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Why are my Willmar Windows (Jeld-Wen) sealed glass units repeatedly failing?

Jane Gray | Posted in General Questions on

Subject: Willmar Windows Jeld-Wen Ontario Canada

In 1997 we purchased 78 top of the line windows and doors from Willmar Windows, a division of Jeld-Wen. These were “R+10 with Heat Mirror, Metal Clad Wood” windows and doors.

Since the first year there has been a steady rate of seal failures. In 2004 Willmar decided to replace all of the glass units. In 2007 Willmar finally accomplished this.

They were replaced with glass units called Tripane T2SA with “Triple Solar Shield, 2x Low E and Argon”. Since 2007 we have had 12 seal failures in these units.

We are about to contact the company about these seal failures. In 2007 Willmar gave us a 5 year limited warranty on the Tripane T2SA glass. At the time, this glass was being manufactured with a twenty year warranty.

The framed windows are 3’x5′, 3’x3,’ 3’x3.5′, and the doors are 3’x8′, 3’x 6’8″.

All exposures are effected with the southern exposure having the highest
failure rate. The windows are awning style, with opening and fixed both failing. We have no curtains, no stained glass, no baseballs, no ice forming under the glass units, and no reason we can think of for what is causing this failure rate.

Since your magazine has a wealth of knowledge, I thought I would do some independent research and I am asking for your thoughts. Is there a known cause and remedy for this sad and foggy situation?

Thank you for your help,

Jane Gray

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  1. GBA Editor
    Martin Holladay | | #1

    It sounds like the rate of glazing seal failure in your windows is unusually high.

    The only protection that a homeowner has against the high cost of replacing glazing with seal failures is your window warranty. Reputable window companies stand behind their products and correct this type of problem; less reputable companies have weaker warranties. I'm not very impressed by Willmar's offer of a 5 year limited warranty.

    For more information on glazing seal failure, see this document from Pella.

    For technical information on the history of these problems and efforts to reduce the rate of glazing seal failure, see these two documents:

    Insulating Glass Durability

    Insulating Glass Technical Manual

  2. [email protected] | | #2

    Good morning Jane,

    Your experience with the original Heat Mirror IG units isn't unique unfortunately.

    Heat Mirror IGU's include a layer (or layers) of LowE coated thin, flexible, plastic between the two glass lites. This layer of LowE coated plastic results in triple pane performance with less weight and depth than a standard triple pane window.

    Adding several layers of the LowE coated plastic results in quadruple, and greater, energy performance numbers. The downside is that everytime you add an additional layer of plastic you increase the odds of seal failure.

    Southwall Technologies, the originator of Heat Mirror, claimed that the failures were due to incorrect manufacturing by the window companies - the claims and counterclaims resulted in a number of lawsuits with the result that while a number of major manufactuers once offered the Heat Mirror option, but because of widespread failures they no longer do so.

    Looking at the assorted Willmar-related websites didn't offer any information on what "Tripane T2SA" actually is. I did see that Willmar is currently manufacturing IGU's using the Superspacer system but not much more.

    I am also surprised that they only offered a five year warranty when they changed out the IGU's.

    Could you possibly describe the spacer that is between the lites in your current windows - does it look metal or does it look plastic? What color is it? Does it have little pin holes in it?

  3. Jane Gray | | #3


    The spacer in the Tripane T2SA looks like a dark grey or black plastic. They are Solar Shield.
    The glass unit was made by Jeld-Wen in September 2007 and some were made in 2008. There are no pin holes that I can see.

    Thank you,
    Jane Gray

  4. [email protected] | | #4


    It does sound like that could be superspacer which would fit what I found on line.

    You need to contact Willmar and let them explain what is happening with those IGU's. As Martin said, that is unusually high number of failures....I would call it phenomenally high for an IG using modern materials and manufacturing techniques.

  5. user-1135248 | | #5

    My first thought reading this is that Jeld-Wen is the typical
    "builder grade" stuff we find at HD and the other big-box places...


  6. Jane Gray | | #6


    The Tripane T2SA window units from the Willmar Insulating Glass Guide printed 11/2002 says "Tripanes manufactured by Willmar Windows consist of 3 panes of glass separated by two warm edge spacers, creating two nominal 1/2" (12mm) sealed spaces filled with air or argon.

    Thank you.

  7. CAL_PRICE | | #7

    Hi Ms. Gray, just wondering if you could provide us with an update as to how all of this ended up for you. I have a house with many Heat Mirror failures as well, and my initial contact with Willmar (now Jeld-Wen) was not encouraging.

    Thank you.

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