Journal Article Presents Modeling of Wind-Driven Building-to-Building Fire Spread
The peer-reviewed journal article “Wind-Driven Building-to-Building Fire Spread: Experimental Results and Probabilistic Modeling” has been published in the Fire Technology journal. The article is co-authored by Daniel Gorham, a research engineer for UL Research Institutes’ Fire Safety Research Institute, and researchers from the Insurance Institute for Business & Home Safety.
Wind-Driven Building-to-Building Fire Spread
Traditionally, fire is modeled in growth, steady, and decay phases, with measurements such as peak heat flux or long-duration heat load used to predict fire spread. However, real-world evidence shows that while target structures experience increasing heat exposure as the fire intensity builds, that intensity drops abruptly if the source structure collapses during the growth phase. This results in a weakened correlation between observed damage and the traditional metrics, highlighting the need for a more accurate framework to determine the separation distance at which resilient building materials can meaningfully resist the progression of a conflagration. This study sought to do so through a comprehensive analysis of wind-driven building-to-building fire spread in full-scale tests.
Improving Probabilistic Frameworks
To study the interconnectedness of exposure intensity, duration, and material response, 23 full-scale tests were conducted under varied wind speeds, separation distances, and material configurations, using a test structure that represented a California Building Code Chapter 7A-compliant home. The full range of fire damage classifications — No Damage, Cosmetic Damage, Envelope Damage, or Destroyed — was mapped to statistical distributions of energy exposure over an intermediate timescale, which better reflects material response under realistic fire conditions.
The resulting probabilistic framework enables risk-informed decision-making, allowing engineers to assess vulnerability and survivability under variable exposure conditions rather than binary “ignited/not-ignited” outcomes. At a separation distance of 10 ft (3 m), the tested building materials showed minimal likelihood of survival when exposed to fires from large, fully loaded sheds. However, at a distance of about 20 ft (6 m), exposure levels dropped enough that wildfire-resistant building components have a fighting chance, and by 30 ft (9 m), the probability of survival increased substantially.
About the Fire Technology Journal
Fire Technology is a scientific journal that publishes original contributions, both theoretical and empirical, that contribute to the solution of problems in fire safety science and engineering. It is the leading journal in the field, publishing applied research dealing with the full range of actual and potential fire hazards facing humans and the environment. It covers the entire domain of fire safety science and engineering problems relevant in industrial, operational, cultural, and environmental applications, including modeling, testing, detection, suppression, human behavior, wildfires, structures, and risk analysis.
