Retrofitting Exterior Foam on Existing Walls

Achieving necessary reductions in greenhouse gas emissions will require almost every home in colder climates of the U.S. to undergo a deep-energy retrofit, often increasing wall insulation to R-30 or more and attic insulation to R-50. Although these retrofits are not technically challenging, they are extraordinarily expensive, running $50,000–$100,000 per house (see EBN July 2007). A new product from Quad-Lock Building Systems, a Canadian manufacturer of insulated concrete forms (ICFs), can simplify the installation of exterior foam on existing houses. The R-etro System includes four components: 4¼"-thick (110 mm) panels (called Plus Panels), plastic clips (called R-etro Ties), galvanized steel starting track, and fasteners.