Stop, Drop, and Insulate: How SPF Can Protect Homes from Wildfires
The Ember Threat: Small Sparks, Big Danger
Embers — tiny pieces of burning debris — are responsible for the majority of home ignitions during wildfires. These glowing particles can be carried by the wind for miles, landing on:
- Roof shingles
- Eaves and soffits
- Attic vents and crawlspaces
They often spark fires long before the main blaze arrives. In fact, it’s estimated that 90% of homes destroyed in wildfires are due to ember intrusion, not direct flame contact.
This alarming fact emphasizes the importance of ember-resistant home design and insulation.
California Building Code Updates (2022)
Thanks to the work of organizations like the Institute for Business and Home Safety, new regulations have strengthened home wildfire defenses. The 2022 California Building Code (Section 706.1A) now requires:
- Ember-resistant roof vents
- Alternative attic venting systems
- Reinforced materials in high-risk WUI zones
Local governments are also increasing public outreach to educate homeowners about these changes.
How Spray Foam Insulation (SPF) Helps
SPF isn’t just about energy efficiency — it plays a critical role in wildfire protection:
Seals attic spaces and other openings to block ember intrusion Reduces toxic smoke from entering interior spaces Enhances R-value stability, moisture resistance, and acts as a secondary water barrier Provides wind uplift resistance during extreme weather
According to Dr. Joe Lstiburek, a respected voice in building science, wildfire safety depends on two things:
- Preventing ignition from embers and vegetation
- Preventing fire spread from exterior to interior
SPF supports both goals by sealing and strengthening the structure where it’s most vulnerable — roofs, walls, and attics.
Takeaways for Contractors and Homeowners
If you’re a homeowner in a wildfire-prone area, or a contractor building in WUI zones, SPF offers peace of mind that goes far beyond comfort:
- Homeowners: Ask about SPF as part of any roof or attic upgrade.
- Contractors: Highlight wildfire protection as a key SPF benefit.
“SPF isn’t just about insulation — it’s a crucial tool in wildfire preparedness.”
Sources
- Institute for Business and Home Safety
- “Small Wandering Embers Play a Big Role in the Spread of Wildfires”, Holly Farmer, ProBuilder, January 2025
- Building Science Corporation