As part of our Rebuilding After Wildfire initiative, we’re introducing a new companion series: Built to Endure. This series breaks down the materials and construction strategies that make homes stronger and safer—starting at the top, with roofs and eaves.
When wildfires strike, flames may never reach your doorstep—but embers will. Carried by the wind, they can travel miles and sneak into small gaps in siding, vents, and rooflines. That’s why the exterior walls of your home aren’t just about looks—they’re your first line of defense.
In this second installment of our Built to Endure series, we’ll explore how smart material choices and thoughtful detailing can transform your walls into a resilient barrier—one that doesn’t just stand strong, but shields your home from the heat, sparks, and chaos of wildfire.
Research shows that flying embers, not direct flames, are the cause of most home ignitions during wildfires.
Walls do more than define your home's style—they help protect it from:
Fire-resistive walls should be designed to:
Choosing the right exterior wall materials—and assembling them correctly—is one of the most impactful steps you can take to improve your home’s fire resilience. In fire-prone regions, the exterior shell of a building becomes the first line of defense. The materials you select can mean the difference between a home that resists ignition and one that fuels a fire’s spread.
Fire-resistant materials work in two key ways: they either do not ignite easily or they are slow to combust, allowing time for emergency response and evacuation. Non-combustible options such as stucco, fiber cement, brick, stone, and specially treated wood sidings have proven effective in wildland-urban interface zones. These materials, when paired with robust construction methods—like fire-stopping barriers, tight joints, and minimal vents—create a continuous protective envelope.
But it’s not just about material selection. The system matters. Even the best material can fail if installed improperly or combined with flammable insulation or backing. Detailing is critical: for instance, ensuring that junctions between walls, roofs, and foundations are sealed and that overhangs or vents are protected with metal mesh can prevent embers from infiltrating vulnerable areas.
Here’s a breakdown of some of the most trusted materials used in wildfire-prone regions. Each offers a different balance of performance, cost, maintenance, and design flexibility - in no particular order of importance:
The best materials won’t protect your home if they’re installed poorly. Fire resilience isn’t just about what you use—it’s about how every component works together. Make sure your team pays close attention to:
Your final choices will depend on budget, architectural style, and long-term performance goals. Work closely with your architect and builder to evaluate material assemblies that reflect both your design vision and the realities of life in a wildfire-prone region. These decisions may be invisible once the house is complete—but they’re critical to its future.
In Part 3, we’ll explore how to protect a home’s most fragile components—windows and doors—and how to prevent heat and embers from breaching the interior envelope.