Are All Energy-Efficient Windows Rated The Same?

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When you're looking for information about residential windows, you'll find the answers to your questions in this blog. We don't sell or install windows ourselves, but we do know a lot about them. We learned by doing our own internet research and by talking to people who make their living in the residential window industry. Some of the answers you'll discover in this blog is how to correctly measure for new or replacement windows, how to choose energy efficient windows and the different styles of windows that are available. You'll also learn how to tell when it's time to replace the old windows in your home. We hope this informative blog helps you make the best choices for your home windows.


Are All Energy-Efficient Windows Rated The Same?

22 May 2020
 Categories: , Blog

If you browse through any catalog of new window options, you are likely to see a common term — energy efficient. You probably have an idea what this phrase means, but in the context of new windows, you likely have a lot of questions. More specifically; are all energy-efficient windows the same? Learn how to differentiate this class of windows to ensure you make the right investment.

Stamp of Approval

A claim of energy efficiency by a window manufacturer is only valid if it has a stamp of approval. This approval comes in the form of certification from the National Fenestration Ratings Council or NFRC. If you do not see a reference to this certification, the term energy efficiency is more or less being used as a marketing method. If you work alongside an installer to choose your windows, you can be confident that your selection has this stamp of approval. 


In terms of distinction, one factor that is used to rate the energy efficiency of a window is its propensity to air leakage. The easier it is for air to escape from inside your home and leak outside, or vice versa, the lower the rating for the window on the scale. High amounts of air leaks lead to temperature instability inside your home, which can drive up your heating and cooling costs. 


Investigate the U-Factor of the window to assess its energy efficiency rating. If you live in a colder climate, this measure is important because the U-Factor is a gauge on how well the window is able to keep heat inside. The higher a windows' rating in this category, the easier it is for the warmed air inside a home to transfer through the glass. Therefore, during the winter, the heated air will escape through the windows. 

Solar Gain

Solar gain functions opposite of the U-Factor. This rating is one that is based on the rate at which warm air from outside can leak through the windows and into your home. If you live in a hot climate, you want to pay extra attention to this measure. Truly energy-efficient windows are those with a low figure of solar gain because the larger the number, the greater amount of heat rays that can transfer through the glass.

If you have more questions about classifying the different ratings for energy-efficient windows, an installer like A United Window Inc., can help. Speak with a professional to learn more about these window options and to choose the ideal option for your needs.