What Is Low E-Glass And Why Is It Important?

Posted on: 28 January 2015


If you've been contemplating replacing your existing single pane windows with more energy-efficient models, you probably know that there is more to choosing new windows than just deciding whether you want wood or vinyl frames. The glass you choose is also a vital part of the energy-saving package. Low E-glass offers a number of advantages over standard window glass, but it's important to pick the type of low-E glass that's best suited for your climate and your home.

What is low-e glass?

Low-E glass, sometimes also called lo-E glass, is finished with a low emissivity coating that filters and minimizes the ultraviolet (UV) and infrared rays from the sun without compromising the visible light that passes through the window. This type of glass has a number of benefits. It helps to reduce the energy transfer between the indoors and outdoors. This can result in a 30 to 50 percent reduction in heat loss, according to the U.S. Department of Energy. Low-E glass also helps reduce glare and it helps to keep out UV rays that can fade your carpet, your drapes and your furniture. Keep in mind that low-E glass isn't the same thing as tinted glass. Tinted glass reduces glare and the visible light that enters the window, but has no effect on heat transfer.

Types of low-E glass

Not all low-E glass is created alike. There are three distinct types of low-e glass on the market today.

1. Low-E4 glass -- Low-E4 glass is a good all-purpose glass for both hot and colder climates. In addition to reflecting the sun's rays, the coating on this type of glass also acts as a sound barrier, keeping traffic and other types of noise outdoors where it belongs.

2. Enhanced solar control Low-E glass -- This type of glass is designed for colder climates and actually collects the sun's heat to help heat the home.

3. LoE-366 glass -- This glass blocks up to 95 percent of the sun's UV rays, making it a good choice for homes in hot climates.

Disadvantages of using low-E glass include possible fading to the siding on your home, since this type of glass reflects so much sunlight. This type of glass has also been associated with poor cell phone reception. The reception issue, however, can be overcome by using a distributed antennae system.

While low-E glass may now be the right choice for every home and every homeowner, this type of glass helps reduce heat transfer dramatically, resulting in fewer resources being used and lower energy bills. Talk to your local glass experts, such as Ram Glass Service, for more information.