NAHB Research Center
Windows are no longer simple panes of glass, but have evolved into complex engineered systems. Recent innovations such as double-glazed, gas-filled windows provide greater insulating value and improved energy efficiency, a benefit for windows used in any climate. New and widely used low-emissivity (low-e) coatings may be applied to glass used in double-pane assemblies to control thermal radiation, with the type and placement of the coatings varying according to the climate where the window will be used. Spectrally Selective Glazing incorporates technical advances in low-e coatings that filter out the heat producing portions of the solar spectrum, but still allow the greatest possible visible light transmittance.