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Escalating wildfire threats have placed a spotlight on the need for innovative home building solutions. From design and land planning to fire-resilient building methods and materials, these solutions should be top of mind for builders, especially in wildfire prone areas.

At PCBC 2024, one of the education tracks for June 19 will focus on wildfire resiliency. The track, produced in partnership with the Insurance Institute for Business & Home Safety (IBHS), will include presentations from leading experts and a live burn demonstration.

IBHS is a nonprofit research organization that studies ways to strengthen homes and businesses to prevent damage from severe weather and wildfire. Steve Hawks, senior director for wildfire at IBHS, shares more on wildfire risks and resiliency—and the live demo—below.

How can home builders begin mitigating wildfire risks when planning for a project?
Each new home built in California is an opportunity to ensure the housing stock of the future is better prepared for the wildfire risk it faces. And doing so can be affordable. A study released by Headwaters Economics and the Insurance Institute for Business & Home Safety (IBHS) found vulnerable areas of California homes can be mitigated during new construction for less than $3,000.

What makes a home wildfire resilient?
We can’t stop wildfire, but we can make homes more wildfire resilient. Research shows embers are the leading cause of ignition during a wildfire and once a home ignites, there is more than a 90% chance it will be destroyed without firefighter intervention. The combination of defensible space and increasing the resilience of the exterior materials of the home to embers, radiant heat, and direct flame exposure meaningfully reduces the wildfire risk to a home.

In contrast, what makes a home high/extreme risk of wildfire?
A home is at a higher risk of wildfire when the five-foot buffer immediately surrounding it contains vegetation, wood mulch or combustible materials which can ignite when embers land there. This includes wood and vinyl fencing, posts and gates within that 5-foot zone that can serve as a wick and provide a pathway for fire to reach the home. Additionally, a home built with components and materials like wood shake roofing, combustible siding, and single pane windows make the home more vulnerable.

What are three key points of the Wildfire Prepared Home program?
Based on the latest IBHS wildfire research, Wildfire Prepared Home is the first-ever wildfire mitigation designation program. It addresses three areas of a home that are vulnerable to ember attack: 1) the roof, 2) exterior features and 3) the five-foot buffer surrounding a home.

Designation requirements include having a Class A roof (which most California homes have), addressing exterior features such as ember-resistant vents and ensuring the five-foot buffer surrounding the home is completely free of combustible materials.

Wildfire Prepared Home Plus is most often achieved with new home construction and adds an extra layer of protection by requiring additional mitigations such as enclosing eaves, having noncombustible siding, and upgrading to fire-resistant windows to protect against radiant heat and direct flame contact.

Are there any common misconceptions surrounding wildfire resiliency?
A common misconception surrounding wildfire resiliency is that you can take just one or two actions to prepare for a wildfire. Wildfire, like many perils, will find the weakest link to ignite a home, so it takes a collective system of actions to meaningfully reduce a home’s risk of wildfire.

Can you share more on the IBHS Wildfire Prepared Home demo that is scheduled for PCBC?
Firefighters will use drip torches to set small spot fires – representing burning embers – in the wood mulch around side-by-side structures: an unmitigated home and mitigated home built to the Wildfire Prepared Home standard. On the unmitigated or typical construction/landscaping side, the wood mulch will be within the five-foot buffer around the home while all combustible materials for the Wildfire Prepared Home will be outside of this area known as Zone 0. The wood mulch around the unmitigated house will ignite the vegetation and in turn, the wood fencing and eventually the house itself, starting at the exterior walls and then engulfing the eaves and roof. During this process, the window glass will break, and the vinyl frame will melt, causing the window to fall out. At the end of the demonstration, the unmitigated structure will be destroyed. On the Wildfire Prepared Home, the burning wood mulch will ignite the vegetation but because these items are outside of Zone 0, the spot fires will eventually die out and there will be no impact to the structure, which will be left standing intact at the end of the demonstration.

What will attendees be able to learn from the demonstration?
Attendees will see in real-time how defensible space and home hardening techniques can reduce a structure’s risk of wildfire. The demo shows how critical it is to maintain a noncombustible Zone 0 and provides a real-life example of how that can be done without losing curb appeal.

Are there any new findings surrounding wildfire mitigation techniques that you’d like to share?
Our research continues to fill gaps in knowledge on how wildfires impact buildings. We are examining the relationship of structure-to-structure fire spread to see how far apart new construction is needed to avoid fire spreading between buildings. IBHS is looking at structure separation distances, building orientation, and building materials to determine science-based mitigation techniques for building more resilient properties. Research is also focused on plant flammability for a better understanding of what types of vegetation are better adapted for our built environment. In addition to parcel-level mitigations, IBHS is examining community-level mitigations to break the cycle of loss in neighborhoods around the country.