ICF (Insulating Concrete Form): A relatively new building material comprised of lightweight, interlocking "building blocks" that double as concrete forms. ICFs are reinforced with rebar and filled with concrete. They remain in place as interior and exterior insulation. The end result is a highly energy efficient, sound insulating, fire resistant building system that reduces wood use and the destruction of forests. To learn more about this construction method, visit www.forms.org.

ICF include the following brand products:

Arxx Building Products
www.arxxbuild.com

Nudura Corporation
www.nudura.com

Quad-Lock Building Systems Ltd.
www.quadlock.com

ECO-Block
www.eco-block.com