Orange County, CA Fire Regulations: Wildfire Zones (2026)
Key Facts
- Zone classifications
- Moderate, High, Very High Fire Hazard Severity Zones (CAL FIRE)
- Updated OC unincorporated map
- Released by CAL FIRE in 2025
- High-risk canyon communities
- Silverado, Williams, Modjeska, Trabuco
- Defensible space in zones
- Up to 100 ft under PRC 4291
- Building rules
- Stricter WUI construction standards in higher zones
- Sale disclosure
- Defensible Space Disclosure required (Civ. Code 1102.19)
Summary
Much of unincorporated Orange County - especially the Silverado, Modjeska, and Trabuco canyon communities - lies in CAL FIRE-designated Very High, High, or Moderate Fire Hazard Severity Zones. CAL FIRE released an updated FHSZ map for OC's unincorporated areas in 2025. Properties in these zones face stricter defensible-space, building, and disclosure requirements.
The State Fire Marshal is mandated to classify lands within State Responsibility Areas into Fire Hazard Severity Zones (FHSZ). Fire Hazard Severity Zones fall into one of the following classifications:
Moderate
High
Very High
The California laws that require Fire Hazard Severity Zones include California Public Resources Code 4201-4204, California Code of Regulations Title 14, Section 1280 and California Government Code 51175-89.
Frequently Asked Questions FAQ Document (PDF)
FAQ Document (PDF) (Spanish)
Examples of FHSZ State Minimum Mitigation Requirements
Explore Fire Hazard Severity Zones
The Fire
Full Breakdown
CAL FIRE (the California Department of Forestry and Fire Protection) classifies land by wildfire risk into Moderate, High, and Very High Fire Hazard Severity Zones (FHSZ). CAL FIRE released an updated Fire Hazard Severity Zone map for the unincorporated areas of Orange County in 2025, using the latest climate data, fire history, topography, and wildfire modeling. The canyon communities of Silverado, Williams Canyon, Modjeska, and Trabuco - all served by OCFA - sit in mapped fire-hazard zones, and the 2020 Bond Fire burned through this area, underscoring the risk.
Buildings and properties in higher FHSZs face more stringent requirements for both building construction (wildland-urban interface materials) and vegetation maintenance. 19. OC Public Works and OC Development Services publish the Very High Fire Hazard Severity Zone map used to apply these building and vegetation rules, and OCFA provides an interactive tool for residents to find their FHSZ designation and request defensible-space inspections.
Violations & Fines
Wildfire-zone rules are enforced through building-permit review (stricter construction standards in higher zones), defensible-space inspections by OCFA, and disclosure requirements at sale. Failure to maintain PRC 4291 defensible space in a designated zone can lead to abatement notices and citations; a seller who cannot provide a compliant Defensible Space Disclosure (Civ. Code 1102.19) may be unable to close escrow.
Frequently Asked Questions
Is my unincorporated Orange County property in a fire hazard zone?
What extra rules apply in a Very High Fire Hazard Severity Zone?
Who designates these zones?
Sources & Official References
Other rules in Orange County
California rules heatmap·Compare Orange County to another location·View the California fire regulations overview
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