What higher energy performance means for your home.
Higher efficiency, lower energy bills.
Windows, doors and skylights may appear passive, but they’re always performing. High-performance products regulate the flow of heat and light that comes in and out of your home, keeping your electricity costs low.
Natural light that doesn’t add heat.
Certain products use spectrally selective glass that blocks infrared light while still allowing high levels of visible light—so you can daylight your home while maintaining comfortable temperatures.
Constant temperatures, and consistent comfort.
In winter, poorly performing windows, doors and skylights can create drafts by cycling air at different temperatures through your home. In summer, they can make heating and cooling more difficult by allowing the sun to influence the temperature in the room. High-performing products help to keep temperatures consistent year-round, so your home stays comfortable no matter the conditions.
No more faded fabrics.
UV radiation is responsible for 40-60% of fading in fabrics, and it passes through glass whether it’s sunny or cloudy outside. High-performing products can reflect up to 74% of the damage caused by UV rays, and protective films can block up to 99%, keeping your furniture looking like new.
Insulation built for all seasons.
When it comes to insulating your home against heat and cold, a poor-performing product is like a hole in the wall. Solar control window film applied to the interior of your windows is a transparent “solar shield” that can reject up to 80% of the sun’s heat, keeping your home cooler and more comfortable in the summer, and well-heated in the winter.
How windows are built, and how it impacts your purchase.
Knowing the basic structure of a window and how its internal parts affect efficiency can help you make smarter purchase decisions. These basic terms and concepts will help you get started.
Glazing system: Layers of glass filled with a gas or combination of gasses and sealed into place, creating insulation inside of a window. Doors with glass panes also contain glazing systems.
Windows are often described by the number of glazings (or glass layers) they contain:
Single-glazed = One pane of glass
Double-glazed = Two panes of glass
Triple-glazed = Three panes of glass
Quad-glazed = Four panes of glass
Generally, the more glazings, the better insulation a product offers.
Spacer: A component that separates and maintains space between glazings. Spacers may be made of metal or non-metal materials, or both. Because they’re located within the window’s structure, spacers can affect a window’s performance based on how much heat their material lets through.
Frame: The enclosing structure of a window, door, or skylight. The choice of frame material for your window can depend on many factors—like style preference, cost, building needs, and upkeep. Material choice can also affect the window’s overall performance, as some material may have benefits in one area at the expense of lower performance in other areas. Use the NFRC label to determine specific energy performance characteristics of window products before you buy.
Narrow your search with the NFRC Certified Product Directory.
Ready to start searching for your perfect window, door, or skylight? Give yourself a great starting point by searching our database of NFRC-certified products.