Winter  2006


Glass Tech

    Thermal Performance Certification: Cost vs. Value
By Greg Carney

Architects and builders primarily involved in residential construction are probably familiar with the National Fenestration Rating Council (NFRC) and its energy rating and labeling system for residential windows, doors, and skylights. However, those involved in commercial construction are considerably less familiar with the organization. Commercial window walls, curtainwalls and sloped glazing systems historically have not been affected by the NFRC’s residentially focused programs. 

However, NFRC is in the process of developing a commercial fenestration rating and certification program, and members of the glass industry are questioning its need and the cost impact it would have for building owners and developers.

In 1999 NFRC implemented a site-built rating and certification program to address the commercial building industry. Though the program was based on software simulation tools commonly used in both the residential and commercial fenestration industries, it lacked substantial input from the members of the commercial segment and was met with limited acceptance. NFRC subsequently has acknowledged that the site-built program had “…drawbacks limiting its usefulness.” 

In 2004 NFRC began development of a component-based product certification program intended to replace the site-built one and better serve the commercial fenestration industry. Commercial industry members voiced concern that building owners and design professionals had not expressed a need for the program and, therefore, were likely to question the cost value of the rating and certification. NFRC membership segments from code and energy conservation organizations have stressed that the program is needed to ensure future code compliance. 

During the 2005 NFRC Spring Membership meeting, its board of directors advised that a primary goal of the new program was to “demonstrate real, tangible, and cost effective value to nonresidential end-users.” Commercial industry members have stressed this goal during five task group meetings in 2005; however, cost concerns remain. 

While the program and associated costs have not been finalized, 2002 NFRC-projected costs for rating and certification of commercial wall systems provided in Table 1 exceeds $10,000 per project for three of the five examples. And these projections do not include fees for glazing contractors, general contractors or architects likely to be involved in the process.

Such a rating and certification program would not add performance to a wall system as the commercial construction industry already documents product performance through project specifications and contractual documents. Additionally, building owners seem unlikely to embrace a program which adds tens of thousands of dollars in costs. If the commercial construction industry is mandated to use the rating and certification program to comply with energy codes, unreasonable fees could result in building owners choosing merely to meet the energy requirements in lieu of striving to build energy efficient buildings that exceed the codes. 

Members of the commercial fenestration industry will continue to play an active role in challenging the NFRC to meet its goal of developing a program that will provide “cost effective value,” however, input from the architectural community and building owners is also needed. 

For additional information, visit NFRC or the Glass Association of North America (GANA)

Greg Carney is technical director of the Glass Association of North America. He is an active participant in ASTM International, the Glazing Industry Code Committee, National Fenestration Rating Council and Protective Glazing Council. He chairs the NFRC Non-Residential Products (Ratings) Subcommittee.

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