What Is Air Leakage and Why Does It Matter?

When you shop for energy efficient windows, one of the things you need to consider is their energy performance ratings. These are helpful in understanding the windows’ capability to gain or lose heat, as well as bring sunlight into your home. You will come across terms such as U-factor and solar heat gain coefficient (SHGC), but did you know that there’s also an air leakage (AL) rating? California Energy Consultant Service, your trusted window replacement contractor, discusses more. 

What Is Air Leakage?

Air leakage, also called air infiltration, refers to the rate of air movement around a window in the midst of a specific pressure difference across it. The value of this rating is determined before installation, which is why you must make sure that the windows you purchase are professionally installed to keep that number where it is.

Air leakage in windows is measured on a scale of 0.1 to 0.3. The lower the number, the more energy-efficient the window is. An energy-efficient window is designed to prevent conditioned air from exiting your home and has greater insulation, lowering your energy consumption and expenses while improving the overall comfort of your home.

The Importance of the Air Leakage Rating

Air leakage isn’t seen as a necessary rating like the U-factor and SHGC. Then again, it is likely you’ll find this particular rating when you read the blue-and-white ENERGY STAR® labels in replacement windows. As long as the number is lower than 0.3, you can be sure that the National Fenestration Rating Council (NFRC) and ENERGY STAR determine the windows to be energy efficient.

California Energy Consultant Service is a leading provider of home energy efficiency solutions, including energy assessment and residential window replacement. Call us at (916) 993-5000 or fill out our contact form to schedule a free consultation today. We serve residents in Sacramento and Rancho Cordova, CA, as well as the surrounding communities.