NFRC Window Ratings | Energy-Efficient Windows & Doors | NuImage

The National Fenestration Rating Council (NFRC) provides energy performance ratings for windows, doors, and skylights, helping consumers choose the most efficient options for their homes.

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U-Factor – Measures how well a window prevents heat from escaping. A lower U-factor means better insulation, which helps keep homes warm in colder climates and reduces heating costs.

Solar Heat Gain Coefficient (SHGC) – Indicates how much solar heat passes through the window. A lower SHGC blocks more heat, keeping interiors cooler in warm climates, while a higher SHGC allows more warmth in colder regions.

Visible Transmittance (VT) – Determines how much natural light a window lets in. A higher VT increases daylight, reducing the need for artificial lighting and enhancing indoor brightness.

These ratings allow homeowners and builders to compare products and select windows that best suit their climate and energy needs.