Window companies in Canada pride themselves on high-quality windows that meet and adhere to the highest standards. This includes Energy Star windows that are known for their durability and energy efficiency. Recently, Energy Star has made some updates in their standards, which directly affects the process of how windows are manufactured here in Canada.

In the following article, we shall outline these changes and how they will affect our products. We are well aware that climate zones and energy star ratings are a component that most customers take into consideration when the time for window replacement comes.

Updates in Energy Star Windows Standards

Since the early 1900s, Energy Star has set the international standard for energy efficient products for consumers and homeowners alike. This, of course, includes Energy Star Canada windows and doors. One of the main benefits of purchasing products bearing the Energy Star label is that they tend to use up to 30% less energy than those that are required by local federal regulations. As they were originally generated in the United States of America, both Canada and the EU (European Union) also use these standards as a guideline for producing building goods and manufacturing consumer products.

Following is a brief description of the standards that are required for windows to be labeled as Energy Star windows:

Visible Transmittance (VT)

VT or Visual Transmittance is a term that refers to the amount of visible light that will pass through the product in question. The value of Visible Transmittance ranges from zero to one hundred. The higher value means that more light is able to be transferred through the said object.


It is related to the R-value in that the R-value measures the insulation value while the U-factor measures the amount of heat transfer. However, neither the U-Factor nor R-Value takes into consideration the amount of heat gain as a result of natural light. A low U-Factor signified a slow transfer of heat to a cold surface from a warm one.

Solar Heat Gain Coefficient (SHGC)

SHGC helps you to calculate the amount of solar radiation that is gained through the window pane. It ranges from zero to one hundred. The lower the SHGCV number is, the less the level of solar heat the window pane transmits will be.

Energy Rating (ER)

The energy rating is the balance between the U-factor and the solar heat gain of a product along with the air-tightness. The Energy Rating ranges from zero to fifty. The lower the energy rating is, the more energy resistant the product is.

*In addition, all windows that are labeled as Energy Star windows are tested to ensure that they meet the proper guidelines for strength, water tightness, and air tightness.

The ability to understand the meaning of the aforementioned values will help consumers determine which style of windows, as well as the material of the window, will be suited best for their homes. In addition, this information is especially useful for those who are considering custom-made windows or other upgrades for their window replacement products. For instance, some homeowners might wish to upgrade to double or triple pane windows with Low-E (Low Emissivity Coatings) or inert gas fills for added energy efficiency.

Windows and Doors companies in Canada are required to label their products to indicate that they are in fact in compliance with Energy Star ratings. Moreover, they will be adopting the new NAFS (North American Fenestration Standards) and will thus label their products accordingly.

If you have any questions as to how the recent changes in Energy Star windows will affect you directly, feel free to contact Atlant Windows. A member of our staff will gladly help explain the new guidelines. Call us today to choose the most energy efficient windows for your home.