Our Tips to Choose the Best Energy-Efficient Windows

It’s a well-known fact that windows are more than a vital part of a home. During the day, they allow natural sunlight to seep in, and in summer, they allow for a nice, occasional breeze of fresh air.

Wind coming in through open windows is a good thing, however, if it’s still the case when the windows are closed, well then, that’s a problem! The opposite is also true, especially in winter when our main goal is to keep our house warm. We want to keep the heat inside, not let it get out. 

Fortunately, different types of highly energy-efficient windows will help you save money on your heating bills by controlling air drafts and maintaining an ambient temperature in your house.

What’s the best type of window for a renovation or construction project?

Choosing the best type of window depends on several factors, such as the home’s architectural design, your preferred aesthetics, weather patterns in your region, your budget, and your needs in terms of energy efficiency, soundproofing, safety, etc.

Choosing Energy-Efficient Windows for Your Home

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If the time has come to change your windows, consider the energy efficiency of the ones you’re looking to install (or have installed). However, before changing all the windows in your house, you can also ensure that such a move is necessary. Changing your windows just for the heck of it isn’t always a win-win solution. And, getting stuck with your old windows that aren’t really problematic isn’t always an eco-friendly choice. 

However, if you’re planning a renovation project, you may want to take the opportunity to renew your windows. Landing on energy-efficient windows does have its advantages. For example, the Rénoclimat financial assistance program may be of help, financially speaking. Be on the lookout for the current financial aid programs available.

When it comes to your old windows, you can check out the Recyc-Québec (French only) website to find out the right way to dispose of them, based on the region in which you reside. 

Window ER Score

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There are many ways to evaluate a window’s energy rating. Typically speaking, energy-efficient products are evaluated to then be given an ER score (energy rating). The Canadian Standards Association (CSA Group) is mandated with determining the rating calculation method, which determines:

• Heat gain inside the home resulting from the sun;

• Thermal losses, whether it be from the frame, the spacer (the material used to create a space between the glass and the window) or the glass itself;

• And lastly, heat loss that stems from drafts.

This ER score, which is a weighted measure, includes the previously mentioned factors, and produces a result that’s calculated on a scale of 0 to 50—the higher the score, the better the efficiency levels.

What windows are the most energy-efficient?

The windows with the best insulation properties are those with double panes, a casement seal, and decent profiles. A double-paned window is made of two separate glass panes separated by a void filled with inert gas (typically argon). This type of window glazing is the best option when it comes to thermal insulation and soundproofing and allows for significantly less heat loss. 

In terms of materials, PVC, wood, and aluminum are the most commonly used window materials. Windows with a PVC frame have good thermal insulation and great soundproofing. Wood models also provide good insulation, however, they require a lot more maintenance and are most expensive. Aluminum windows are durable and resistant but provide little insulation. 

Energy Star Windows

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Amongst the most sought-after models, there are the Energy Star-certified models. These window models include double (or triple) glass panes that allow for very little heat loss and are filled with inert gas, such as argon or krypton. Argon—less expensive than krypton but slightly less efficient—allows for reduced heat loss when inserted between window panes since it’s a better insulator than air.

By comparison, traditional windows are filled with air and only have double panes, with standard-quality glass. 

Different types of Energy Star-certified windows are grouped into categories based on the climatic zones inhabited. This means that in addition to choosing products with the best energy efficiency ratings, one must also make sure that the windows chosen are suited for the weather conditions where one resides. Otherwise, even installing an Energy Star-certified window, no matter how good the ER score is, is useless. Note that Canada is split into four (4) climatic zones, depending on the average yearly temperature. 

Beware! Some products don’t necessarily have the official seal but still meet CSA standards.

For more information, here are a few pertinent websites: 

• CAA Québec - Energy Efficiency Criteria

• La Presse - Des fenêtres à haut rendement énergétique (French only)

• Natural Resources Canada - Energy Efficiency Ratings: Search

Looking for more information about windows and doors? Check out our Renovation Guide: Door and Window.