The NFRC rating sticker should be on every window you purchase whether it is a replacement window or new construction. The purpose of this sticker is to show you how well a window performs in various areas relative to the energy efficiency of the window. Performance is based on laboratory evaluations of the window’s frame, glass, and spacers that separate the individual glass panels.
National Fenestration Rating Council (NFRC)
Below are some of the factors that are labeled on the NFRC sticker and what they mean.
U-Factor – The U-factor is resistance to heat flow. It measures the insulating performance of the entire window. A lower U-Factor is always better than a higher U-Factor and often directly translates into a more comfortable home and lower energy bills.
Solar Heat Gain Co-Efficient – The SHGC measures how much infrared light gets thru the glass. To better understand this, think about the different you feel when sitting outside in the shade vs. sitting outside in the sun. The additional head you feel from the sun’s rays is the same heat that is blocked by windows with a decent SHGC. The lower the SHGC, the more solar heat is blocked and the easier it is for you to keep your house cool. This is considered more important in warmer climates.
Visible Light Transmittance – This measures the amount of visible light that comes through the glass. A window with dark, tinted glass will have a low visible light transmittance. Most people look for higher visible light transmittancenumbers in order to let to most natural light into their homes.
For more information on what these numbers mean for you please call Affordable Windows and Siding at (859) 519-5338 or visit windowslex.com and we can answer any questions you may have about replacement windows.