Wildland Urban Interface Codes

A Wildland Urban Interface Code (WUI code) provides a minimum set of regulations designed to reduce the wildfire risk to lives and property. Its purpose is to prevent wildfire spreading from vegetation to a structure and to prevent structure fires from spreading to wildland fuels.

WUI codes can be adopted as stand-alone codes that work in conjunction with the local fire and building codes, or as a chapter or appendix to one of these codes. The standards and requirements in these codes can vary greatly and are usually based on the goals and objectives the community has embraced to support lowering its wildfire risk. These standards usually include the following:

  • Requirements for structures including building materials, construction, density, and location;
  • Vegetation management;
  • Emergency vehicle access standards including road widths and turnarounds, address signage, access points; and
  • Additional fire protection standards including water supply, sprinkler systems, and restrictions on hazardous land uses.

WUI codes can be drafted by the community, or communities can adopt one of the model codes such as the International Wildland-Urban Interface Code (IWUIC) or the National Fire Protection Association’s Standard for Wildland Fire Protection (NFPA 1140). Regardless, communities must also decide what will be regulated by those standards.  Examples include:

  • Undeveloped land within a designated hazard area
  • Existing structures
  • New construction
  • Additions, decks, etc.
  • Certain land uses

WUI codes offer an organized and convenient location to house a community’s wildfire mitigation regulations. This makes it not only easier for community members and developers to locate the standards they may be required to abide by, but also more user-friendly for staff to reference in their decision-making process.

Community Examples

Flagstaff, Arizona

Flagstaff adopted the IWUIC in 2008 which was modified to include local amendments that were concerns of the community. The code covers all lands in the designated WUI zones, which includes the majority of the lands within the city limits.