Research hub
A window's rated performance is produced almost entirely by the insulating glass unit. These references explain the components behind the numbers on an NFRC label.
U-factor and SHGC are produced almost entirely by the glass package: the low-E coating, the gas fill, and the spacer. This page explains what each component does and how to read an NFRC label.
Reviewed by Technical Review Board
Share your project details and we will introduce you to independently licensed window replacement contractors serving your Orange County city. There is no cost and no obligation.
We are not a contractor. We do not perform construction services, quote projects, or hold contractor licenses.