Industry Prepares for New Energy Star Criteria

Biggest challenge for most manufacturers likely to be new U-factor requirements
By Ric Jackson, Quanex Building Products
April 18, 2012
FEATURE ARTICLE | Codes & Standards, Energy Efficiency, Materials & Components

The fenestration industry is facing significant changes that will likely increase thermal performance standards by 30 percent to 40 percent within the next few years. Higher performance levels are demanded by the International Energy Conservation Code and the ICC 700 National Green Building Standard, and soon the Energy Star Windows, Doors & Skylight program.

The Environmental Protection Agency, which is now in charge of the Energy Star windows program, released its proposed changes to the performance criteria this past fall in the Version 6.0 Specification Framework Document. Seeking feedback from industry and other stakeholders in the program, EPA issued proposals for new window U-factors and solar heat gain requirements across the Energy Star climate zones (Table 1). It also highlighted potential additions to the program, including a maximum air leakage requirements and requirements for detailed installation instructions for qualified products. This article focuses on the window criteria, but the document also included new proposals for Energy Star doors and skylights.

 Table 1

Among the proposed changes, the biggest challenge by far for most window manufacturers is the Northern climate zone U-factor proposal set 0.25 and 0.27. Based on our analysis of double-hung windows in the National Fenestration Rating Council’s certified product directory in November 2011, almost 45 percent of participating manufacturers–active and inactive–would not qualify at 0.27, which we think is the likely target that will be used. Not all of those manufacturers sell into the Northern zone.

The second biggest concern is the timing of the Version 6.0 roll-out. The current Energy Star criteria, Version 5.0, took effect in 2010, less than two years ago. The new criteria were initially scheduled to take effect in 2013. EPA has pushed its timetable back somewhat, but many companies have said it is still too short for them to develop new products.

For some manufacturers, it will be relatively simple to make the necessary changes but for some with older designs, it may require an entirely new window system. Based on work we have done using the Quanex Optimizer, we find even the best hollow-frame vinyl window systems will require either triple glazing or thermally-enhanced (foam filling) profiles to meet the requirement.

Some frame materials will struggle to accommodate the change for the Northern zone target. Already, there is almost no residential aluminum product sold in this part of the country.

We would expect that many manufacturers will try to avoid triples if possible due to increased liability that comes with two sets of edge seals, as well as the concerns of weight and hardware modifications.

Whether triples are needed would depend on how close a window is to meeting the new numbers. Warm edge spacers can have an impact on a U-factor between 0.01-0.02, depending on what the manufacturer is currently using. Triples can have as much as a 0.04 impact–even more if a surface 6 hardcoat is used. Doubles with surface 4 hardcoats can achieve equivalent to normal triples with two surfaces of low-E. Triples may, however, be the most cost effective solution for many.

U-factor requirements are changing for the other Energy Star climate zones too, but they should be less of a challenge for manufacturers. We think that the .30/.30 tax incentive for 2009 and 2010 that came out of the stimulus package drove 0.30 U-factor capability all over the country. Since no U-factor requirement outside the Northern zone is lower than 0.30, most companies are prepared to offer windows with that level of performance.

The Version 6.0 Energy Star criteria include some additional requirements for window manufacturers. First is an air infiltration rating requirement of less than or equal to 0.3 cfm/ft². That does not appear to be that challenging based on feedback EPA has received.

Another proposed addition is the requirement for installation instructions to be made readily available. That does not seem to be an issue for most manufacturers, and those companies that are AAMA-certified members or participating in the WDMA hallmark certification program have access to generic installation instructions.

Regardless of the Version 6 changes that take place, many companies are expressing concern about the cost and frequency of testing and a new verification program which will seek to verify up to 10 percent of the commercially-available certified products annually.

 In some Energy Star product categories, EPA recognizes a top-tier "Most Efficient" performance level. Some in the industry would like to see such a designation added for residential windows.

While the Version 6.0 U-factors may be a challenge for the industry, there are reasons to believe even more stringent numbers are inevitable for the future. At the current performance levels, the market is saturated with Energy Star-qualified windows and it is almost impossible to find a non-Energy Star-labeled product. (Ducker estimates more than 80 percent of the windows sold were Energy Star in 2011).

We think, in general, most of the window industry supports the idea of more than one level of performance to allow window companies that have superior performing products for differentiation. EPA has stated as far back as 2010 that a best in class tier might be created called “Most Efficient” under Energy Star for windows. Such a tier would be aimed at highlighting the 5 percent of products with the highest performance. In the comments from the Framework Proposal, a few large national manufacturers cited this as a good approach.

Differentiation in the current market is very difficult to maintain. We think that is why so many companies built R-5 products when the Department of Energy launched its R-5 volume purchase program. They may not have participated in the program, but we count 157 manufacturers that have R-5 or better in NFRC’s certified product directory. For these companies, it will be important to be able to show superior performance.

A sidebar to this article examines the growing importance of the Energy Star Homes program and the opportunities it may provide to the window and door industry. 

If the government wants to maintain Energy Star’s reputation with consumers, it has to change to more aggressive targets for the base program or by adding a more aggressive tier like Most Efficient. More changes will come, so manufacturers not currently able to achieve at least a 0.25 U-factor should seek the counsel of trusted suppliers to find the right mix of glass, low-E coatings, gas fill, warm edge spacers and framing material to achieve optimal performance at the optimal cost.

Without overstating the obvious, the building and construction market has undergone some drastic changes over the past five years. Like a meteoric strike, the Great Recession forced many of us to adapt. Where there was once a flourishing sea of fish, only those manufacturers, distributors and dealers who found a way to grow legs remain–and, in some cases, are poised for continued prosperity.



Ric Jackson is the director of external affairs for Quanex Building Products. Based in Houston, the company's operations produce the Super Spacer and Duraseal line of IG edgeseal products, Mikron vinyl and composite window profiles, and a variety of other fenestration products through its Homeshield business. Jackson's areas of interest and specialty include the development of industry standards and government relations. He can be reached at