Volume 49, Issue 1- January 2014
After Four Years, Non-Residential
In December the NFRC hosted a webinar, “Meeting Commercial Fenestration Code Compliance,” during which time McGowan challenged more of the nation’s commercial glass and window manufacturers to register with the Component Modeling Approach (CMA) Product Certification Program that enables whole-product energy performance ratings for commercial (non-residential) projects.
McGowan said energy lost through windows represents “four to five percent of total U.S. energy consumption at a cost of $50 billion,” according to the Lawrence Berkeley National Laboratory.
“So it’s really important the windows perform well,” McGowan said, stressing not only that such verification is sound business, but also the law in many cases.
“[The rating systems], he said, are “the only way to ensure a building performs at its best and complies with the law.”
McGowan also noted that both CMA and the NFRC Ratings System for residential homes not only cover NFRC 100 and NFRC 200 documents, but also that both systems are user-friendly and easily accessible.
The CMA program offers information on fenestration systems’ primary components—glazing, frame and spacer—through an online database. Each system varies somewhat in the U.S., depending into which of the eight different climate zones a product falls, according to McGowan. The third-party verification system shows how changing one component affects overall energy efficiency and provides information on which components can be combined. The cumulative information, which includes a breakdown of the 2009 International Energy Conservation Code (IECC) and ASHRAE 90.1-2007 fenestration energy requirements for commercial construction, is then used to determine a whole-product energy performance rating for a fenestration system.
he development of the CMA program, which was fully implemented in 2010, was not without objection by the commercial industry. One of the commercial market’s arguments, among others, was that a program created for standard residential products couldn’t be appropriately adapted for a commercial segment that already works to create the most energy-efficient projects using products custom-made for the majority of jobs. With CMA, a custom system must be tested individually for certification, a process that, some say, can be time-consuming and expensive.
“I know for [our company], since our niche products, such as fire-rated glazing and channel glass, make up such a small percentage of the exterior skin on any given project, owners are finding it tough to justify the costs of NFRC certification,” says Chuck Knickerbocker, curtainwall manager with Technical Glass Products (TGP) in Snoqualmie, Wash. “There are work-arounds in some of the codes for windows without NFRC certification. When you’re dealing with less than one percent of the total envelope, we’re not often asked for NFRC certificates.”
Knickerbocker adds that not all of the glass manufacturers have entered their products into the NFRC database.
“That means that part of the NFRC equation can’t be filled in, and therefore the certification can’t be completed. Since the rated windows come as a package deal, we can’t change glass manufacturers; otherwise our UL-rated windows won’t receive their UL-certification. In the case of TGP’s products addressing life safety issues, the UL label is more critical to our end users than the NFRC certification, at present.”
He continues, “The larger glazing contractors do a good job of supporting their products through their technical services departments, and can more easily complete computer thermal modeling of projects. Since this tends to be more real world than the assumed 80- by 80-inch window NFRC uses as a test specimen, the owners and architects aren’t pressing for certification. The actual curtainwall models result in lower U-Values than the NFRC test specimens, given the larger glass area.” Knickerbocker is also quick to point out that NFRC certification is not the only means for the industry to provide evidence of products’ energy performance.
“We, both TGP and the industry as a whole, can do thermal computer modeling that’s 99 percent accurate. Granted, the lab/physical testing can prove that the modeling is accurate,” says Knickerbocker. “Right now, the owners and architects are rolling with the computer modeling and testing that’s currently going on.”
Mike Turner, vice president of marketing with YKK AP in Austell, Ga., adds that for the majority of projects in which his company is involved they continue to see the market employ the American Architectural Manufacturers Association’s (AAMA) 507 Certificate of Compliance as a means to document the thermal performance of commercial fenestration systems.
“While our company supports the CMA process when required on projects, the CMA process is still complex and many are not aware of the certification fees associated with the program,” says Turner. “Glazing contractors have to be very diligent when bidding projects that require CMA certification so that the fees associated with the certification process are covered in their bids. I believe this is why the AAMA 507 Certificate of Compliance is the preferred industry method as it provides the necessary information to ensure products comply with codes and project specifications without the complex process and fees associated with CMA.”