GIMME SHELTER- Therma-what?: Styrofoam houses explained

Architect Alan Scouten


  Q: I'm thinking about building a house now, and I've heard of this ThermaSteel construction. What exactly is it and what's so great about it? And how do I find a builder? 

A: ThermaSteel is a category of SIPS panel prefabricated construction developed in the 1980s by Radford inventor Luther Dickens, who had already developed the familiar styrofoam molds used to package consumer goods like TVs and computers. One day he discovered that styrofoam actually bonded well to steel with a strong adhesive. Today, this composite technology has evolved into construction panels made of rigid, fire-retardant Modified Expanded Polystyrene Resin bonded to light-weight galvanized steel frames. The panels provide structural framing and insulation all-in-one, and can be used for exterior and interior walls, partitions, floors, and roofs. 

Thousands of ThermaSteel structures have been built around the world, but the technology remains relatively unknown in this county. That's because the vast majority of houses here are still being made of wood, using the stick-built method of construction. As a result, wood has become terribly expensive, more and more scarce, and the quality has deteriorated as well. Now more than ever, panel construction systems seem to be the answer to preserving our natural resources and being kinder to the environment.

SIPS are pre-cut panels filled with polystyrene or polyurethane foam and sandwiched between two layers of strand board, plywood, or fiber-cement. If you want to stay away from wood completely, steel stud frame construction is also an option, but that tends to be very expensive.   

 ThermaSteel is a sort of "bridge" construction between the two, combining the strength of steel with the insulation benefits of styrofoam, but without the wood. ThermaSteel is also extremely lightweight, but its twice as strong as wood frame construction. Unlike SIPS, which can be quite heavy, ThermaSteel panels are easy to work with, and all that's needed to put them together are screws and a screw gun. 

A ThermaSteel house is basically like a styrofoam cooler. When it snows, the snow doesn't melt off the roof because there's so little heat escaping. The house remains cool in the summer because the hot air outside can't find its way in. The electric bill for my own ThermaSteel home, which is 4,000-square-feet, averages just $100 a month. 

If they're willing, any builders can put together a ThermaSteel house. Of course, there's a learning curve on this kind of construction, but I've found that a good builder can pick it up in a matter of hours. 

Read more about ThermaSteel houses in this week's special Home issue!