The National Fenestration Rating Council (NFRC) launched of a new process to reduce the time needed for simulating, helping get innovative new windows, doors and skylights to market faster. The methodology leverages the simulation process that NFRC has used during 30 years of producing ratings that measure the energy efficiency of fenestration products.

The Linear Energy Analysis for Fenestration (LEAFF) trend line methodology uses product-line characteristics to determine trend lines that replace the need to run numerous simulations separately. This establishes the windows’, doors’ or skylights’ energy performance with different options such as glazing and frame types.

“This is a real game changer,” said Deb Callahan, CEO at NFRC. “Fenestration industry professionals and the public want the most energy-efficient options possible. This streamlined process will save time and make it easier for manufacturers to get new, innovative products certified.”

NFRC is offering a series of online courses open to members and nonmembers that will provide information and instruction on the LEAFF trend line methodology, formerly known as Residential Component-Based Calculation, for energy performance ratings. The course will also provide information on the new Condensation Index, which will replace the Condensation Resistance rating.
All NFRC Certified Simulators, regardless of company’s affiliation, and all Individual Responsible Charge personnel from NFRC-licensed Inspection Agencies are required to attend all phases of training and successfully pass exams to maintain their status. NFRC recommends all individual’s performing or reviewing simulations from an accredited simulation laboratory or licensed inspection agency attend the training. For more information, visit