Proposal to Make AAMA 507 an Alternative to NFRC Rating Defeated

The National Fenestration Rating Council (NFRC) and the glazing industry sparred again, metaphorically speaking, at the International Code Council (ICC) hearings, and NFRC was the winner. The hearings started February 18 in Palm Springs, Calif., and will go through March 1.

The proposed change before the group, EC4-07/08, was introduced by five industry personnel, including Margaret Webb of the Insulating Glass Manufacturers Alliance (IGMA) and Greg Carney of the Glass Association of North America (GANA). Their proposed changes began with section 102.1.3 on fenestration product ratings, where they wanted to see the text referencing specific group code and charts deleted and in its stead simply have the section reference individual subsections where the meat of the group code is addressed.

Subsequently, the group-of which Craig Conner with Building Quality, Julie Ruth of JRuth Code Consulting (representing the American Architectural Manufacturers Association [AAMA]) and Rand Baldwin for the Aluminum Extruders Council are also part—proposed the addition of these subsections:

102.1.3.1 Fenestration rating by NFRC [National Fenestration Rating Council] 100 and NFRC 200. Determination of U-Factors for fenestration products shall be in accordance with NFRC 100 by an accredited, independent laboratory, and the products shall be labeled and certified by the manufacturer. Determination of the [solar heat gain coefficient] SHGC of glazed fenestration products shall be in accordance with NFRC 200 by an accredited, independent laboratory, and the products shall be labeled and certified by the manufacturer.

102.1.3.2 Commercial fenestration alternative rating by AAMA 507. U-factors and SHGC for fenestration used in commercial buildings shall be determined in accordance with AAMA 507. The product performance shall be documented by a certificate of compliance, as described in AAMA 507, that is signed and submitted to the code official by the glazing contractor or registered design professional. The product line testing and simulation, as described in AAMA 507, shall be conducted in accordance with NFRC 100 and NFRC 200 by an approved, accredited, independent laboratory.

102.1.3.3 Default values for fenestration rating. Products lacking a U-factor determined in accordance with Section 102.1.3.1 or 102.1.3.2 shall be assigned a default U-factor from Table 102.1.3(1) or 102.1.3(2). Products lacking an SHGC determined in accordance with Section 102.1.3.1 or 102.1.3.2 shall be assigned a default SHGC from Table 102.1.3(3).

They proposed the addition of curtainwall and storefront glazing to the definition of fenestration as used in Section 202's general definitions and would like to see the addition of an AAMA standard (507-07, "Standard Practice for Determining the Thermal Performance Characteristics of Fenestration Systems Installed in Commercial Buildings") to Chapter 6.

Connor provided the first written reason for the group's proposal: "The reason for this change is simple. Commercial windows should be rated for energy-efficiency. The industry needs a rating method that works with their bid and construction process. The time between bid and construction can be days or weeks. The NFRC website states, 'It will take on average approximately 100 days to obtain a Label Certificate.' The AAMA 507 procedure can be used to rate a window within a few days or less and produces the same rating."

Ruth added that "[this] proposal would permit the use of AAMA 507 to determine the U-factor and SHGC of glazed assemblies in commercial buildings … We urge the committee to recognize this method in the IECC to provide architects and contractors an accurate way to determine the U-factors and SHGC of a proposed glazing system that fits within the fast track time frame of commercial construction."

The proposal was defeated by 10 to 4 after two modifications to it were approved. These modifications said that the proposal only applied to curtainwall and storefronts and that the glazing contractor could not supply the certificate of compliance; it could be done only by a design professional.

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