Learn about the data sources used to determine fire damage estimates.
The data used to determine a home’s vulnerability to wildfire primarily comes from the First Street Foundation Wildfire Model and Arup Corporation, with additional property data provided by the National Structures Inventory (NIS) database, the National Agriculture Imagery Program (NAIP), and from Lightbox.
Data sources used
The First Street Foundation Wildfire Model has developed a method to estimate a home’s wildfire vulnerability. Vulnerability estimates are based on a property’s risk of wildfire exposure, ignition likelihood, fire intensity, and exposure to embers; and building characteristics such as the size of the structure, slope of the property, materials, and building value.
Please note that fire damage estimates are not included in determining a property’s Fire Factor®, which is indicative of its probability of exposure to wildfire only.
- Property locations are estimated from remotely-sensed imagery and public records by MapBox. These locations were used with public real estate and tax assessor records provided by Lightbox to associate building footprints with property parcels.
- Building characteristics for each property come from Lightbox, a leading provider of commercial real estate data. Where building characteristic data was not recorded, it was estimated based on known building characteristics and similarities with nearby properties.
- Slope and aspect of the property under the building were computed from the United States Geological Survey National Elevation Dataset (USGS NED).
- Projected flame lengths, ignition likelihood, and embers exposure come from the First Street Foundation’s Wildfire Model.
Additionally, “fragility curves” developed by Arup Corporation were applied to the First Street Foundation Wildfire Model to determine the damage a home may sustain based on its vulnerability and location.
The First Street Foundation National Wildfire Model is a first-of-its-kind, nationwide, behavioral wildfire model that shows a specific location’s probabilistic risk of wildfire based on the vegetation, topography, and fire weather in the surrounding area. It builds off of decades of peer-reviewed research and forecasts how wildfire risks will change over time due to changes in the environment. Use Risk Factor™ to find property-specific wildfire risk assessments for any U.S. address.