Whenever you hear about ways to go green, save on utilities, or increase interior climate comfort, windows are at the top of the list of things to change.
People with older homes may blame single-pane windows for drafts and increased energy bills. People with newer homes may wish for better window design or for more expensive windows instead of builder-grade, double-pane vinyl windows.
So what actually makes a window energy efficient? How do these windows work? Here is what you need to know about how window design actually affects your home.
Multiple Panes of Glass
The first innovation in windows was moving from a single-pane to a double-pane design. Early double-pane windows did not have any other additional features. They simply had the benefit of another barrier between the inside and outside environments, with a buffer of air in between.
The benefits of this design from a comfort standpoint were immediately evident. Feeling chilled while sitting next to the window or feeling a draft from the window was much less common after implementing a double-pane design for home windows. Triple-pane windows would predictably offer even more insulation, especially against noise pollution as well as heat gain and loss.
However, the presence of two (or more) panes does not, in and of itself, an energy-efficient window make. The addition of more design features are what make the most difference for an energy-efficient window.
Newer Features in Window and Glass Design
A number of features, especially when combined, work together to make your windows as effective as possible when it comes to energy conservation. These features include the following.
One of the problems with glass is that it conducts heat and light very easily. Of course, glass has no equal when it comes to a window’s beauty. So, in order to make glass a more superior material for conducting light without the loss of heat, window manufacturers now place several layers of low-emission coatings on window glass.
The coatings help to curb the transmission of UV rays through the window, offering a number of advantages.
First, you won’t experience the amount of heat gain from a window because UV light is one of the main reasons why a room might increase in temperature due to bright sun. Have you ever felt like it was 10 degrees hotter in the summer just because you’re by the window? Tints and films help to reduce that warming effect.
You also won’t have fading or damage to upholstery or your own skin from sitting in the light of the window. Wallpaper and carpets can also fade if your windows do not have a low-E coating. These coatings can be clear, tinted, or even reflective depending on what purpose you want your window to serve.
Sometimes, low-E films can be applied to existing glass. If you have old windows but replacement is not a financially feasible option, it’s something to consider.
Gas Fillings Between Panes
Another innovation is further increasing a windows insulation. When two-pane windows were first developed, normal air filled the space between frames. However, not all gases act the same, and some are much more insulating than others.
Energy-efficient windows are now filled with a nonreactive element gas (usually argon). This gas is what is known as a noble gas. It does not easily make compounds with other elements, nor will it break up into less stable bonds. Because the gas is so stable, it’s a terrible conductor for heat. Windows with argon will assist in maintaining a desirable interior temperature.
Finally, newer, energy-efficient windows will not use metal for spacers. The window sashes and the space between panes around the frame are filled with a dense foam that helps to prevent any loss of air through any part of the window.
These spacers can be the difference between a cheap window and an energy-efficient window. In addition, they’ll help you save money on heating and cooling your home.
Hidden Savings for Homeowners
Finally, it’s worth it to recognize that savings might not just come from reduced energy due to better glass and window design. When you put in new glass or entirely new window units, you may have the chance to add safety features.
For example, if your window is made from storm-resistant glass (so it does not shatter), you could see reduced home insurance costs. Other security features from newer windows can also help you score points with your insurer.
Warranties on glass and window films can also make future repairs much simpler and less expensive.