Energy efficiency is important to many window buyers – but when it comes time to select a window, nearly every window is manufactured to offer excellent energy efficiency to varying degrees, usually based on cost. While each manufacturer has specific energy-efficient features that they offer, most of the windows on the market today are energy efficient. So how do you choose the right window for maximum energy efficiency within your cost range? The answer is simple – buy what you can afford for your specific situation, and ensure that it is installed correctly.
Installation – the number one ingredient in energy efficiency
If your window is installed improperly, you will be throwing most of the energy-efficient features you paid for out the window – or more specifically out around the frame. Proper levelling and ensuring that the area around the window is sealed and insulated is essential to getting the performance out of the windows that you’ve paid for. Professional installation is the best insurance that your new windows will work out the way you want them to, and the cost is less than you would expect. Even if you haven’t purchased your windows from us, call us for a quote if you want them to be professionally installed. Additionally, if you’ve purchased a new home with newly installed windows and aren’t sure if they’re installed properly, we’ll come out and have a look and give you a quote if we see issues that need to be fixed.
Window glass and construction for energy efficiency
Glazing makes a huge difference in the performance of your windows, but a triple glaze can give you too much weight on the window, which can be a strain on the frame. This can be an issue with windows that you plan on opening and closing in your home. A low-e coating can help to bring the energy efficiency performance of a double-glazed window up to that of a triple-glazed window. What we recommend for the best performance in the North Bay area is a double-glazed window with a low-e 270/I89 coating.
Triple glazing is good for patio doors, or windows that don’t operate. If you are opening or sliding it often, the weight on the frame can lead to wear and tear on the frame. The most extreme energy efficient window is a heavy, triple-glazed window with the maximum amount of weather stripping.
If you do go with triple glazed windows, make sure they have a ½” air space filled with argon gas. Some companies advertise a triple glaze, but only with a ¼” air space, which doesn’t give you true triple performance. That insulated airspace is absolutely necessary, especially if you have a low-e coating. Low-e coatings are designed to reflect, and contain metal. This reflects sun back on the outside or your heat on the inside. None of these coatings can stop thermal transfer – only air space can do that. Argon gas is ten times heavier than dead air, providing an extra barrier for thermal transfer.
What does this mean for me? Which window should I choose?
The window with the most energy efficiency is an extruded aluminum triple-glazed window with a wood frame. These frames are solid and can support the weight of the heavy glass in this kind of window, without the wear and tear you’d see on a vinyl frame with a triple-glazed window. But they are expensive. They also have more condensation due to their high energy efficiency, which can be alarming for the first season, but isn’t cause for concern.
The best value if you have a more limited budget is a vinyl window, double-glazed, with a low-e 270 I89 coating. As mentioned above, it gives you triple-glaze performance in a lighter window.