The National Fenestration Rating Council (NFRC) is a non-profit organization that provides energy performance ratings for windows, doors, and skylights. The organization’s focus is to empower consumers with the knowledge to make informed purchasing decisions when it comes to energy-efficient windows.
The NFRC uses independent, third-party testing organizations to evaluate the energy performance of fenestration products. This evaluation generates a set of measurements and ratings that homeowners and contractors can use to compare the energy performance of different products. The ratings include U-factor, Solar Heat Gain Coefficient (SHGC), Visible Transmittance (VT), Air Leakage (AL), and Condensation Resistance (CR). This article will delve into the specifics of these ratings.
U-factor: U-factor is a measurement of how much heat is lost through the window or door. A lower U-factor means less heat is lost and better insulating properties. U-factor is measured on a scale from 0.20 to 1.20, with lower numbers indicating better performance.
Solar Heat Gain Coefficient (SHGC): SHGC measures how well a window blocks heat caused by sunlight. A lower SHGC means less heat transfer and better energy efficiency. SHGC is measured on a scale from 0 to 1, with lower numbers indicating better performance.
Visible Transmittance (VT): VT is a measurement of how much light passes through a window. A higher VT means more natural light indoors. VT is measured on a scale from 0 to 1, with higher numbers indicating better performance.
Air Leakage (AL): AL indicates the amount of air that leaks through the window or door. A lower AL means less draft, better energy efficiency, and better insulation. AL is measured in cubic feet per minute per square foot (cfm/ft2), with lower numbers indicating better performance.
Condensation Resistance (CR): CR is a rating of a product's ability to resist condensation. A higher CR means the product is less prone to condensation. CR is measured on a scale from 1 to 100, with higher numbers indicating better performance.
When purchasing windows, doors, or skylights, it is essential to look for products that comply with NFRC ratings. The ratings provide clear, measurable performance indicators that simplify the process of comparing different products. Keep in mind that the product’s climate zone is also essential to consider. The climate zone ranges from 1 to 8, with 1 being the coldest and 8 being the hottest. Products that perform well in one climate zone may not perform as well in another climate zone.
Overall, the NFRC rating system is an essential tool for homeowners, contractors, and architects looking to improve their home or commercial building’s energy efficiency. By selecting products that conform to NFRC ratings, property owners can take a significant step towards lowering their energy costs and reducing their carbon footprint.
