The frequency and magnitude of wildfires in the western United States have shown a marked increase over recent years. Concurrently, there has been a significant rise in the destruction of residential and commercial properties due to these fires.

These fires often escalate into catastrophic urban infernos, as seen recently in areas around Los Angeles, the Denver suburbs, and Lahaina, Hawaii. The expansion of urban communities into areas prone to wildfires, combined with climate change, has heightened the risk and frequency of such destructive fires.

Although managing vegetation and other wildland management strategies are crucial for reducing wildfire risks, they alone are insufficient, according to fire safety experts. Kimiko Barrett, a researcher at Headwaters Economics, emphasizes that it is unrealistic and unsafe to assume that firefighters can always protect our homes from fire. In Los Angeles, for instance, despite having one of the most well-prepared firefighting teams, the fire’s spread to buildings was unstoppable once it began, notes Steve Kerber, Vice President and Executive Director of the Fire Safety Research Institute (FSRI), part of UL Research Institutes.

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Experts suggest a fundamental reassessment in our approach to fire risk, advocating for making structures more fire-resistant. “We need a major cultural shift to understand that wildfires are a part of our reality, risks are escalating, and we must adapt to live with this risk,” states Barrett. This involves what some experts refer to as “hardening” homes to make them less vulnerable to fires and prevent initial sparks in urban or suburban settings.

Wildfire risk isn’t confined to the West; areas from the New Jersey Pine Barrens to the Appalachian Mountains also face threats of wildfires escalating into residential areas.

Communities can utilize various certification programs and homeowner guides to improve their fire resistance. These range from voluntary measures led by organizations like the nonprofit Insurance Institute for Business and Home Safety (IBHS) to state or local building code initiatives. “The underlying science is universal across these recommendations,” states Anne Cope, chief engineer at IBHS.

Understanding House Fires

A house can be threatened by wildfires in three primary ways: through embers, direct flame contact, and radiant heat.

“Embers pose the greatest risk,” explains Karl Fippinger of the International Code Council. These embers can travel miles ahead of a wildfire, and if they lodge in vulnerable spots like eaves or cracks, they can ignite a home, leading to total loss in 90% of cases.

Direct contact with flames is clearly dangerous, as combustible materials around a home can lead to fire spread. Radiant heat from neighboring fires can ignite nearby vegetation and even break windows, allowing embers to enter a home.

Defining Wildfire Resistance

The term “wildfire-resistant” can vary but essentially means making a home less likely to catch fire from embers, direct flames, or radiant heat, thereby giving residents more time to evacuate and for firefighters to respond.

Some fire-resistance strategies can be retrofitted affordably and easily, while others might require more significant investment. However, building new homes with fire-resistant materials typically costs about the same as traditional methods and can offer additional benefits like improved energy efficiency or wind protection.

Creating a Defensible Space

Defensible space is a key strategy in fire prevention, involving the management of vegetation and other flammable materials around homes to reduce fire risk. This space not only helps protect individual homes but can also mitigate risk for entire neighborhoods.

Important considerations within this space include the flammability of plants and other materials such as mulch, and structures like fences and decks. Noncombustible materials and strategic landscaping can significantly reduce fire risks.

Exploring Fire-Resistant Windows

Research by FSRI has shown that dual-paned windows with tempered glass and noncombustible frames, such as aluminum, are most effective at resisting fire. These windows also contribute to energy efficiency, which parallels their ability to insulate against fire.

Fire shutters can also provide substantial protection for windows against heat and embers, similar to the storm shutters used in hurricane-prone areas.

Identifying the Safest Roofing Materials

The safest roofing materials are simple in design and made from noncombustible materials such as metal or asphalt. Regular maintenance to remove debris and the installation of protective gutter covers are additional preventive measures.

The Importance of Community-Wide Fire Resistance

Effective wildfire resistance requires a comprehensive approach at both the individual and community levels. Community-wide building codes and defensible space regulations are essential, although enforcement and compliance can be challenging.

Change can be difficult, but as seen in hurricane-prone areas, rebuilding to higher standards can significantly reduce future damage and loss.

For more detailed guidance on making homes wildfire-resistant, refer to public resources from organizations like Cal Fire and IBHS.

Editor’s Note (3/19/25): This sentence was edited after posting to clarify that the Fire Safety Research Institute is a part of UL Research Institutes.