Insulating Concrete Forms
This is a 60-year-old technology that's enjoying new life with the discovery of its energy-saving properties.
The Portland Cement Association, one of the top makers of concrete forms, defines them as "cast-in-place concrete walls that are sandwiched between two layers of insulation material." Concrete is poured into forms that serve as insulation layers and remain in place as a permanent part of the structure. The technology is used in freestanding walls and building blocks.
An industry-funded study by the Massachusetts Institute of Technology issued a report in late 2010 that said buildings made from insulated concrete forms saved 20 percent over the energy consumed by wood-frame buildings in cold climates such as Chicago [source: Ochsendorf].