High quality replacement windows installed by Homecraft®, Inc. feature advanced technology to help reduce energy loss. This efficiency can actually be measured. And it is, by an independent testing laboratory known as the National Fenestration Rating Council (NFRC). Any replacement window Delaware homeowners purchase should have an NFRC label affixed.
NFRC is an independent, non-profit organization that administers the only nationally accepted rating system for energy performance of windows, doors and skylights. The NFRC provides fair, accurate and reliable energy performance ratings so that architects, engineers, builders, code officials, contractors and homeowners can compare different products and make informed choices.
The NFRC has established industry standards for rating the energy performance of replacement windows, including:
The most important measure of a window’s performance is its U-value. The U-value indicates the rate of heat flow through a window. The lower the U-value, the more energy efficient the window will be. U-value measures the entire window unit — glass, frame, sash, spacers — and is the only measurement accepted by the U.S. Department of Energy’s EnergyStar program.
R-value is the measure of the resistance of glass to the flow of heat. The higher the R-value, the better the glass will be at insulating your home. But R-value is NOT an accepted form of measurement by the NFRC or EnergyStar, as it does not measure the overall window unit.
Solar Heat Gain Coefficient
Solar Heat Gain Coefficient (SHGC) measures how well a product blocks heat caused by sunlight. The SHGC is the fraction of incident solar radiation admitted through a window and absorbed and subsequently released inward. SHGC is expressed as a number between 0 and 1. The lower a window’s solar heat gain coefficient, the less solar heat it transmits.
Visible Transmittance (VT) measures how much light comes through a product. The visible transmittance is an optical property that indicates the amount of visible light transmitted. VT is expressed as a number between 0 and 1. The higher the VT, the more light is transmitted.
Air Leakage (AL) is indicated by an air leakage rating expressed as the equivalent cubic feet of air passing through a square foot of window area (cfm/sq ft). Heat loss and gain occur by infiltration through cracks in the window assembly. The lower the AL, the less air will pass through cracks in the window assembly.
Condensation Resistance (CR) measures the ability of a product to resist the formation of condensation on the interior surface of that product. The higher the CR rating, the better that product is at resisting condensation formation. While this rating cannot predict condensation, it can provide a credible method of comparing the potential of various products for condensation formation. CR is expressed as a number between 0 and 100.
*This rating is optional and manufacturers can choose not to include it.
You will find an NFRC label on every window installed by Homecraft®, Inc. This is independent proof of the quality and energy-saving properties of the window.