There are many things about our homes we overlook on a day-to-day basis, but your windows should not be one of them. Window World has a variety of windows that are Energy Star rated and approved. The U.S. Department of Energy estimates that you could save between $126 to $465 each year by replacing those single-pane windows with Energy Star rated windows. Also, consider windows that hold moisture. Window World has a variety of options that can help with all of the above, including windows, doors and siding.