Understanding NFRC Energy Performance Ratings

The National Fenestration Rating Council (NFRC) label contains metrics that show how well windows could keep your home from becoming overly hot or cold year-round. Understanding energy performance ratings allows you to choose the perfect products for your local climate.


NFRC Energy Performance Ratings

How do you distinguish energy saving windows from low-performance ones? Jones and Associates explains the measurements you’d see on the NFRC label:




This metric refers to the product’s overall thermal insulation property. Ranging from 0.20 to 1.20, the lower low U-Factor values, the better the window is at preventing the heat from escaping out of the room.


Solar Heat Gain Coefficient (SHGC)


The SHGC talks about inhibiting heat’s entry, in contrast to the U-Factor. It measures how well the window can reflect the sun’s infrared rays to prevent unwanted heat gain. Ranging from 0 to 1, the lower the SGHC values, the less you’d spend on cooling.


Visible Transmittance


This metric pertains to the ability of the unit to allow visible light through. The best energy saving windows let in the most natural light they could catch. Also expressed in 0 to 1, the higher the value, the better the product is at promoting daylighting. Therefore, the more you can potentially save on artificial lighting.

Air Leakage


This measurement tells you how airtight the window is. Ranging from 0.1 to 0.3, the lower the number, the less you’d get undesirable drafts.


Knowing what these ratings mean is paramount in choosing the right energy saving windows, but it’s more complicated than that. The type of unit, its size, and your home’s orientation to the sun are also key considerations to ensure maximum energy efficiency. You need an experienced window replacement company that could evaluate your situation and offer you sound recommendations.


At Jones and Associates, our proficiency and experience give you tremendous mileage in tackling your window replacement right. To guarantee the success of your project in Lubbock Midland, or Odessa, TX, call us at (806) 686-1380 for your FREE, in-home consultation and estimate.


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