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This tool provides some of the most common options on windows and doors and related NFRC values. For more information about the energy efficiency of specific products and options, please contact your local Marvin sales representative.
The National Fenestration Rating Council (NFRC) has developed and operates a uniform national rating system for the energy performance of fenestration products, including windows and doors. For additional information regarding this rating system, see www.nfrc.org/WindowRatings.
See Energy Efficient Windows and Doors for further information on this topic.