Aluminum wrap used to protect homes from California wildfires
RENO, Nevada – Martin Diky said he panicked when a massive wildfire started rolling down a slope toward his wooden house near Lake Tahoe.
The contractor had time to do some quick research and decided to wrap his mountain house with protective aluminum siding. The material that can withstand intense heat for short periods resembles the aluminum foil in the kitchen drawer, but is inspired by the tent-shaped shelters that wildland firefighters use as a last resort to protect themselves when trapped by the flames.
Diky, who lives mostly in the San Francisco Bay Area, purchased $ 6,000 of packaging from Firezat Inc. in San Diego, enough to cover his 1,400-square-foot (130-square-meter) second home. ) at the edge of the small California community of Meyers.
“It’s quite expensive, and you would feel stupid if they stopped the fire before it closes,” he said. “But I’m really glad we did. It was quite nerve-racking as the flames descended the slope.
The flexible aluminum foil that Diky affixed to his $ 700,000 house is not widely used because it is expensive and difficult to install, although it has saved some properties, including historic cabins run by the US government. .
Fire crews even wrapped the base of the world’s tallest tree this week to protect it from wildfires burning near a famous grove of gigantic ancient sequoias in Sequoia National Park in California. The colossal General Sherman Tree, some of the other giant forest sequoias, a museum, and other buildings have also been shrouded amid the possibility of intense flames.
It comes after another aluminum-wrapped house near Lake Tahoe survived the Caldor fire, about 20 miles west of Diky’s house, while neighboring houses were destroyed.
The wrap keeps heat away from buildings, helping to prevent flammable materials from burning. It also prevents airborne embers – a major contributor to the spread of forest fires – from sliding through vents and other openings in a home. With a fiberglass backing and acrylic adhesive, the envelopes can withstand heat up to 1,022 degrees Fahrenheit (550 Celsius).
Until a decade ago, most of the damage from wildfires was blamed on homes that caught fire as the flames scorched nearby vegetation. Recent studies suggest that a more important role is played by structure-to-structure fires which spread by domino effect due to the enormous heat which causes the explosion of manufactured materials.
The company where Diky bought its packaging gets about 95% of its sales from the US Forest Service and the National Park Service. Firezat Inc. founding president Dan Hirning estimates that the Forest Service has covered 600-700 buildings, bridges, communication towers and other structures in national forests this year alone.
Firefighters on social media compare the wraps to a “big baked potato”. Whoever helped set up some said it felt like ‘wrapping Christmas presents’.
Forest service officials say they have used the envelopes for several years throughout the American West to protect sensitive structures. In Lake Tahoe, they enveloped the Angora Ridge Lookout, a nationally registered historic watchtower, said Phil Heitzke, a battalion commander for the agency.
“Often, Forest Service structures are wrapped up long before the fire,” he said in a statement. Teams can then often concentrate on protecting other buildings or other work.
Firezat sells firewall rolls 5 feet (1.5 meters) wide by 200 feet (61 meters) long for about $ 700 each. Installation by a contractor typically costs thousands of dollars.
“People think we should be selling tons of these things, but it’s not as much as everyone thinks,” Hirning said. Despite the cost, he said a building would not burn unless “fire falls on it”.
A professor of mechanical engineering at Case Western Reserve University in Ohio published 10 years of research on shrouds in the journal Frontiers in Mechanical Engineering in 2019, saying they “have demonstrated both outstanding performance and technical limitations “.
The aluminized surface blocked up to 92 percent of convective heat and up to 96 percent of radiation, Fumiaki Takahashi said.
The packaging is more effective if a forest fire is burning with exposure of less than 10 minutes, he said. This is less effective in areas with high density housing, where the spread of the underworld can burn for hours without being stopped by firefighters.
The envelopes “show promise to be effective, but more research is needed to develop more effective but still lightweight” protection against severe fires, Takahashi said in an email. He said he wouldn’t recommend them to everyone as they require proper installation.
“But once the installation methods were established (like a standard), I would,” he wrote. “There have been several success stories in saving historic cabins by the US Forest Service. “
Hirning said most of the individual buyers he had over the years sought to protect “really expensive cabins, really expensive homes, resorts, etc.” They include owners of $ 5 million lots in Malibu, Calif., Who are asked to sign an agreement that the Forest Service is not responsible for protecting their property in some cases.
A Wyoming rancher once put Hirning on a conference call with a fire commander and an adjuster who would cut his rates if he packed a cabin worth around $ 1.5 million.
“Often these are people who cannot get fire insurance or their insurance has been abandoned. They want to wrap it up to protect their investments that way, ”he said.
Diky suggests getting additional help with setting up the packaging.
“They recommended that three people could do it in 3.5 hours. I brought four contractors with me and worked all day until night… we broke our buttocks for 12.5 hours, ”he said.
Regarding the take-off in sales following the recent wildfires, Hirning said it was “an extremely seasonal business.”
“The first five years, new competitors arrived every year. And at the end of each year, I got a phone call, “Would you be interested in purchasing our inventory?
Once it starts to rain and snow, he says he often doesn’t sell anything for nine months in a row. That could change, however, as climate change contributes to more intense weather conditions and more destructive forest fire seasons, most of the year.