Windows are one of the most high-tech products in residential construction. Since the early 1980s, the energy performance of typical windows has increased by more than 50 percent, the result of both improvements in glazing and in frame construction.

The National Fenestration Rating Council (NFRC) publishes the energy performance of certified window products, and in some states manufacturers are required to label their windows with the NFRC’s rating. These ratings are like the EPA mileage rating for cars—they may not provide actual energy consumption in a particular application, but are useful for comparison.


Products in Windows

4M Sunscreens
Quanta Technologies, Inc.
American Bird Conservancy
Allied Window, Inc.
Alpen Fiberglass Windows
Alpen High Performance Products, LLC
Alutech United, Inc.
Madico Window Films
Better Than Ever Window Preservation
Bieber Architectural Windows
Hunter Douglas Contract
Casagrande Woodworks
Cascadia Windows and Doors
Mathews Brothers


Aug 14, 2009 5:18 PM ET

double hung windows
by phil

I'm looking for window infiltration rates on the most popular windows