Solano County, CA Fire Regulations: Wildfire Zones (2026)

Fire Hazard Severity Zones in Solano County are split between two responsibility categories. CAL FIRE LNU is the State Responsibility Area (SRA) agency: SRA covers most rural and wildland portions of the county and is mapped under PRC §4201 et seq. The Local Responsibility Area (LRA) is everything inside city boundaries plus areas where the County or a local fire district provides primary structural protection; LRA FHSZ maps were updated by the Office of the State Fire Marshal on February 24, 2025 and adopted locally. Within SRA, all three classifications (Moderate, High, Very High) trigger PRC §4291 100-foot defensible space and California Building Code Chapter 7A wildland-urban-interface (WUI) construction standards for new construction and substantial remodels — ignition-resistant exterior siding, ember-resistant vents, Class A roofing, decking, and dual-pane tempered windows. Within LRA, only the Very High FHSZ historically triggered the same standards; the updated 2025 maps expand mapped Moderate and High zones, and Solano County's adopted ordinance now extends building requirements as listed in its Chapter 6.3 amendments. Real-estate transfer disclosures under California Civil Code §1103 require sellers to disclose if a property is in a designated SRA or VHFHSZ. The 2020 LNU Lightning Complex fires (which originated in Solano and adjacent counties on Aug 17, 2020 and ultimately burned ~363,000 acres) drove this expanded mapping effort.