Fire Hazard Severity Zone Map

Fire Hazard Severity Zone Maps classify the level of wildland fire hazards in a given area. The current Fire Hazard Severity Zone Map for Lafayette went into effect on July 10, 2025.

In addition to helping you understand the likelihood of wildfire in a given location, the zones have different levels of California’s defensible space standards and WUI building codes, so landowners should be aware of the various requirements within Zones. For information regarding home hardening and defensible space clearance, visit www.readyforwildfire.org.

• "Wildland-Urban Interface" (WUI) Building Codes: California’s WUI building codes apply to the design and construction of new buildings located in High and Very High FHSZs in Local Responsibility Areas. These requirements are intended to reduce the risk of embers fanned by wind-blown wildfires from igniting buildings and address roofing, siding, decking, windows and vents.

• Defensible Space Requirements: Per Government Code 51182, there currently is a 100-foot defensible space clearance requirement for properties within Very High Fire Hazard Severity Zones. Note: Recently, the Governor also announced plans to advance implementation of regulations known as "Zone 0,” which will require an ember-resistant zone within 5 feet of structures. We will update this page as more information is available.

• Natural hazard disclosure requirement: Since 2021, sellers of residential properties (including condominiums) in a high or very high fire hazard severity zone need to provide documentation that their property complies with defensible space laws, or buyers must agree to obtain such documentation of compliance in the future. Download Contra Costa Fire’s instructions for requesting an AB38 Real Property Transfer Inspection.

In February 2024, the State Fire Marshal released their recommended updated Fire Hazard Severity Zones for Local Responsibility Areas (LRA) in the Bay Area. Contra Costa Fire was the lead agency to adopt the new maps (not the City) and by State law, could not decrease or remove areas from the State’s recommended map. The County Board of Supervisors, in its capacity as the Board of Directors of the Contra Costa County Fire Protection District, adopted the recommended map on July 10, 2025.

CAL FIRE developed the map using a science-based and field-tested model that assigns a hazard score based on the factors that influence fire likelihood and fire behavior. The fire hazard severity model for wildland fire has two key elements: probability of an area burning and expected fire behavior under extreme fuel and weather conditions. Many factors are considered, such as fire history, existing and potential fuel (natural vegetation), predicted flame length, blowing embers, terrain, and typical fire weather for an area. Read more about CAL FIRE's methodology.

Lafayette’s previous map was adopted in 2013. At that time, areas were either rated Very High or were not rated at all.  Recent changes in State law now require the State to develop Fire Hazard Severity Zone Maps that identify moderate and high zones in addition to very high zones.

Note: The Fire Hazard Severity Zone map reflects “hazard,” not “risk”. The map is like a flood zone map, where lands are described in terms of the probability level of a particular area being inundated by floodwaters; “Hazard” is based on the physical conditions that create a likelihood and expected fire behavior over a 30 to 50-year period without considering mitigation measures such as home hardening, recent wildfire, or fuel reduction efforts.

Additional Resources and Links

• CAL FIRE Fire Hazard Severity Zones webpage

• California Department of Insurance Wildfire Recovery and Readiness 

• Are You Ready?

• Lamorinda Residents Guide to Wildfire Preparedness & Evacuation Booklet (Updated 2022)

• Wildfire Preparedness and Firewise

• Con Fire website | Con Fire Defensible Space Brochure 

• CAL FIRE Preparedness Resources: Prepare  |  Defensible Space  |    Home Hardening