Alternative nonresidential energy-rating program advances to code hearings

In the future, nonresidential fenestration system manufacturers could have a choice of two thermal performance rating procedures, if a proposal backed by several industry associations passes through the International Code Council’s code hearings in September.

Leaders of the Glass Association of North America of Topeka, Kan., and the Aluminum Extruders Council of Wauconda, Ill., figure prominently among several proponents supporting the addition of the American Architectural Manufacturers Association’s AAMA 507-03 to the International Energy Conservation Code, says Ken Brenden, codes and industry affairs manager for AAMA in Schaumburg, Ill.

AAMA 507-03 defines AAMA’s standard practice for determining thermal performance of nonresidential fenestration systems, Brenden explains.

The current IECC code only recognizes use of NFRC 100, an energy-rating system from the National Fenestration Rating Council in Silver Spring, Md., and requires determination of thermal performance values by use of default tables included in the IECC or labeling in accordance with NFRC 100.

“There is an International Building Code-IECC code proposal going forward that permits the use of this method as an alternative—not substituting or replacing—NFRC 100,” Brenden says.

While the alternative-methods provision in the IECC already permits use of AAMA 507-03 if a code official determines it meets the intent of the code, NFRC officials say they don’t support writing it into the code as an official alternative.

Multiple procedures for determining thermal performance of fenestration systems could lead to confusion in the industry, says Jim Benney, NFRC executive director.

“NFRC sees no need for another rating system—whether it’s alternative or competitive,” says Benney. “It’s not in the best interest of the public or industry to have multiple methodologies. … NFRC already provides a single, reliable system that contains adequate checks and balances.”

Greg McKenna, technical consultant for Kawneer Co. in Norcross, Ga., says manufacturers could benefit from having a choice of ratings systems.

“It would make NFRC 100 a better procedure because it would give it some competition, and [NFRC leaders] would have to address the concerns that manufacturers have,” McKenna says. “It is not a user friendly procedure.”

The AAMA 507-03 relies on methods in NFRC 100 to define system values. However, it does not require third-party certification, allowing manufacturers a single simulation to calculate the ratings for various combinations of glass and frame options, McKenna says.

Thomas Culp, owner of Birch Point Consulting in La Crosse, Wis., says the complex nature of many nonresidential projects makes an alternative necessary.

“NFRC 100 works quite well for standard factory-assembled products. … However, the current NFRC procedures are not well suited to the commercial market, especially for field-assembled fenestration where several parties are involved,” Culp says. “The NFRC procedure becomes very cumbersome and expensive.”

Culp anticipates some objection from NFRC officials during the code hearings.