Fire season: defensible space and fire zones

Defensible space

For a building in the State Responsibility Area, California's defensible space rules and their exceptions are in Public Resources Code §4291; in a Very High Fire Hazard Severity Zone that a local agency has designated, they are in Government Code §51182.

Sources: California Public Resources Code §4291; California Government Code §51182

Find the zone for a property

The State Fire Marshal's Fire Hazard Severity Zone page links to a map viewer of the zones.

In State Responsibility Areas there are three hazard levels: moderate, high and very high.

Source: Office of the State Fire Marshal: Fire Hazard Severity Zones

The 5-foot ember-resistant zone

The ember-resistant zone within 5 feet of a building, counting any attached deck as part of the building, is set out in Public Resources Code §4291, and its details are left to the Board of Forestry and Fire Protection's regulations.

Under that section, the requirement for the zone (“Zone 0”) does not take effect for new buildings until the Board updates its regulations and its guidance document, and it takes effect for existing buildings three years after that.

The Board adopted emergency Zone 0 rules on August 19, 2026. The Office of Administrative Law lists that filing as withdrawn on September 8, 2026, and on September 24, 2026 the Board's page said it was still working with that office on a final review.

Sources: California Public Resources Code §4291; Board of Forestry and Fire Protection: Defensible Space Zones; Board of Forestry and Fire Protection: Notice of Proposed Emergency Action, Zone 0 Defensible Space (August 20, 2026, PDF); Office of Administrative Law: Recent Actions on Emergency Regulations