Zero Flame Spread: Hardening Structures and Parcels from Wildfire

The Zero Flame Spread Project, led by Southern California Edison, tackles the rising wildfire threat in the Wildland-Urban Interface (WUI) by advancing fire-resilient building practices. The Project Team identified effective fire-resistant materials—like fire resistant stucco, mineral wool insulation, and fire-rated windows—and validated their performance in a full-scale burn test where a hardened structure withstood 60 minutes of direct flame and radiant heat.

The project also introduced the Hazard Mitigation Methodology (HMM), which promotes ember hardening, structure separation, and fuel management to reduce wildfire risk, especially in dense communities. The Parcel Assessment for Wildfire Hardening (PAWH) form offers a practical way to assess and improve property-level resilience. While some upgrades, such as fire-rated glazing, are costly and may challenge energy code compliance, materials like fire resistant stucco provide a cost-effective balance. A recent update to California’s Title 24 now prioritizes fire safety over strict energy limits in high-risk zones, supporting broader adoption of these protective measures