Can We Know Which Homes in California Will Burn?

As one of the worst wildfires in California history continues to extend the state’s worst wildfire season, Faith Kerns at The Conversation notes that which houses burn and which don’t is more predictable that it may seem.

While “[i]t is commonly thought that it takes direct flame to spread a fire,” she writes, it’s often embers that are to blame.

“These small bits of burning debris can be lofted long distances by the wind. They can then end up igniting landscaping materials like combustible mulch, or enter homes through vulnerable spots – gutters teeming with debris, unscreened attic vents, open or broken windows, old roofs with missing shingles.”

The damage to homes is also deeply affected by whether or not those areas are thought to be at risk, and whether or not building codes reflect that. Measures to decrease the damage to homes caused by wildfires can include regulations on building materials and building codes.

"Researchers recommend what is known as a “coupled approach” to home and building survival. This means the development and maintenance of an effective defensible space, as well as the careful selection of construction materials and correct installation to ensure that, for example, there are not gaps in siding or roofing that would allow embers to penetrate."

But in a state where there’s usually a building boom somewhere, the most effective method of prevention is also the most painful.

“Decision-makers also need,” Kerns writes, “to be willing to take on the most taboo topic of them all: recognizing that there are places houses simply shouldn’t be built, or rebuilt, at all.”

Seasonal wildfires have always part of the ecology of much of California, but they are becoming more frequent and more intense, in part due urban sprawl (the Wildland-Urban Interface) and in part due to climate change.

“It’s not something that we should, or ever could, hope to fully contain,” Kerns writes. “Our only chance is learning, really and truly and finally learning, to live with it.