FGIA updates report on preventing glass breakage in insulating glass (IG) units
Posted on January 26th, 2026

“Glass breakage occurs when the glass stress from an applied load exceeds the glass strength,” said Amy Becker, FGIA Glass Products Specialist, and staff liaison for the FGIA Preventing Glass Breakage Task Group. “Glass strength varies greatly as a result of small scratches or other surface damage which act as stress concentrators.”
Glass is weakened by static fatigue that allows a very small and invisible crack, which could resist a short duration load, to slowly grow when the same load is continuously applied. Snow loads on skylights, book and ornament loads on glass shelves or water pressure in an aquarium are all examples of long duration loads. Visible fractures can appear hours, days or even months after the load is first applied.
IGMA TR-3401-25, as well as other documents available from FGIA, may be purchased from the online store at the discounted member rate of US$18 or the nonmember price of US$36.
For more information about FGIA and its activities, visit FGIAonline.org.
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