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A drive for energy-efficient building supplies reveals an unlikely option.
Published Aug. 7, 2007

Turning foam into building blocks

- Stack hollow, interlocking foam blocks atop steel reinforcing bars protruding from the home's concrete foundation.

- Secure the foam wall with braces and inject wet concrete into gaps in the blocks.

- The resulting solid concrete wall has a foam skin that serves as insulation and a sound buffer.

How's this for a tough sell in hurricane-prone Florida: Build your homes and offices out of a material a few degrees removed from packaging peanuts.

"I hear it all the time: Why would I build my house out of Styrofoam or coffee cups?" said Gray Rideout of Carroll's Building Materials, a $9-million-a-year St. Petersburg concrete and masonry supply company.

But the push for energy-efficient construction, part of the green campaign advocated by Gov. Charlie Crist, is prompting a second look at foam. The two-decades-old technology consists of raising walls from hollow, interlocking foam blocks, ribbing them with steel bars and pouring concrete into the gaps.

The resulting solid wall comes with extra inches of insulation efficient at fending off Florida heat and dampness. Flimsiness isn't a problem, either. Proponents insist foam construction withstands the fury of all but the strongest storms.

"It basically makes a building like a vault," said Dave Piggot of First Florida Contracting Services in Clearwater.

Two years ago, Piggot's company delivered a foam building to house Happy Feet Plus, a Birkenstock shoe store on U.S. 19. Combined with a heat-deflecting roof, Happy Feet saves an estimated 40 percent on its air conditioning bill.

Rideout's company is the Florida "master distributor'' for the BuildBlock brand of insulated concrete forms, or ICFs. The blocks are made from plastic pellets in heat-treated molds by Speedling Inc. in Sun City.

When it comes to the overall construction industry, foam fabrication scarcely rates a mention as a niche player. For starters, using foam blocks costs about 5 percent more than using standard concrete block (but it could pay for itself in a few years of energy savings). That surcharge, combined with the foam-is-flimsy misconceptions, is enough to scare off large builders.

Carroll's has supplied the blocks to three Habitat for Humanity homes in Pinellas County. The blocks' ease of lifting was the selling point for the projects, dependent as they are on volunteer labor.

Commercial applications are expected to grow. A Fort Myers contractor already tested the limits of the material by successfully erecting 11-story twin towers with foam blocks. Big-shot St. Petersburg developer Grady Pridgen has inquired about enlisting such green building methods in his projects.

"It's not just for the hippy-dippy tie-died crowd," Rideout said. In fact, some green purists take foam to task. The reason? It's made of petroleum. Recent oil price increases pushed up the cost of the blocks about 25 percent.

Nevertheless, with energy efficiency becoming gospel in Tallahassee, expect the unconventional to become increasingly conventional.

Said Piggot: "This isn't going away. In the future there will be more green buildings in Pinellas."