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April  2004

Information, Education, Socialization
IG Industry Gathers to Debate and Discuss Issues
 During Annual Meeting


by Ellen Giard Chilcoat

Remembering names, places, dates and facts is all about association. That’s how Bob Gray, The Backwards Memory Guy (yuG yromeM sdrawkcaB ehT), was able to memorize the capital, square footage and population of every city in the almanac. He’s also in the “Guinness Book of Records” as the only human who can speak and write backwards phonetically. Gray served as the keynote speaker for the Insulating Glass Manufacturers Alliance (IGMA) annual meeting, which took place February 24-29 at the Radisson Parkway Resort in Kissimmee, Fla. Committee meetings, informative speakers, a luau and other social activities were on the agenda. Approximately 140 people attended the event.

Making News 
The technical working groups met on the afternoon of February 25 to discuss a number of topics. The glazing guidelines committee, chaired by Tim Harris and Ken Shelbourn, both of TruSeal Technologies; gas permeability committee, chaired by Bruce Virnelson of PRC DeSoto; and Gasglass best practices committee, chaired by its U.S. distributor Randi Ernst of FDR Design, all met. A newly-formed visual obstruction committee, chaired by Bill Lingnell, IGMA technical consultant, met for the first time.

The glazing guidelines working group’s efforts are focused on harmonizing the IGMAC and SIGMA glazing guidelines into one document. During the meeting, final text revisions were reviewed and diagrams were selected for inclusion. Publication of the harmonized document is expected in August.

The gas permeability working group is overseeing and administering a gas permeability research project. The project has been divided into the following five phases:

1. Evaluate the permeability of sheet materials;
2. Evaluate the gas permeability of edge-seal assemblies;
3. Evaluate the gas permeability of sealant systems in a strained condition, both physically and environmentally;
4. Develop a mathematical model to predict gas loss rate from an IGU; and
5. Develop an approved test method for measuring the gas loss rate from a sealed IGU.

Requests for proposals (RFPs) to conduct the testing have been distributed to approved research laboratories; two had been submitted and were reviewed during the meeting. Various members of the group voiced concerns about the costs of the proposals. The working group planned to bring the matter to the board of directors and discuss the possibility of partnering or sharing the work with other organizations.

Keeping the project on an industry level, however, is important to many involved.

“Overall durability [not just gas retention] is a huge issue facing our industry,” said Ernst. “We can’t keep our heads in the sand. If we don’t do something, we’ll have something given to us by someone else.”

Ernst also lead the Gasglass best practices working group. Actions for the working group include:

• Developing standardized calibrations for the Gasglass device;
• Developing a standard operating procedure for the Gasglass device;
• Developing IGMA guidelines using the ASTM standard template; and
• Round robin testing.

“What’s probably going to be key is making sure we follow ASTM procedures,” said Ernst. The group is in the beginning stages of round robin testing. Ten to 20 blind, sealed units will be sent by IGMA to Gasglass owners willing to participate. The goal of the round robin testing is to see how consistent readings are among the user population.

The visual obstruction working group met for the first time and discussed what its scope and objectives would be. The group is planning to work toward determining criteria for observing visual obstruction in sealed IGUs. A future objective is to put the criteria into a guideline/paper form and continue to review within the group.

“It’s the type of thing we’ve been asked to do as an organization … [to develop] a standard/benchmark,” said Lingnell.

Making Progress
Some big news for IGMA, and the North American IG industry, came in the announcement that the Harmonized Insulating Glass Standard (commonly called HIGS) has been accepted by the National Building Code of Canada (NBCC). The 2005 National Building Code will reference ASTM E 2190. 

Ray Wakefield of Trulite and Marg Webb, IGMA executive director, were instrumental in seeing the standard accepted by the NBCC.

“It was a major achievement for both the industry and IGMA to have successfully harmonized the standard,” said Wakefield. “It was nine years of hard work,” he added.

The formation of a working group for thermal stress in insulating glass was discussed at the technical services committee. While many agreed that thermal stress was one of the most misunderstood problems in the industry, they were not certain that their group was the appropriate forum for the matter. Currently, ASTM has a working group, focusing on monolithic glass, which has a draft standard on thermal stress; some are hopeful that IG will be next.
“IGMA is not the place for a design standard,” said one member. “ASTM is.”

Technical Presentations
A number of presentations also took place.

One presentation focused on spacer bar design and window performance. Hakim Elmahdy of the National Research Council (NRC) [of Canada] had been involved with a research project that looked at how certain spacer bars can improve window performance; he spoke about the project during the session. (Editor’s Note: The following is a brief summary of the testing conducted by Hakim Elmahdy and NRC. The entire research article, CTU-58, can be downloaded at www.nrc.ca/irc. Go to Publications, Construction Technology Update #58.)

The study looked at ten different spacer bars (nine with warm-edge technology and one conventional) in IGUs, first without window frames and then with frames of various materials (redwood, vinyl, thermally-broken aluminum and foam-filled fiberglass). 

According to Elmahdy, the testing of the units without frames found that the unit made of foam with desiccant and sealant was the best in terms of condensation reduction, as it had the highest glass surface temperature at the edge of glass region. Results also showed that the unit with the conventional metal spacer had the lowest glass surface temperature in the edge of glass region.

Upon testing the framed units, Elmahdy reported that the combination of the foam-filled fiberglass and the insulated spacer bar provided the warmest glass-surface temperature at the 10-mm plane, which reduced the potential for condensation. The combination of the thermally-broken aluminum and the hybrid spacer produced the lowest temperature.

The study also looked at R-value. According to results, wood has a high thermal resistance, so those specimens tested best in terms of overall R-value.

Energy Matters
Jeff Baker from WestLab provided an overview of the Canadian and U.S. Energy Star® programs for fenestration products. He explained that to be Energy Star compliant in the United States, products are required to be NFRC-certified. Once certified, manufacturers apply their products for inclusion in the Energy Star program. In Canada, products must be either CSA or NFRC certified. Once certified, manufacturers apply for their products to be in the program. 

Educational Information
Several others also made presentations. The following topics were discussed:

Dade County (hurricane code) update, Jeff Granato, DuPont; DOE update, Jim Fairman, Pando Technologies; causes of glass breakage, Chris Barry, Pilkington NA; fogging capabilities of different materials, Bob Spindler, Cardinal Glass Industries; thermal stress behavior of thin glass with edge chips, W. Lynn Beason, Ph.D, P.E.; insulating glass moisture and damage control systems, John Hennessy, Crystal Clear Window Works; and the SashLite technology by Mai Misra from H.B. Fuller.

Looking Ahead
The 2005 annual meeting will likely take place in Acapulco, Mexico. 

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