LA Fire Hazard Severity Zones: 2025 Maps.

Before you plan a new roof in Los Angeles County, find out one thing: is the house in a Fire Hazard Severity Zone? The answer changes which roof materials are allowed and which extra parts, like vents and gutters, must meet fire rules. Part of our wildfire roofing hub.

LA Roof Guide is an information site only. We do not do roof work.

What the zones are

The LA County Fire Department explains it this way: "While all of California is subject to some degree of fire hazard, there are specific features that make some areas more hazardous." It says CAL FIRE "is required by law to map areas of significant fire hazards based on fuels, terrain, weather, and other relevant factors." These zones "influence how people construct buildings and protect property to reduce risk associated with wildland fires."

The maps sort land into three levels:

• Moderate
• High
• Very high

The City of La Cañada Flintridge notes that the maps use "current data on fuels, fire history, weather, terrain, and other factors" and are typically updated about every ten years.

What changed in 2025

On March 24, 2025, the state Office of the State Fire Marshal issued new recommended maps for Local Responsibility Areas (LRA) in Los Angeles County. These maps cover land within local jurisdictions.

What local officials said at the time:

• Local agencies cannot lower a zone. The LAFD put it this way: "a local agency shall not decrease the level of the FHSZ recommended by the State. However, a local agency may increase the hazard level or make additions."
• The maps must be adopted by ordinance. La Cañada Flintridge reported that "State law requires Los Angeles County to adopt the recommended maps by ordinance within 120 days of their issuance." The LAFD said the City of Los Angeles must also adopt the maps by ordinance.
• More parcels were expected to be affected. The LAFD said it "estimates an increase in the number of parcels that will be affected." It warned the changes "may influence building and vegetation management requirements for properties located within newly classified fire hazard zones."

Zones are not only in the hills. Santa Monica, for example, says "certain neighborhoods are designated as Moderate, High, or Very High Fire Hazard Severity Zones."

How to check an address

CAL FIRE publishes an online map viewer that lets you compare the old and new Local Responsibility Area maps. La Cañada Flintridge and LA County Building and Safety both link to it. LA County Fire also points residents to the CAL FIRE FHSZ Viewer. You type an address and the viewer shows the zone.

A few tips:

• Check the map, then confirm with your city. Each city adopts the maps by its own ordinance and may add areas.
• Note the exact level. Some rules apply only in the very high zone.
• Save a screenshot with the date, for your own records.

What a zone means for a roof

The rules depend on the zone level and on who issues your permit. Two published examples:

City of Los Angeles. The LADBS express reroof permit states: "Class A roof covering is required within Very High Fire Hazard Severity Zone (VHFHSZ)."

LA County Building and Safety. The county's 2026 construction notes apply to "additions, alterations or repairs made to existing buildings within Wildland-Urban Interface (WUI) Fire Area or Fire Hazard Severity Zone." The notes require a Class A roof covering, noncombustible gutters, ember-resistant vents, and more. The county links its notes to a map that shows "moderate to high fire hazard" zones.

La Cañada Flintridge sums it up: properties in high or very high zones "may be subject to California Building Code Chapter 7A" and defensible space rules under Public Resources Code 4291.

Since January 1, 2026, those building rules live in a new standalone code. CALBO describes the 2025 California Wildland-Urban Interface Code, Title 24, Part 7, as consolidating rules "previously located in the California Building Code, California Residential Code, and California Fire Code."

Our Class A roofs, vents and gutters page covers the roof rules in detail.

Defensible space and Zone 0

Fire zone rules also reach the yard around the house. These affect the roof edge too.

• LA County Fire says to "ensure you have up to 100 foot radius of defensible space (cleared vegetation) around your home." It adds that "up to 200 feet of clearance may be required" in some cases.
• Santa Monica describes a "0 to 5 ft 'Zone 0' ember-resistant area around your home." CALBO lists the "Zone 0 ember-resistant perimeter" as a key topic of the new WUI code.
• LA County Fire says to "cut any tree branches within 5 feet of your roof" and to keep branches at least 10 feet from a chimney, with an exception for oak trees.

LA County Building and Safety's notes add that "prior to permitting final approval, the property shall follow the vegetation management requirements."

Before you plan roof work

• Look up the zone for the address.
• Ask your building department which roof rules apply at that zone level.
• Ask whether vents, gutters or eaves must be upgraded as part of the job.
• If you are buying, ask how the zone affects insurance. See insurance in fire zones.

For the permit side, read our reroof permit basics.

This page is general information, not legal, engineering or building code advice. Rules differ by city; check with your local building department and fire department.