The most versatile material out there is glass. It can do extraordinary things and is made today more advanced than it was a few years ago! Like Low-e glass, glasses today have the greatest potential to transform your home, and that’s why we use them in our windows.

You may have thought about replacing your windows, but you’re probably wondering what Low-E window glass is. 

So, let’s take a deep dive into the world of Low-E glass, how it works, what types are available, and how it can dramatically improve the energy efficiency of your home. Let’s get started! 

What is Low-E Window Glass?

The “E” in Low-E stands for “emissivity.” When a surface absorbs heat or light energy, such as glass, it reflects off the surface or radiates through it. Emissivity is the ability of a material to release energy. 

But, what does that have to do with windows? If you’ve ever been in a greenhouse, you might know already. Low-E glass is made of two or more sheets of glass that are bonded together, and it creates a barrier between the inside and outside to protect your home from harsh weather and prevent unwanted heat transfer. 

Radiating energy is one of the leading causes of heat transfer in window glass, and Low-E windows radiate less energy, transmitting less heat.

How Low-E Window Glass Works?

Well, the technology is quite simple. Low-E windows are known for their insulating qualities, but they also have a thin coating on the surface of the glass. They might often look tinted, but Low-E glass is not the same as tinted glass.

Tinted glass is made by adding metallic particles, whereas Low-E glasses have microscopic layers of various metallic particles on the surface. These layers turn the glass into something like a filter or a sieve. 

It’s possible to use thin layers of various metals to “filter out” different wavelengths, so by doing that, it’s possible to choose what types of energy get through. 

The Benefits of Low-E Glass

Temperature Regulation

The low-emissivity film of Low-E glass makes your windows warmer during those harsh British Winters. You can keep your home comfortable and enjoy the sense of security that comes with having a well-insulated window.

Ultraviolet (UV) Light Protection

Low-E glass can help filter out infrared radiation. It also limits the amount of ultraviolet radiation allowed to pass through. This feature makes it beneficial for both the health of those who live in the home and the longevity of your furnishings.

The Disadvantages Low-E Glass

Mitigated Natural Light Entry

Low-E glass can sometimes be hard to see through, depending on how you look at it. On the other hand, this could be an advantage because light enters your home more slowly. Or, it could be seen as a disadvantage if you want to go outside and enjoy natural light.

Low-E Glass is Expensive

Low-E glass windows are more expensive than standard toughened glass windows. But, if you’re willing to spend the extra money, depending on how you see it, Low-E windows can be worth it!

Types of Low-E Glass

Low-E glass comprises different metals, including tin, silver, and zinc, all used to create different layers on the surface. These metals are layered in different ways to give the glass various properties. But there are big differences between them.

1. Passive Low-E Coatings (Hard-Coat)

Passive Low-E coatings are designed to maximize the solar heat that passes into a building, creating a “passive” heating effect. It can help reduce the amount of money you have to spend on artificial heating, ideal for colder climates.

2. Solar Control Low-E Coatings (Soft-Coat)

Solar control Low-E windows aim to keep buildings cooler and reduce the amount of energy used by air conditioning. They are ideal for hot climates, and even better if you live in a place with lots of suns!

Climate Considerations for Low-E Glass Windows

Are you looking to upgrade the windows in your home to Low-E windows? Well, you’ll need to consider your climate and what’s most important for you, whether it’s keeping your home cool during the warm summer months or keeping it warm in the cold winter ones. The right combination of windows can do both!

There are still many grey areas where it can be challenging to choose between glass with a passive Low-E coating or solar control Low-E windows. However, having a knowledgeable glass professional help guide you through the selection process ensures you’re sure to select the right window for your home.

Here are some terminologies that manufacturers use to grade Low-E windows:

  • U-Factor values are a measure of how well a window prevents heat from escaping a building. If you want to keep heat in, you should go for windows with lower U-factors.
  • Solar Heat Gain Coefficient (SHGC) measures how well the glass blocks heat from the sun from entering the building. The lower the SHGC, the better and more energy efficient it is for your home.
  • Visible Transmittance (VT) is the measure of how light or dark something is. Low-E Glass with a high visible transmittance allows more light to pass through, while Low-E glass with low visible transmittance has a very dark appearance.

Conclusion: Do You Need Low-E Window Glass?

Are you currently looking for energy-efficient windows? Are you worried that your windows are losing too much heat during the wintertime? If so, then Low-E glass is a must.

By changing how window glass transfers heat, Low-E coatings can help keep homes comfortable while reducing energy costs throughout the year, and it can also prevent your house from getting too hot in the summer.

Editorial Contributors
Matt Greenfield

Matt Greenfield

Matt Greenfield is an experienced writer specializing in home improvement topics. He has a passion for educating and empowering homeowners to make informed decisions about their properties. Matt's writing focuses on a range of topics, including windows, flooring, HVAC, and construction materials. With a background in construction and home renovation, Matt is well-versed in the latest trends and techniques in the industry. His articles offer practical advice and expert insights that help readers tackle their home improvement projects with confidence. Whether you're a DIY enthusiast or a seasoned professional, Matt's writing is sure to provide valuable guidance and inspiration.

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