Wildfires directly threaten human lives and properties in the wildland-urban interface (WUI). The quantity of combustible materials within houses is critical, yet variability in house fuel load remains unaccounted in current WUI fire modelling. This study integrates House Fuel Load (HFL) into the Streamlined Wildland–Urban Interface Fire Tracing (SWUIFT) simulation framework to examine its influence on WUI fire spread. HFL assessments were derived from computer-vision assessment of structural attributes and combined with standardized indoor fuel load values to calculate fully developed fire durations of ignited structures. We compared a baseline SWUIFT runs (fixed fire-duration configuration) with HFL-coupled cases under two pHRR scenarios of 100 kW/m 2 and 150 kW/m 2 in simulations of the 2023 Lahaina fire. Results indicate that although varied HFL modifies the theoretical heat release of individual structures, the WUI fire spread patterns and ignition statistics remain largely consistent. Sensitivity analysis further indicates that reducing burning time below 60 minutes substantially inhibits fire spread, whereas durations beyond 100 minutes have limited additional influence. Overall, the HFL-based method provides reasonable estimates of residential burning time, and the corresponding simulated fire spread paths align closely with the real event, supporting the applicability of the approach. • CV-derived house fuel loads (HFL) were integrated into SWUIFT fire spread simulation. • AI provides more accurate structure burning durations enhancing fire spread predictions. • Fire spread tends to a steady state once the structural burning duration exceeds a threshold. • Simulated fire spread paths align with 2023 Lahaina Fire, demonstrating its applicability.
Ding et al. (2026) studied this question.