It is through our laboratories, under the auspices of the Laboratory Accreditation Program (LAP) to accredit simulation and testing laboratories to conduct computer simulation and physical testing that the certified and labeled fenestration product is rated for U-factor, Solar Heat Gain Coefficient (SHGC), Visible Transmittance, Condensation Resistance/Index, and Air Leakage.

NFRC accredited laboratories undergo extensive auditing procedures to ensure confidence that the laboratories’ produce credible and accurate results and without bias.

Contact Dennis Anderson for more information. 

Testing Laboratories, those that physically test fenestration products, are an integral part of the fenestration product certification. The thermal transmittance (U-factor) laboratories are contracted by the fenestration manufacturer to validate their product line. Validation is achieved by comparing the physical U-factor test (NFRC 102) to the same simulated option. If they are in tolerance, the entire product line of simulated results are “validated.” When products cannot be simulated, the NFRC has accreditation procedures to for laboratories to physically test for solar heat gain via NFRC 201, visible transmittance via ANSI/NFRC 202 and ANSI/NFRC 203, and sometime NFRC 102 for products such as Garden or Glass Block windows. Air leakage ratings cannot be simulated so this is a test-only situation and manufacturers may achieve this rating via ANSI/NFRC 400 by an NFRC-accredited laboratory or an NFRC-recognized air leakage laboratory.

Simulation Laboratories employ NFRC certified simulators that generate the computer simulated results for the fenestration manufacturers. Certified simulators, as part of the LAP, attend an extensive certification workshop and must pass examinations before they achieve the status of NFRC Certified Simulator. The NFRC conducts the rigorous certification workshop annually and we have many that attend every year, to include but not limited to laboratories, consultants, manufacturers, and inspection agencies. We list all that have successfully become NFRC Certified on our website and they must maintain their certification every year.  Maintenance of the simulation certification requires participation in an annual Interlaboratory comparison and attendance to mandatory training workshops.