The devastating North American wildfire seasons of 2017 and 2018 proved to be a pivotal point in the insurability of property against this risk. The tens of billions of insured losses led to soaring premiums and the withdrawal of underwriters in many regions, notably California.

Properties located in the wildland-urban interface (WUI) are most at threat from wildfires, and it's communities in these locations that Xyloplan is helping with an innovative wildfire model that helps identify, quantify and mitigate the risk of losses.

Traditional wildfire modelling was developed by the US Forest Service to understand the threat to commercial forestry and focuses on wildfire intensity. But in WUI communities, the threat comes from fast-moving, wind-driven fires outpacing the ability of firefighters to respond.

In contrast, XyloPlan's wildfire model recognises how wildfires spread – through three different vectors of burning vegetation, from vegetation to buildings, and from building to building – and how the survivability of structures is intrinsically linked to the conditions that surround a property, how fires can enter a community, home hardening efforts and the local firefighting response.

The assessment includes multiple weather scenarios, which are derived from analysis of historical weather observations in the region and are used to identify wind, relative humidity and fuel moisture parameters for historically accurate wind events.

The model also generates "ember threat zones", based on ember flight physics to assess areas likely to be exposed to high-density ember showers before and during fire arrival.

The Fire Pathways model allows insurers to assess risks at the community and parcel-specific level, to assist with underwriting, portfolio construction and risk aggregation. These risk assessments are informed by current conditions, including the mitigations that communities have implemented.

The model can also be used by communities to prioritise and optimise mitigation efforts by identifying how fires encroach on properties and which measures result in the largest increase in arrival times, therefore giving firefighters a greater chance to stop the blaze.

The judges commended XyloPlan for its consideration of mitigation and disaster-response efforts as part of an innovative approach to modelling the spread of fires.