Understanding the U-Factor for Replacement Windows: The Importance of a Low Score and How This Affects Your Home

Understanding U-Factor for Replacement Windows

One of the major performance rating categories listed on an NFRC label is the U-Factor, which is also sometimes called the U-Value. This category measures the rate of heat transfer from the inside of a home to the outside. While the scientific measurements that go into calculating a U-Factor can be rather complex, all that a homeowner really needs to know is that a lower U-Factor means that less heat will be able to pass through the glass.

The ENERGY STAR® standards for U-Factors vary slightly from region to region, so determining what would be an ideal U-Factor for your home depends on which part of the country you live in. In the northern part of the United States, energy-efficient windows often have U-Factors that are as low as 0.17. This is because the less heat that is able to escape, the easier it will be for the home to stay warm during the colder months. However, in the southern states, where the climate is generally much warmer and the majority of home energy usage is for keeping homes cooler against a warm outside temperature, U-Factors as high as 0.30 are not uncommon.

Sunrise Windows offers high-performing vinyl replacement windows that feature either double- or triple-pane glazing systems and are equipped with inert gas fills for superior insulation that will help prevent unwanted heat transfer into and out of your home. Our windows boast some of the lowest U-Factors in the industry and can be customized to perform ideally in your local climate, whether it’s hot, cold, or somewhere in between.

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For more information about how a replacement window’s U-factor can affect your home’s energy performance, click here to locate a Sunrise Windows dealer in your area.

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I had ALL my windows and both doors replaced at the same time to my older (built in 1958) home by the folks at Sunrise and am very satisfied with the selection, service and installation! I’d recommend Sunrise to anyone renovating their older home.

As a window salesman who can sell Pella, Marvin, and Andersen windows as well, I can say with confidence that the Sunrise Window is a better option than any of those window brands. Most of the negative reviews I have read about the Sunrise product, is because the homeowner is uneducated on how condensation works, or the fault of the installer. If Sunrise makes a mistake, they will always fix it. Best window company to deal with and best warranty out there.

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Chicago, IL

Installed 30 replacement windows and 2 sliding glass doors in Raleigh, NC. No leaks, no condensation, nearly perfect inside and out. Some windows were larger than 5x5 and still no problems. No more drafts and lower hvac costs. Real quality. Check with experts who engineer glass, as I did. They look great and visitors actually notice and comment. Just a happy customer. Nice job guys!

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Toledo, OH

I had Sunrise Windows installed in my home in 2000. We started noticing some of the wood lament on the windows started peeling. Sixteen years later, Sunrise honored their warranty and replaced every window. This is a stand-up company.

Temperance, MI