Understanding Window Labels
National Fenestration Rating Council (NFRC) certified products are independently tested, certified, and labeled to help you make the best purchase decision for your needs. While the ENERGY STAR label tells you if a product is energy-efficient, the NFRC label helps you compare between energy-efficient products by breaking down a product’s energy performance. The NFRC label helps you compare between energy-efficient windows, doors, and skylights by providing you with energy performance ratings in multiple categories. U-Factor measures how well a product can keep heat from escaping from the inside of a room. The lower the number, the better a product is at keeping heat in. Range: 0.20–1.20 Look for: Low numbers Solar Heat Gain Coefficient measures how well a product can resist unwanted heat gain, which is especially important during summer cooling season. The lower the number, the less you’ll spend on cooling. Range: 0–1 Look for: Low numbers Visible Transmittance measures [...]