Choosing an Energy-Efficient Window
Observe the Low-E rating - This is a coating on the glass that is rated for its ability to reflect UV rays. They are slightly tinted and apple to different areas of the glass depending on the region. In warmer climates, the coating appears on the outside panes, and in colder climates, it’s used on the inside pane.
Window styles make a difference - Both awning and casement windows have the best energy efficiency because they close tightly within their weather stripping when compared to single- and double-hung windows and slider windows.
Look for multi-paned windows - Energy efficiency greatly improves with at least a double-paned window, in addition to panes of glass being separated by krypton or argon gas and warm edge spacers.
Invest in weather stripping - Weather stripping makes all the difference when it comes to enhancing the energy efficiency of your windows — it keeps the elements like rain and cold air out, while keeping the indoor temperature ambient.
Review the U-factors - When you’re looking at the U-factor on windows, look for those with low U-values — they have the best insulating properties, thus improved energy efficiency.