An important victory

Jenni Chase
December 6, 2010

Over the past five years, green building has grown to represent 35 percent of all new nonresidential building construction, according to McGraw-Hill Construction, New York. By 2015, that number is expected to increase to 48 percent, with the green building market valued at $145 billion, MHC officials predict. That's a big number, especially in a construction market hit hard by the recent recession.

The glass industry's ability to capitalize on the green building movement relies on more than the government mandates and owner interest driving the trend, however. As Katy Devlin points out in her article, it also largely depends on the building and code community, and its stance regarding the energy efficiency glass brings to the table.

Case in point: The industry dodged a bullet this fall when the American Society of Heating, Refrigerating and Air-Conditioning Engineers, Atlanta, reversed a decision that would have greatly reduced the amount of glass allowed in commercial buildings. ASHRAE's Standing Project Committee 90.1 had voted to reduce the amount of glass permissible in the envelope of commercial buildings using the prescriptive path by a full 25 percent—from a maximum window-to-wall ratio of 40 percent to a maximum of 30 percent. It also voted for more restrictive U-factors and solar heat gain coefficient values and the addition of a new minimum for VT/SHGC (of 1.1) in ASHRAE 90.1's prescriptive path, even when there are no associated lighting controls. An appeals panel reversed these decisions in October—as this issue went to print—in response to appeals on behalf of Pilkington North America, Toledo, Ohio, and AGC Flat Glass North America, Alpharetta, Ga.; and one filed jointly by the Glass Association of North America, Topeka, Kan.; the Aluminum Extruders Council, Wauconda, Ill.; the Insulating Glass Manufacturers Alliance, Ottawa, Ontario; and Guardian Industries Corp., Auburn Hills, Mich.

As the basis for many state energy codes, the ASHRAE 90.1 standard could have significantly changed the green building landscape, populating it with new projects featuring noticeably less glass. While this didn't come to pass, the ASHRAE proposals serve as a reminder that the industry needs to continually educate building and code officials about the positive impact glass can have on the built environment.

The best thing the industry can do to make sure glass and glazing—and daylighting—remain a critical aspect of energy-efficient design is to be engaged, says Chris Dolan, director of commercial glass markets, Guardian Industries. "As major stakeholders, the glazing industry needs to be part of the process," he says.

Bill Yanek, executive vice president, GANA, agrees. "The glazing industry strongly supports ASHRAE's efforts to improve energy efficiency in commercial buildings, but all improvements need to be based on sound technical analysis," he said in a release. "The glazing industry also needs to be part of the process throughout."

That process is ongoing, with new building codes and energy regulations emerging on a regular basis. While the ASHRAE reversal relieves some pressure, there will always be groups arguing for less glazing, says Tom Culp, owner, Birch Point Consulting LLC, La Crosse, Wis.

"This victory is a testament to the unified and vigilant industry action over the better part of a year," says David Walker, vice president of association services for the National Glass Association, McLean, Va. "In as much the issue is likely to reappear in three years, our industry should remain vigilant." 

Jenni Chase is editorial director of Glass Magazine, e-glass weekly and Write her at

  • Code update

    At press time, the International Code Council had just wrapped up final action hearings for the 2012 International Energy Conservation Code in Charlotte, N.C., where the industry saw a number of victories in the commercial skylight arena, including approval of mandatory toplighting requirements in commercial applications greater than 10,000 square feet in area. "AAMA has been promoting the benefit of daylighting in reducing energy costs for several years," says Julie Ruth, code consultant for the American Architectural Manufacturers Association, Schaumburg, Ill. Those efforts included AAMA-sponsored studies that showed energy cost savings of up to 30 percent could be achieved by combining skylights with automatic lighting controls. The new code provisions will now require that combination in much of the country, she reports. In addition, the 2012 IECC will permit skylight area of a roof to be increased from 3 percent to 5 percent when automatic lighting controls are provided–another initiative supported by AAMA, she says.

    Building upon the recognition that daylighting can reduce energy costs, AAMA also was able to maintain the permitted window-to-wall ratio for use of the prescriptive table for commercial construction at 40 percent when automatic lighting controls are provided. A reduction of the WWR from 40 percent to 30 percent had initially been approved during the 2009 code development hearings, Ruth explains. In addition, AAMA was able to achieve clarification that the WWR limitation only applies to the vision area of the curtain-wall or storefront system and not to opaque spandrel panels.

    Look for a more detailed report on the 2012 ICC final action hearings in an upcoming issue of Glass Magazine.

    —John Swanson, editor and associate publisher, Window & Door