Understanding the ENERGY STAR® Label

April 23rd, 2019 by

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In an effort to promote efficient energy use in homes and businesses nationwide, the Environmental Protection Agency (EPA) along with the Department of Energy compiled a comprehensive list showing the energy utilization performance of different appliances, furnishings and devices. Thus, in 1992, ENERGY STAR® was born.

The ENERGY STAR label allows consumers to identify products with good energy efficiency ratings. When it comes to window replacement products, ENERGY STAR uses the performance standards set by the National Fenestration Rating Council (NFRC) for evaluation. Let our experts at Renewal by Andersen® of Portland give you a quick overview of these standards to help you gain a better understanding of your own efficiency performance.

Solar Heat Gain Coefficient (SHGC)

This measures how much heat a window’s glazing can effectively block. The SHGC is presented as a decimal between 0.25 and 0.80. The lower this number is, the better your windows will be at keeping your home cool even on hot days.

ENERGY STAR requirements for the SHGC of window replacement products vary from one region to another. For homes in Portland, you want to keep this number between 0.40 and 0.60 for optimum efficiency during hot summer days.


Insulation plays an equally important role in maintaining your energy efficiency. This is measured in decimals between 0.25 and 1.25, similar to the SHGC. Lower U-factor numbers mean better insulation for your windows.

The climate in Portland can swing wildly from hot, humid summers to cold winters, which means that to maintain energy efficiency, you want a window replacement U-factor of around 0.23 to 0.30.

Renewal by Andersen of Portland is your number one resource for all your door and window replacement needs. Call us at (503) 419-3960 or fill out our online contact form to schedule a free in-home design consultation and request a no-obligation estimate today. Our services are available in Portland, OR, as well as some areas in Vancouver, WA.