So when you are shopping for new windows for your home look for that NFRC label. If a window does not display a label, or has a number that is a little high, you may want to rethink your choice. The SHGC rating is an important part of a replacement window and it’s worth checking...
(For example, the WASCO double hung tests as 0.03 and still receives a value of 0.1, and the tilt and turn tests at LESS than 0.01 in structural tests, and would receive a rating of 0.1 from the NFRC! AAMA records to 0.01) Does air leakage have a large influence on energy bills...