If you can wrap it, you save it
Homeowner uses aluminum covering to protect his house from wildfire destruction
RENO, Nev. — Martin Diky said he panicked as a huge wildfire started racing down a slope toward his wooden house near Lake Tahoe.
The contractor had enough time to do some quick research and decided to wrap his mountain home with an aluminum protective covering. The material that can withstand intensive heat for short periods resembles tin foil from the kitchen drawer but is modeled after the tent-like shelters that wildland firefighters use as a last resort to protect themselves when trapped by flames.
Diky, who lives most of the time in the San Francisco Bay area, bought $6,000 worth of wrapping from Firezat Inc. in San Diego, enough to cover his 1,400-squarefoot second home on the edge of the small California community of Meyers.
“It’s pretty expensive, and you’d feel stupid if they stopped the fire before it got close,” he said. “But I’m really glad we did it. It was pretty nerve-wracking when the flames came down the slope.”
The flexible aluminum sheets that Diky affixed to his $700,000 home are not widely used because they are pricey and difficult to install, though they have saved some properties, including historic cabins managed by the U.S. government.
Fire crews even wrapped the base of the world’s largest tree this week to protect it from wildfires burning near a famous grove of gigantic old-growth sequoias in California’s Sequoia National Park. The colossal General Sherman Tree, some of the other sequoias in the Giant Forest, a museum and some other buildings also were wrapped amid the possibility of intense flames.
It comes after another aluminum-wrapped home near Lake Tahoe survived the Caldor Fire, about 20 miles west of Diky’s home, while neighboring houses were destroyed.
The wrapping deflects heat away from buildings, helping prevent flammable materials from combusting. It also keeps airborne embers — a major contributor to spreading wildfires — from slipping through vents and other openings in a home. With a fiberglass backing and acrylic adhesive, the wraps can withstand heat of up to 1,022 degrees.
The company where Diky bought his wraps gets about 95% of its sales from the U.S. Forest Service and National Park Service. Firezat Inc. founding president Dan Hirning estimates the Forest Service has wrapped 600 to 700 buildings, bridges, communication towers and other structures in national forests this year alone.
Firezat sells fire shield rolls that are 5 feet wide by 200 feet long for about $700 each. Installation by a contractor typically costs thousands of dollars.
A mechanical engineering professor at Ohio’s Case Western Reserve University published 10 years of research about protective wraps in the Frontiers in Mechanical Engineering journal in 2019, saying they “demonstrated both remarkable performance and technical limitations.”
The aluminized surface blocked up to 92% of convective heat and up to 96% of radiation, Fumiaki Takahashi said.
The wrapping is most effective if a wildfire burns past with exposure of less than 10 minutes, he said. It’s less effective in areas with high-density housing, where spreading infernos can burn for hours without being stopped by firefighters.