clock menu more-arrow no yes mobile

How to Build a Fireproof Home Using ICF Blocks

Insulated concrete forms—combined with flame-resistant roofing and siding—make for one safe house.

A new home being made out of ICF blocks. iStock

The first “Fortified...for Safer Living” house was completed in Florida in 2005 and built with an insulated concrete form ECO-Block wall system. A program of the Institute for Business and Home Safety, “Fortified...for Safer Living” specifies construction, design, and landscaping guidelines to increase a new home’s resistance to natural disasters such as hurricanes, flooding, and wildfires.

As thousands of Southern Californians contemplate how they’ll rebuild their homes charred by the wildfires ripping through the region, they’ll undoubtedly look for materials that won’t burn.

What are Insulated Concrete Forms (ICFs)?

The answer for many of individuals in areas at risk of wildfires will be ICFs (insulated concrete forms)—polystyrene blocks that fit together like Legos to form a house's shell. Filled with concrete—one of the most fire-and-heat-resistant construction materials—ICFs create solid insulated walls that block out sound and weather. They can reportedly withstand a fire for up to four hours.

While ICFs have been around for decades, their use has mostly been limited to commercial and institutional buildings, such as hotels and schools. But nationwide training camps sponsored by the United Brotherhood of Carpenters and Joiners of America now teach carpenters to build houses out of the stuff.

How to Use Insulated Concrete Forms

Using ICFs costs 1 to 4 percent more than what you would pay for a bare-bones wood-frame house with no built-in fire protection, says Vera Novak, Technical Services Manager for the Insulating Concrete Form Association. The material can save money in the long run because it helps prevent heated and cooled air from escaping through the walls; it's a primary building block in many Energy Star-rated homes.

ICFs mean little, however, without flame-resistant roofing and siding. "You can't just put on a regular wood roof and expect the wildfires to go around you," Novak says. "You must make sure that your roofing choices are equally fire resistant. That can be done with metal, concrete, and various types of tiles." Safe bets for siding are stucco, stone, and brick.


For more information on ICFs, check the Insulating Concrete Form Association's website or call 888-864-4232.