AAMA/IGMA Summer Conference Day 1: Report from the Emerging Technology Committee
By Patrick Flannery
The Insulating Glass Manufacturers Alliance Emerging Technologies Committee was chaired by David Cooper of Guardian. Co-chair Helen Sanders of Technoform was unable to attend. The committee was meeting at its Summer Conference in Victoria, held this year as a joint event with the American Architectural Manufacturers Association.
The committee got an update on the activities of its thermal stress task group from technical consultant, Bill Lingnell. He told the room that the huge task of establishing allowable thermal stress on insulating glass unit edges had entered the “red zone,” with 6,750 test runs out of 9,000 complete. Only tests on semi-rigid spacer remain to be done, pending more information on foam spacer characteristics from suppliers. The enormous number of tests became necessary due to the many variables the experiments have to control, including different spacer varieties, types of frames and edge bites. The hope is to generate a table that will describe the probabilities for failure under various thermal stress conditions, with perhaps one in 1,000 being an acceptable safety level.
Joanne McKinney of AMS reported on efforts to develop an accelerated ASTM E2190 test using their Rapid Assessment Chamber. The hope is reduce the testing time for humidity, pressure fluctuations and UV exposure from the present 15 weeks down to two or three weeks. The results continue to challenge the researchers as their test units sometimes seem immune to the abuse the RAC inflicts and sometimes fail almost immediately, and everything in between. Correlation with results from the old E2190 tests is also elusive. Now a cold cycle has been added to the parameters of the accelerated test, so temperature fluctuations from 140F to 20F will be included. Sensors in the RAC are delivering more information about what is happening to the IGUs during the test, which should be useful when manufacturers want to determine why their design passes or fails.
Cooper reported that several organizations continue to work on a vacuum insulating glass standard, but ISO has published one. So far, the standards only address themal performance – Lingnell pointed out that structural standards will be needed next.
Urmilla Sowell of NGA reported that the National Glass Association continues to work on a VIG standard for application and performance but publication is probably years away. Structural tests perform strangely on VIG and there are many different edge approaches to consider. The Insulating Glass Certification Council is wrestling with the question of how to certify various types of hybrid triple designs with a VIG unit incorporated.