Low-E glasses are becoming increasingly popular among homeowners day by day. One of its most well-known benefits is that it is energy-efficient. So, you might wonder, how does low-E glass save energy?

The insulating and reflecting mechanism of Low-E glasses makes them energy-efficient. These glasses reflect heat. As a result, the heat stays out on hot days. Besides, it keeps the home warm during winter.

There are many benefits of Low-E glasses. In this article, I'll go a bit deeper into how they work and also the advantages of these glasses that make them so popular among homeowners. So, without further ado, let’s get right into it.

What Does Low-E Glass Mean?

The complete form of Low-E glass is Low-emittance glass. It is a type of glass with a metallic or metal oxide covering that is so thin it is almost invisible.

The "E" in Low-E refers to emissivity. Therefore knowing this can help you comprehend the characteristics of Low-E glass. Emissivity is scaled between 0 and 1, with 0 representing a reflective mirror and 1 representing an utterly blacked-out surface.

A material's emissivity is how well it radiates and transmits heat. So, low E glass will dissipate lower heat energy.

Well, you might have seen heat leaking via a window's surface if you've got close to one with a typical pane of glass. Radiant heat is a sort of thermal energy that all objects eventually release.

Like plastic and wood, glasses are natural insulators, making them effective heat absorbers. It takes in the sun's thermal energy or your home's internal heating. And then gently emits into the area around the glass.

However, after the heat release, it either results in undesired thermal loss during the winter or unwelcome solar heat gain during the summer. And manufacturers design low emissivity to reduce the amount of "undesirable" heat energy.

So, they create low-E glass coatings to lessen the impacts of thermal transference via the glass. Furthermore, it reduces other harmful consequences of the sunlight, like ultraviolet (UV) rays.

Again, these coatings are too thin, enabling the substance to reflect that radiant energy. The Low-E layer has two functions. Either it keeps valuable heat inside the house during the winter by retaining heat from escaping through the glass. Or it blocks heat on a hot summer day.

How Does Low-E Glass Work?

The addition of microscopic reflective coating layers to low E glass makes it function. These coatings filter out all the bulk of light's IR wavelengths and UV rays while allowing necessary light via the window.

Buildings with Low-E insulated glass provide higher thermal insulation. The sun or the building's HVAC system's heat won't get transferred via the glass to the outside. Instead, it will return inside, bouncing off the low-E glass. Due to the skinny layers of metallic coating layers on the glass, it can complete this procedure.

Low-E coatings for glass surfaces have the function of converting the radiation. It allows the beneficial rays to flow through while neutralizing the detrimental ones. Low emissivity refers to a surface's relative capacity to radiate heat. Low-E glass windows assist a room collecting and holding onto heat while reducing UV rays by 99.9%.

In contrast to tinted glass, the low-E glass acts as a filter for specific energy wavelengths. It lets light through while retaining heat. Tinted windows block both the light's short and long wavelengths. However, low-E coating glass allows short wavelengths of light while blocking the latter (heat).

Benefits of Low-E Glass

Low-E Glass is a lot more energy-efficient than regular glass. Besides, it is insulative, durable, and protects the building from UV rays.

There are tons of benefits of Low-E glass. The following are some of the most outstanding advantages of this type of glass:

UV Protection

Low E glass can keep the great bulk of UV rays from entering the house. Ultraviolet light has the annoying tendency to maintain a bleaching impact on the carpets and fixtures, fading their color.

Low E glazing has a coating that can block these particular radiation wavelengths successfully. So, Low-E glass safeguards both your family and your furnishings.

Insulating Power

One of the Low-E glass's most outstanding benefits is the incredible insulation power it gives your windows.

Because of its low-emissivity layer, low-E glass is more insulative than ordinary uncoated glass. Thus, it can keep the occupants of your home a little warmer during the chilly winter days.

Lowers Energy Costs

Low-E glass may help reduce some energy loss, which occurs via non-coated doors and windows. Generally, these glasses can reduce around 10-50% energy loss in a home.

Thus, homeowners can save money on heating and cooling expenses. Low-E windows have thermal and insulative qualities as they have a thin coating. So, it can assist in lowering energy expenses related to heat transmission via windows.

Safe & Non-toxic

The coating on the Low-E glasses is entirely safe and non-toxic. So, you won't have to stress over hazardous chemicals or adverse effects on yourself, your family, or even your pets.

Cost-Effective & Durable

The Low-E coating is thick and precisely put across the whole glass surface. So, it is unlikely to scratch or otherwise sustain damage. These are generally more durable than regular glasses and lasts for a long time, even in areas with extreme weather conditions.

Moreover, Low-E glass windows are often only a few dollars more expensive than standard glass windows. And energy savings typically offset the additional expense.

Why Install Energy Efficient Low-E Glass in Your Home?

You can decrease heat loss via windows by installing Low-E glass in your home. As a result, you can improve the comfort of your house and lower your energy costs.

Low-E and tinted windows exclude UV and infrared radiation. However, tinted windows can block a significant amount of natural sunlight. On the other hand, as the coating is almost colorless, Low-E windows let plenty of light enter your home. That too without discoloring your furnishings!

Additionally, tinted glass absorbs sunlight. Therefore, it becomes hot. And any insulating qualities the window might otherwise possess could be compromised by this. It would raise your energy expenditure. But, due to the coating, low-E windows are far more insulative than regular non-coated windows.


Low-E glasses are worth it if you consider their long-time benefits. By now, you've got to know the answer to your question, "How does Low-E glass save energy?" So, install them in your home and reduce your energy bills! Thanks for reading through.

Hopefully, you've found this article helpful. Best wishes!

September 13, 2022 — Della Wang