A-Rated Windows

By using the information contained on the label, builders and consumers can reliably compare one product with another and make informed decisions regarding the energy performance of window products.

The basic label lists the manufacturer, describes the product, includes the essential energy performance data and provides a source for additional information.

Energy Rated WindowsThe BFRC Window Energy rating System lets you know that you are buying the right products. It helps you to quickly select energy efficient windows for your home by comparing window ratings. To view our products Energy Ratings click here.

  • A-Rated Windows
  • Thermal Transmittance (U-value)

    This measures how well a product prevents heat escaping.
    The energy rating value is based on a standard window to enable comparison of product.

    Solar Factor (g-value)

    This measures how well a product blocks heat caused by sunlight. The Solar Factor is expressed as a number between 0 and 1. A lower Solar Factor means less heat gain.

  • Air Leakage (L50 value)

    The factor L50 in the formula is an air leakage factor. For good quality windows, air leakage makes little difference to energy performance, for leaky windows, the impact is significant.