5 reasons to choose Energy Star windows

Energy Star windows have grabbed the majority of market share for replacement windows since the program began in 1998. Since that time more than 270 million windows have been replaced across the U.S. the organization says. There are five factors that make up this now-coveted rating:

1. Improved frame designs
2. Multiple panes
3. Low-e glass
4. Glass fills
5. Warm edge spacers

Deciding which window options work best for your renovation project can be a daunting task, especially since the Energy Star seal carries with it a 15-percent or more cost premium over standard windows.

How to choose Energy Star windows

• Multiple panes: The simplest way to reduce energy loss through windows. Double and triple pane windows insulate the interior pane from outside temperatures. Triple pane windows cost between 10 and 25 percent more and have a thicker profile than other windows.


• Low-E glass: Low-emissive glass uses an invisible, metallic coating to reflect radiant heat back into your home. This is one of the more cost-effective options of Energy Star windows.


• Glass fills: Inert gasses such as argon or krypton further reduce heat loss through window panes. Hard costs are hard to estimate and vary by window size, type of gas fill used, window location and climate.


• Warm-edge spacers: Window panes must be kept a certain distance apart for insulation purposes. Aluminum spacers are commonplace, but they also conduct heat and cold. Stainless steel, thermoplastic and insulated spacers reduce this effect.


• Improved frame designs: By splitting the exterior and interior frame pieces, window manufacturers create a thermal break and increase the window's insulating value. The Efficient Windows Collaborative says its more important in hot climates to use a better glazing system, than windows that incorporate a thermal break.

Benefits of the Energy Star brand

The primary benefit of Energy Star windows is that they keep the interior pane of glass warmer in the winter and eliminate cold zones in the home. In the summer, the windows deflect sunlight and reduce uncomfortable heat gain associated with poorer-quality windows.

Windows can account for nearly a quarter of total household energy use, the Department of Energy says. Although top-of-the-line Energy Star windows can significantly reduce energy consumption costs, these windows are much more expensive. Discuss which options are best for you with qualified window salesperson.