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LoE Glass — What is it? How Does it Work?

Low Emissivity (LoE) Coatings are an important factor in the energy performance of your windows and doors. These coatings have been developed to increase the energy efficiency of your windows by reducing the emissivity of one or more of the glass surfaces.

How LoE Works

LoE is a thin, nearly colorless metallic coating that allows most natural light to enter freely through the window but absorbs a significant portion of short-wave heat energy.

In the summer, long-wave heat energy radiating from the sun is reflected back outside, helping to keep the interior of your home cool. In winter, internal long-wave heat energy is reflected back inside, keeping your home warm and lowering heating costs.

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Types of LoE Coatings

There are two basic types of LoE coatings for windows and doors: soft coat and hard coat.

Soft Coat LoE, or sputter coating, is applied in multiple layers in a vacuum chamber and provides the highest level of performance and a nearly invisible coating. Soft coat offers optimum winter u-factors, and up to 70% less UV transmission compared with standard clear glazing.

Hard Coat, or pyrolitic coating, is a coating that is sprayed onto the glass surface at a high temperature. This coating is relatively durable, and can be tempered for increased safety after the coating application. While it has higher u-values, resulting in reduced thermal performance compared to soft coat LoE, it has a higher SHGC (Solar Heat Gain Coefficient), which may be desirable in some applications.

For information on Low Emissivity Glass and other glass options we offer, visit our “Glass Options” page. 

Every EuroLine product comes standard with a soft coat LoE and the space between the panes is filled with argon gas, which offers even greater thermal performance.

Visit our products pages for information about our windows, doors, options and accessories to help you choose the most energy efficient products for your particular needs.

For more information about LoE and gas fills, visit Efficient Windows.

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