The Science Behind Energy Efficient Windows

IGU’s have made two major technological improvements.  The first is a microscopically thin, low emissivity layer in the window which is commonly known as Low-E.  This clear coating—Low-E—is specifically engineered to block heat. When the sun’s UV rays enter a home, the Low-E clear coating optimizes light transmission and keeps the heat discomfort of UV rays from penetrating the home.  The Low-E coating is like applying a layer of shade and sunblock without significantly changing the look of the window.

The second technology improvement is filling the space between the panes with an inert gas called Aragon. Aragon is denser than air and adds to the thermal efficiency of the window.  It also helps keep the temperature of the glass much closer to the temperature inside, thus lowering the energy load requirement of the home.

Upgraded insulated glass units can drastically improve your home’s ambient temperature. For example: if you take a normal sized house on an 89°F day, Low-E can reduce the heat gain, at it’s hottest time, around 1,400 BTU’s an hour.

Unfortunately if your windows are over 15 years old there is a good chance that these technology features are not present.  However if you have those first generation vinyl frames and others, we can often replace just the IGU’s saving you thousands. Along with the cost savings the thermal efficacy will be improved and your home will be much more comfortable! Washington Energy Services can get new IGU’s in quickly if your current windows are in a vinyl, wood or fiberglass frame and at least ¼” thick.

If you have a few older double pane windows that get a lot of exposure to the sun, you can often replace just the glass for a fraction of the cost. In fact, if you give us a call at 800-398-4663 we can provide you pricing over the phone for new IGU’s in most cases.