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October  2004

IG Assurance

IGMA Summer Meeting Serves As Educational Venue

by Ellen Chilcoat

Understanding how insulating glass works and its various components is an important element for window manufacturers. From energy requirements to thermal stress, window manufacturers need to be aware of this component, as it is a major driver when it comes to overall fenestration performance.

One source from which window manufacturers can learn about insulating glass is the Insulating Glass Manufacturers Alliance (IGMA).

“Window manufacturers need a total understanding of how insulating glass works,” said Bill Lingnell, IGMA technical consultant. “The better they understand [insulating glass] the better they will be able to do their job.”

Gerard Lagos of Andersen Windows agreed it was important for window manufacturers to be involved.

“As manufacturers we see ourselves as specifiers, so it’s important to be involved with developing standards, so that our customers viewpoints are taken into consideration,” Lagos said. “It’s good [for window manufacturers] to be there [at IGMA meetings] and take part in the development of quality IG.”

Providing such news and information pertinent to the insulating glass industry, IGMA’s summer meeting took place August 5-8 at the Harbour Towers Hotel & Suites in Victoria, British Columbia. Nearly 100 participants took part in the meeting.

Learning from Others

From the various discussions, window manufacturers could learn about issues that involve IG. A number of technical presentations were offered that covered such topics.

Jeff Baker of WestLab led a presentation titled “Everything an NFRC simulator Would Like to Know About IG But Didn’t Learn from the Window Manufacturer.” Baker talked about the various requirements needed for NFRC reporting, such as glass thickness, spacer thickness, glazing types and other materials used in the window.

Though Baker, through his presentation, was targeting the IG manufacturer specifically, he said it is still important for window manufacturers to understand all the components that go into the sealed unit they buy.

“We want window manufacturers to understand the importance of good information on all the products they offer,” Baker said. “If they don’t [understand] and there’s a problem with the unit it could cost them even more financially in the long run.”

Discussing the recently published book, Window Systems for High-Performance Buildings, co-author John Carmody from the University of Minnesota was the next presenter. The book is designed to help professionals understand all of the options when it comes to window selection for commercial buildings. Carmody is also a co-author of Residential Windows: A Guide to New Technology & Energy Performance, which covers the various elements of residential window designs and performance.

How To Certify IG

With IGMA and the Insulating Glass Certification Council (IGCC) continuing to move forward with the certification harmonization (see related story on page XX), understanding how to become certified is an even more important element. A panel led by Marg Webb and Bill Lingnell of IGMA, John Kent of IGCC, David Bailey of Bodycote Materials Testing Canada Inc., Elie Alkhoury of Can-Best and Bob Davison of Intertek Testing, discussed the various steps, procedures and requirements for certifying IG.

“Certifying is an assurance to the end user,” said Webb

Lingnell provided an overview of the standards: ASTM E2188 is the standard test method for IG unit performance; ASTM E2189 is the standard test method for resisting fog in an IG; and ASTM E2190 is the standard specification for testing IG.

Other topics of certification covered included auditing, inspections and testing.

Safety Glazing

John Kent, who also serves as the administrator for the Safety Glazing Certification Council (SGCC), talked about safety glazing code requirements and labeling.

“An IG unit is the most important component of a window and safety glazing, when used in an IG, is an important component of that,” said Kent.

Kent began the presentation by giving a “who’s who” look at safety glazing and standards, from both the U.S. and Canadian standpoints. Test standards evaluate the performance characteristics of a product; building codes establish the requirements for use; and third-party agencies, which are voluntary (such as the SGCC), provide interpretation and implementation.

“Test standards [are necessary] because they help facilitate a seller of glass getting it to the buyer,” said Kent.

Kent also compared the differences in testing, codes, third-party agencies and labeling used in the United States and Canada.

Thermal Stress, Testing Standards

Sometimes, glass breaks and you (window manufacturers) don’t always know why. These “mysterious breaks” could be caused by thermal stress. Bill Lingnell led a presentation that looked at thermal stress design and considerations and the proposed ASTM standard for determining the resistance of single-glazed annealed architectural flat glass to thermal loadings.

IG Testing Standards

Jeff Haberer of Cardinal IG provided a comparison of the different IG testing standards: the old ASTM E773, E1887, E774; the old CAN 12.8; the new ASTM E2188, E2189 and E2190; in Europe (CEN), EN 1279 (parts 1-6) and ISO DIS 20492 (draft standard).

“The newly harmonized ASTM standard (E2190) is now recognized in both Canada and the United States as the testing protocol for insulating glass certification,” said Haberer. “For window manufacturers selling into Canada and the United States it will be beneficial to certify to E2190 and eliminate duplicate testing and certification. This will reduce cost and simplify compliance.”

Window manufacturers selling into Europe will soon have to provide products that have a CE mark, a certification protocol.

“This means the IG units in these windows will have to comply with EN1279. Failure to have the CE mark will mean that the windows will be stopped by customs officials and not allowed into the respective country,” said Haberer. “Loss of business or severe penalties for non-compliance will be experienced by companies that are not ready for the changes happening in Europe.”

Low-E Coatings

A panel discussion of low-E glass coatings also took place. Presentations were made by Bob Spindler of Cardinal IG and Chris Barry of Pilkington.

In his presentation, Spindler noted performance characteristics of both pyrolytic and sputter-coated low-E coatings, and talked about potential problems with low-E. Thermal stress breakage, for example, could occur if solar heat absorption is too high in annealed lites; sealant adhesion can also be an issue to both edge-deleted and non-edge deleted coatings. He also said high solar reflectance has the potential to create vinyl siding distortion.

Barry talked about how all low-E products are different. His presentation included a number of graphs that compared solar heat gain co-efficiencies to visible light transmittance to show various performance options with different low-E coatings and glass substrates.

Jim Fairman of Pando Technologies ended the conference with an update of the IG Durability Knowledge Base project. Conducted by Aspen Research and funded by the Department of Energy (DOE), the two-year project is looking to gain a qualitative understanding of the characteristics of IG durability, as well as tools for predicting IG durability. Those leading the program are currently waiting to hear if their application for additional development will be accepted by the DOE.

Want to Learn More?

If you were unable to attend the IGMA’s summer meeting, there will be future opportunities. The group will hold its annual meeting February 22-27, 2005 at the Fairmont Acapulco Princess in Acapulco, Mexico.


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