National Fenestration Rating Council
The National
Fenestration Rating Council (NFRC) is a nonprofit, public/private organization created by the window,
door, and skylight industry. It is composed of manufacturers, suppliers,
builders, architects and designers, specifiers, code officials, utilities, and
government agencies. The NFRC has developed a window energy rating system based
on whole product performance.
The NFRC label provides the only reliable way to determine the window energy properties and to compare products. The NFRC label appears on all products certified to the NFRC standards and on all window, door, and skylight products which are part of the ENERGY STAR® program. At this time, NFRC labels on window units give ratings for U-factor, Solar Heat Gain Coefficient (SHGC), Visible Light Transmittance (VT), and Air Leakage (AL). Soon labels will include a Condensation Resistance (CR) rating.
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U-factor | |
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Solar Heat Gain Coefficient | |
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Visible Transmittance | |
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Air Leakage |
U-Factor | Solar Heat Gain Coefficient | Visible Transmittance | Air Leakage
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