What Are Low-E Glass Windows?

If you think about it, your windows and doors are just big holes in your house. Even though glass or wood covers these holes, hot or cold air can leak in or out of your home – that’s where Low-E glass windows come into play.

Low-E stands for low-emissivity, meaning low amounts of radiant thermal energy are admitted through these windows.

Although it costs more than the average window installation, the benefits will outway the cons down the road.

What’s In Low-E Glass?

By the law of nature, glass is highly emissive to the sun’s heat. Low-E glass is a thin coating of silver and other low emissivity materials to reflect the sun’s heat away from your home.

Low-E Glass Windows Keep Air In

While Low-E glass windows reflect the sun’s heat away, they will also keep warm or cool air in! The thin coating also acts as a shield inside and out to keep your cool air circulating and your warm air toasty depending on the season.

2 Types of Low-E Glass Windows

There are two types of Low-E glass windows:

Passive Low-E coating can actually act as a natural heat source by absorbing as much of the sun’s heat as it can. This type of coating is great for cold winter days with plenty of sun as it can reduce your dependence on artificial heating.
Solar Low-E coating is the exact opposite of passive Low-E as it does its best to reflect the sun’s UV rays. This type of coating would work best in hot climates where you primarily need to keep your house cool for the majority of the year.

Disadvantage of Low-E

Despite their many benefits, Low-E glass windows have their drawbacks.

Once installed, you will notice a significant reduction of natural light in your home. The light reduction may be small, like 25%, but could get as high as 80%. If you like a lot of natural light, have many indoor plants, or both, then Low-E glass windows may not fit your lifestyle.