SMAR Daily Industry News

Why Pricing Wildfire Risk Isn't Enough for Homeowners

Recent wildfires in Spokane, Washington, highlighted a shift in how fire spreads through communities. Strong winds drove flames across a supermarket parking lot, where the lack of vegetation did not stop the fire; instead, cars, plastics and other everyday items became fuel, turning the built environment into a conduit for the blaze. The fires damaged or destroyed nearly 1,000 buildings, leaving families homeless and underscoring the limits of traditional defensible-space strategies.

The pattern seen in Spokane mirrors earlier events such as the 2025 Palisades and Eaton fires, the 2024 Jasper fire and the 2023 Lahaina fire. In each case, extreme fire behavior and wind-driven embers caused simultaneous ignitions, overwhelming suppression capacity and converting structures into fuel sources. Once a neighborhood ignites, the challenge shifts from preventing vegetation from reaching a home to preventing one burning property from igniting the next.

Key contributors to this new fuel load include home-mounted lithium-ion batteries, which can generate heat fluxes of 40 to 120 kilowatts per square meter when they ignite against siding, and electric vehicles. Peer-reviewed data from six full-scale EV fire experiments showed a midsize EV burning five feet from a wall produced 58 kilowatts per square meter, exceeding the heat tolerance of the strongest tempered-glass glazing required by the Insurance Institute for Business & Home Safety. Wooden fences, decks, outdoor furniture, boats, hot-tub covers, firewood stacks and piles of delivery packages also add significant radiant heat, with burning wood fences potentially exposing siding to nearly twice the heat that initiates wood smoldering.

While hardening measures such as ember-resistant vents, defensible space and fire-resistant building materials remain essential, the IBHS Wildfire Prepared Home standard does not fully account for these dynamic fuel sources. The standard evaluates individual components against prescribed exposures, yet real-world fires test an entire property against whatever is burning nearby. At the setbacks permitted by IBHS, common fuels can produce radiant heat that exceeds the performance limits of hardened assemblies, and for some assemblies no performance rating exists at all.

Given the growing scale of fire events and strained mutual-aid resources, the industry is looking toward active defense solutions. External, standalone sprinkler systems have proven effective; during Minnesota’s 2007 Ham Lake Fire, 98% of structures protected by sprinklers survived, according to a University of Minnesota report prepared for the Firewise Program. The U.S. Forest Service and National Park Service also routinely deploy temporary sprinkler systems during wildfires, extending firefighting tactics to properties without on-site crews.

The emerging consensus is that risk analysis must assume wildfire exposure for properties in fire-adapted landscapes, accounting for direct flame, radiant heat and ember impacts. Hardening improves baseline resilience, but without responsive capabilities it cannot fully protect homes when surrounding fuels ignite. Active defense technologies, such as remotely triggered sprinkler systems, may become a critical complement to traditional mitigation as fire seasons lengthen and suppression resources remain stretched.

Why it matters

Insurers need to reassess underwriting models to reflect the growing risk from non-vegetation fuels and the need for active fire-defense technologies.

FAQ

What fuels contributed to the rapid spread of the Spokane wildfires?
Cars, plastics, lithium-ion batteries, electric vehicles, wood fences, decks, outdoor furniture, boats, hot-tub covers, firewood stacks and delivery packages acted as fuel.

How effective were temporary sprinkler systems in past wildfires?
During Minnesota’s 2007 Ham Lake Fire, 98% of structures protected by sprinklers survived.

What heat flux levels were measured for burning lithium-ion batteries and EVs?
Lithium-ion batteries produced 40 to 120 kilowatts per square meter; a midsize EV produced 58 kilowatts per square meter at five feet distance.

Why does the IBHS Wildfire Prepared Home standard fall short?
It does not fully account for dynamic fuel loads around modern homes and evaluates components rather than the entire property exposure.

Source: Insurance Journal. See the original source for full details.