the south end of Lake Chelan, burned more than 95,000 acres and destroyed over 50 homes, serious enough that the county declared a state of emergency. In 2024, the Pioneer Fire burned through the Okanogan-Wenatchee National Forest on the lake's north side. Much of the county's newer development -- including second-home and resort construction around Lake Chelan -- sits directly in dry ponderosa pine and shrub-steppe terrain that historically burned on a frequent natural cycle, making this a structural risk built into the landscape rather than a rare event.

In response, the county's fire marshal was directed to draft a WUI-specific building code, reviewing similar ordinances already adopted by the cities of Wenatchee and Leavenworth within the county. The draft went to a public hearing on May 10, 2022, and the resulting code is now codified as Chapter 15.06 of the Chelan County Code -- a real, adopted piece of county law, not a proposal still in limbo.

What the code actually requires

The code applies within the county's mapped wildland-urban interface zones, and covers both new construction and substantial renovations -- specifically, any project that would replace 50% or more of a structural component within a 12-month period. Within scope, the draft/adopted framework requires ignition-resistant materials across the entire building exterior (roofing, siding, and vent screening designed to resist ember intrusion), along with a defensible-space plan addressing vegetation management around the structure, generally following National Fire Protection Association Standard 1144 concepts -- a cleared perimeter immediately around the structure, with graduated vegetation-thinning requirements extending outward. A comprehensive fire-protection plan submitted with a building application is expected to address water supply for firefighting, site access for emergency vehicles, and long-term vegetation-management maintenance, not just the initial as-built condition.

Because this page relies on the 2022 draft code and secondary reporting rather than a full pull of the current, final Chapter 15.06 text, treat the specific defensible-space distances and material standards described here as indicative of the code's structure and intent rather than an exact, current specification. Before finalizing house plans or a construction budget for raw land in Chelan County, get the current Chapter 15.06 text and any associated WUI zone map directly from the county.

What this means for buying and building on raw land here

1. Ask Chelan County Community Development directly whether a specific parcel falls inside a mapped Wildland-Urban Interface zone before assuming standard residential building-code costs and materials will apply.
2. If it does, budget for ignition-resistant exterior materials and vent screening as a real added construction cost, not an optional upgrade -- these are code requirements within WUI zones, not a design preference.
3. Ask what the parcel's defensible-space plan will need to include and whether existing vegetation on the lot would need to be cleared or thinned before a building permit is issued, since this affects both upfront cost and how much of a wooded lot's character survives development.
4. If insurance is part of your planning, note that a documented WUI code and defensible-space plan can also be directly relevant to wildfire-insurance underwriting in this area -- ask a carrier familiar with Chelan County specifically rather than assuming standard homeowner's coverage applies at standard rates.