Triple-Glazed** with Low-Solar-Gain Low-E* Glass, Argon/Krypton Gas

This figure illustrates the performance of a window with a very low heat loss rate (low U-factor). In this case there are three glazing layers and two Low-E coatings, 1/2" argon gas or 1/4" krypton gas fill between glazings, and low-conductance edge spacers. The middle glazing layer can be glass or plastic film. Some windows use four glazing layers (two glass layers and two suspended plastic films). Both Low-E coatings in this product have high visible light transmittance. The use of three layers, however, reduces the beneficial solar heat gain. This product is suited for buildings located in very cold climates, although Double-Glazed with High Solar Gain Low-E should be considered if passive solar heat gain is desired.

*Spectrally Selective
**Includes Double Glazing with Suspended Film

Note: These values are for the center of glass only. They should only be used to compare the effect of different glazing types, not to compare total window products. Frame choice can drastically affect performance.