As wildfires increasingly encroach on neighborhoods, states are turning to Wildland-Urban Interface (WUI) building codes to ensure homes are better equipped to survive. This new generation of wildfire-focused building codes aims to reduce the destruction of homes, expedite rebuilding after disasters, and help homeowners retain insurance coverage. Research also shows that constructing new homes to these standards is highly cost-effective and needed to avoid far-reaching economic losses.
Tracking state wildfire building codes in the Western United States
Western states have taken widely varying approaches to wildfire codes. In some cases, measures for building standards, defensible space, emergency vehicle access, and water infrastructure are enforced across all fire-prone areas of the state. In other cases, local governments are given significant leeway to establish their own codes.
To monitor how building standards are shifting, Headwaters Economics created an online dashboard detailing the provisions and status of wildfire building codes across Western states. The dashboard provides an overview of each state’s approach, direct links to codes and risk maps, and the history behind each state’s regulatory efforts. States designated as having a “code in place” require all communities statewide to adopt and enforce a minimum WUI code for new residential construction.
As of April 2026, California and Colorado are the only states with mandatory wildfire codes in effect statewide, and Utah recently passed a law requiring local jurisdictions adopt a code by 2029. Oregon and Washington have made efforts to adopt statewide codes, but they have yet to go into effect. Nevada has some statewide regulations and allows for significant delegation of authority to local jurisdictions that wish to adopt more stringent requirements. Montana allows local jurisdictions to adopt a limited, pre-approved statewide wildfire building code, but local implementation is voluntary, enforcement is limited, and local jurisdictions cannot adopt additional protections. Arizona, New Mexico, Idaho and Wyoming do not have statewide wildfire building codes but allow local governments to adopt their own regulations.
The wide variation in WUI code adoption across states reflects both the newness of this tool and the complexity of implementing it. Yet policymakers are increasingly recognizing that stronger building standards are necessary. Unlike other natural hazards, wildfire risk is shaped significantly by the built environment itself because homes and structures act as sources of ignition, spreading fire from property to property. This means that individual action alone is insufficient: a homeowner who replaces their roof and clears defensible space remains highly exposed if their neighbors have not done the same. Because risk is shared across properties, neighborhood-wide adoption of protective measures is what actually reduces it. That kind of collective action is difficult to achieve without policy intervention. Wildfire building codes are one of the most direct tools available to policymakers working toward that goal.
Understanding WUI codes
A Wildland Urban Interface (WUI) code is a set of building and land use standards designed to reduce the risk of wildfire in areas of risk. These codes typically address construction materials, defensible space, landscaping, site design, road standards, and water access. They establish baseline protections that can make the difference between a home that survives a wildfire and one that doesn’t. Research shows that homes built to these standards are much more likely to survive a wildfire.
The International Code Council (ICC) developed a model International WUI Code that communities can adopt as a foundation, though these represent a minimum standard. Communities can tailor selected ICC provisions to reflect their specific hazard environments, local vegetation, topography, and climate conditions. For added resilience, WUI codes can also be layered with voluntary certification programs, such as the Wildfire Prepared Home program from the Insurance Institute for Business & Home Safety.
Adopting a WUI code can signal to insurance companies that a community is taking wildfire risk reduction seriously, potentially influencing coverage availability and premiums in high-risk areas, but adoption can be challenging. Communities must weigh the consistency of statewide codes against the ease of implementing localized approaches. Additionally, wildfire risk mapping can be controversial, often requiring sustained public engagement and clear guidance on how maps are used to evaluate risk, rather than influence insurance rates or other properly assessments.
Acknowledgements
Marcus Pearson of Marcus Pearson of Pearson Law Group contributed knowledge and expertise to this research.
