Non-Traditional Structural Materials Are Gaining Favor Among Forward-Thinking BuildersConsider the Alternatives

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Still, ICFs' 5 percent to 10 percent materials-only price premium over CMUs and poured concrete, not considering the labor savings of having integral insulation and permanent forms, is a tough nut to crack with price-sensitive builders. ICFs also suffer from regional building cultures that are married to stick framing and slabs and from a shortage of trained installers to meet demand.

To address the latter issue, the ICF industry is working with the NAHB and its Home Builders Institute educational arm, as well as the United Brother­hood of Carpenters union, to "transition them from stick-framing to ICFs and concrete," Niehoff says. Owens Corning, meanwhile, announced a training and certification program for its ICF system last year.

As for distribution, the ICF industry seems typically fragmented for a relatively young industry. While some manufacturers are actively initiating direct sales relationships with builders to help keep prices competitive, others are willing to suffer supply channel markups of up to three times the cost of a block to enable local support for the technology.

Structural insulated panels
Structural insulated panels sandwich a thick foam panel between two layers of OSB to create structural wall and roof sections. The resulting panel is ready to finish on both faces. It also creates a thermally superior and more reliable envelope to a stick-framed house; a

4-inch SIP wall is 36 percent more thermally efficient than an insulated 2x4 wall, according to the Oak Ridge National Laboratory.

According to NAHB research, SIPs were used as the structural wall material for 1.7 percent of all new, single-family homes built in 2005, a full percentage point higher than five years earlier and now representing nearly 30,000 new homes annually.

Because SIPs are a wood-based system, they are more familiar to framers than a concrete alternative. SIPs are easily manipulated on site with common construction tools, are compatible with other wood framing materials and practices, and offer greater design flexibility and mainstream marketability.

As full wall panels, they often assemble even faster than ICFs, and require no pour or cure time. Those savings help balance a 15 percent or more materials-only price difference between SIPs and stick framing, one of several hurdles the industry faces.

SIPs' installed cost savings, and the system's energy-saving benefits, are what drove Ferrier to the technology. "SIPs give me the biggest bang for my energy-efficient buck," he says.

SIPs walls were adopted into the International Residential Code (IRC) last May, though they may still be hindered at the local level. The language in the IRC was based on a prescriptive method for SIP wall construction developed by the Partnership for Advancing Technology in Housing. The standardized method for calculating and using SIPs enables builders to gain code approval without the stamp of a licensed architect or engineer and puts the technology on par, code-wise, with ICFs and steel framing in residential construction.