Air leakage is a very important consideration when choosing your new windows and who will install them. This factor is just as important as the window’s U-factor and solar heat gain coefficient. What is it and why does it matter when looking for replacement windows? Renewal by Andersen® of Phoenix discusses the answers here.
What Is Air Leakage?
Air leakage, or air infiltration, is the amount of air that passes through cracks in the window assembly, as well as the amount of air that leaks through the window frame due to window installation and sealing failures. The more air that can leak through a window, the less energy-efficient that window will be.
Air leakage ratings are calculated by measuring the amount (in cubic feet) of air that can pass through a window within a minute, then dividing that amount by the total window area. The smaller the number, the more energy-efficient that window will be. ENERGY STAR and the NRFC considers ratings below 0.3 as energy-efficient.
Determining the rating has to be done before installing windows. Arriving at a rating, however, is a bit tricky. Some window companies might misinterpret the rating by comparing windows of different sizes. It’s also worth noting that air infiltration ratings are based on a wind speed of 25mph.
Why Does the Air Leakage Rating Matter?
The average home spends up to 30% more on cooling and heating expenses when air leaks through windows. Getting the right window, with air infiltration ratings below 0.3, then, will help you save more money in the long run.
Not all windows have their ratings displayed, though. Sometimes, the NFRC won’t recognize ratings below 0.1. This is because windows with low air leakage ratings might not have any significant differences enough to tell them apart.
Sometimes, however, window companies are the ones who refuse to display their air leakage ratings. This could be because air leakage ratings aren’t really required. Buyers should watch out for windows with no ratings.
Looking for a casement, double-hung or bay window that won’t leak a lot of air into and out of your home? Get in touch with Renewal by Andersen of Phoenix by calling us at (602) 772-5059 or fill out our contact form for a free, in-home, no obligation consultation. We serve clients in Phoenix and Tempe, AZ.