Fast fires accounted for 2.7% of U.S. wildfires but destroyed 78% of structures lost
Key Takeaways
- •Research led by Virginia Iglesias projects that annual U.S. structures damaged or destroyed by wildfire could nearly triple by mid-century, with up to 449,000 structures lost between 2026 and 2060 if no additional risk-reduction action is taken.
- •The 2026 western fire season brought record heat, historically low snowpack, more than 318,000 acres burned in Colorado by late October—nearly double the state's post-2000 annual average—and 48 consecutive days at the highest national firefighting preparedness level.
- •Fast fires, defined as burning more than 4,000 acres in a single day, represented only 2.7% of fires analyzed from 2001 to 2020 yet accounted for 78% of destroyed structures and 61% of firefighting costs.
- •Development in the country's highest wildfire-risk areas expanded tenfold from 1945 to 2015, and approximately one-third of western neighborhoods facing the greatest future risk are low-income communities.
- •Meeting the two protection levels in Colorado's fire code raises minimum new-home construction costs by only about 0.6% and 4.2%, indicating wildfire-resilient building is less expensive than many expect.

Wildfire-related damage to homes and other structures across the United States is on pace to nearly triple by mid-century as temperatures rise and development expands, according to new research by Virginia Iglesias and her colleagues. The 2026 wildfire season has underscored that risk and the growing importance of making homes and properties less vulnerable to fire. Many measures that reduce the risk of losing a home do not have to be prohibitively expensive.
A severe 2026 western fire season
The 2026 wildfire season began across much of the West with historically low mountain snowpack, early snowmelt and exceptional warmth. Fires were already breaking out before the nation’s hottest summer on record intensified drought and dried vegetation.
Colorado’s Aspen Acres Fire destroyed hundreds of structures in June. In July, four firefighters died from injuries sustained when the fast-moving Knowles Fire overtook them near the Colorado–Utah border. In August, wind-driven fires reached neighborhoods in Spokane, Washington, damaging more than 800 homes and forcing tens of thousands of residents to evacuate.
Rain during Colorado’s summer monsoon season helped firefighters gain ground. Across the Rocky Mountain region, lightning continued to ignite fires, but rainfall helped keep many fires small despite above-average temperatures.
The reprieve did not prevent Colorado fires from burning more than 318,000 acres by late October, nearly twice the state’s annual average since 2000. Nationally, the area burned was also well above average. The U.S. spent 48 consecutive days at Preparedness Level 5, the highest level and an indication that firefighting resources were stretched nationwide. The 10-year annual average is 25 days.
Why wildfire risk is rising
Fire is a natural and often beneficial part of many ecosystems, where it shapes vegetation and supports biodiversity. But a century of fire suppression has allowed dry vegetation to accumulate in forests that historically burned frequently.
Human-caused warming, including warming linked to fossil-fuel combustion, has increased the rate at which the atmosphere draws moisture from land. That process dries soils and vegetation. Researchers estimate that this drying nearly doubled the area burned in western U.S. forests between 1984 and 2015 compared with the area that would have burned without human-caused climate change.
More people are also living in and near wildland areas, increasing the chance that fires will reach neighborhoods. Human activity has extended the fire season beyond summer, when most lightning-caused fires occur. Power lines, vehicles, machinery, debris burning and campfires can ignite fires throughout the year.
Together, these factors have helped nearly quadruple the annual area burned in the western United States since 2000. They have also contributed to the growing threat from fast-growing fires that can overwhelm emergency response systems.
In a 2024 study, Iglesias and her colleagues used satellite imagery to measure daily fire growth across the contiguous United States from 2001 through 2020. They defined “fast fires” as fires that burned more than 4,000 acres in a single day. Those fires accounted for only 2.7% of the fires analyzed, but they were responsible for 78% of documented structures destroyed and 61% of reported firefighting costs.
A short period of rapid growth, often driven by strong winds or highly flammable materials, can have major consequences even when a fire’s eventual size is relatively limited. In many ecosystems, fires are also becoming faster.
More people and buildings in danger
The number of people and buildings exposed to wildfire in the United States has increased, adding to the potential for damage. From 1945 to 2015, development in areas with the country’s highest wildfire risk expanded tenfold. That growth increased human exposure while adding ignition sources and buildings that can burn.
Once embers enter a neighborhood, flames can spread rapidly from one building to another. New research by Iglesias’ team indicates that, without additional action to reduce wildfire risk, the annual number of structures damaged or destroyed nationwide could nearly triple by mid-century. The research estimates that as many as 449,000 structures could be lost between 2026 and 2060.
The researchers reconstructed historical fire risk using data on development patterns, the area burned by wildfires and the effects of those fires. They then modeled future risk using expectations for weather, climate and housing density.
The study found that approximately one-third of western neighborhoods facing the greatest future risk are low-income communities. Residents in those communities may have difficulty paying for measures to protect their homes, maintaining insurance coverage and recovering financially after a fire.
Measures to reduce the risk
The projections indicate a serious potential loss, but actual damage will depend in part on decisions made now. Homes can be made less likely to ignite by installing Class A fire-resistant roofs — the highest fire-resistance rating for roofing materials — and ember-resistant vents, which reduce the chance that burning particles will enter a building.
Removing flammable debris, mulch, firewood and vegetation from around buildings can also reduce the chance that a fire will spread to a home. In many areas, community programs help low-income homeowners reduce wildfire risks to their properties.
Wildfire-resilient construction may cost less than many people expect. In a study of new home construction, Iglesias and her colleagues found that meeting the two protection levels established by the Colorado fire code increased minimum construction costs by approximately 0.6% and 4.2%. Lower-cost materials and homeowner education can make resilience measures more accessible.
These construction measures can reduce, but not eliminate, the risk of losing a home. Beyond individual buildings, prescribed burns and appropriately designed forest-thinning operations can reduce fuel and change fire behavior before flames reach neighborhoods.
Utilities can reinforce infrastructure and reduce the likelihood of ignition while limiting disruptions from preventive power shut-offs. Insurance companies can reward measurable risk reduction and help preserve coverage in communities working to become safer. These approaches are most effective when used together.
A home’s risk depends on its construction, its immediate surroundings and the wider neighborhood. There is no single solution that applies to every community. As wildfire threats grow, strategies tailored to each area’s environmental, social and economic circumstances will become increasingly important. Because the study’s projections assume no additional risk-reduction action, how quickly communities, utilities, insurers and building-code officials adopt these strategies will help determine whether losses follow the trajectory the research describes.
Virginia Iglesias is Earth Lab Director at the University of Colorado Boulder.
This article was republished from The Conversation under a Creative Commons license. The original article is available at The story was originally featured on Fortune.com at https://fortune.com/2026/11/07/fast-fires-wildfires-structures-lost-449000-by-2060/.