NFRC Fenestration Simulation and Validation

Window, Door, and Skylight Manufacturers certify their windows to The National Fenestration Rating Council (NFRC) for Energy Performance Ratings using a thermal validation test and a thermal simulation. Fenestration product NFRC thermal performance ratings are specified by the International Code Council (ICC) building codes, including the “International Residential Code” (IRC), the “International Energy Conservation Code” (IECC), and the “International Building Code” (IBC). NFRC ratings and certification are also used to demonstrate compliance with the ENERGY STAR Windows Program.

Element is a fenestration testing laboratory. Element Engaged Experts prepare similar thermal simulations using the software programs THERM and WINDOW. These simulations determine the Fenestration Product U-Factor, Solar Heat Gain Coefficient, Visible Transmittance, and Condensation Resistance.

After the thermal simulations are complete, a physical validation test, NFRC – 102, is conducted following the ASTM C1199andCalibration Transfer Standard (CST) methods. With NFRC – 102, the window, door, or skylight is mounted in a panel and placed against an opening in the environmental chamber (cold side). A hot box or, “Metering Box” is then placed against the window covering creating an interior environment similar to the inside of a house. Measured in Standardized U-Factor (UST), the physical test determines the factors:

• service and air temperature
• humidity
• wind speed
• energy usage (with an absence of solar radiation)
• air leakage effects

Additional standards we follow include the following:

• ANSI/NFRC 100: “Procedure for Determining Fenestration Product U-Factors”
  • Measures how well a product can prevent heat from escaping from inside a room.
• ANSI/NFRC 200: “Procedure for Determining Fenestration Product Solar Heat Gain Coefficient and Visible Light Transmittance at Normal Incidence”
  • Solar Heat Gain measurement tells the consumer about unwanted heat gain through the fenestration product. This is especially important in summer months or the cooling season.
  • Visible Light Transmittance: During daytime hours, how will the product light your home.
• NFRC 500: “Procedure for Determining Fenestration Product Condensation Resistance Values”
  • Determines How well does the product resist condensation

A conversation with one of our Engaged Experts will provide certainty that our fenestration testing laboratory will meet your needs. For more information, please contact us to US +1 888 786 7555 or UK +44 808 234 1667.