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Marvin window Issues

BPortnoy1 | Posted in General Questions on

Hello. My Marvin ultimate windows are 19 months old. I opened a few windows that I’ve never opened and found that the corners  are completely separated. They also appear to be PVC which I was not aware is a component in the Marvin ultimate casement windows. ( unless pvc looks like fiberglass?) I understand there’s a possibility of this being due due to poor window flashing but this seems excessive. I reached out to Marvin and have not heard back yet, but would love to hear if you’ve ever seen this before and if anyone can explain what is going on. At least 4 windows are this way so far. Thank you

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  1. Expert Member
    Michael Maines | | #1

    Thanks for including the house fly for scale ;-)

    I haven't seen that happen with Marvins or any other window. Fiberglass does look a lot like PVC; it's just resin with reinforcing fibers. For the frame to pull apart like that, I wonder if the installers screwed through the jambs into the framing without adequate shims in place.

    1. BPortnoy1 | | #2

      It’s def a possibility. I guess I’ll know when I remove it. There are at least 4 that look this way.

  2. nynick | | #3

    Sounds like an installation problem to me.

  3. Expert Member
    ARMANDO COBO | | #4

    I don't specify Marvin windows, EVER! I believe the windows are great, but the flanges around some of their windows are cut out at the corners to facilitate shipping. The result is that they send some foamy corner gaskets with a sticky back to be glued in place, but half of the time those gaskets get lost, forgotten to be installed or put in place on dirty flange and/or sheathing, therefore, the chance for moisture problems increases a lot.

    1. BPortnoy1 | | #5

      Oh wow. I know exactly what you’re talking about. It leaves gaps in the corners.

    2. BPortnoy1 | | #6

      Where did you find those photos? I want to reinstall the windows properly and the Marvin guide that came with windows is very vague. Would love pics to show someone!

    3. Expert Member
      ARMANDO COBO | | #7

      Google... 🤠

    4. Expert Member
      Michael Maines | | #9

      Armando, do you rely on flanges for watertightness? I don't know of any manufacturers who suggest that's a good idea, unless perhaps they are fully integral the way low-end Andersons are. I always tape over the flanges onto the side of the frame extension.

    5. Expert Member
      ARMANDO COBO | | #10

      No Michael, I don't rely on flanges for watertightness or air-seal, but I'm realistic with the labor pool we have in Southern states. A continuous welded flanged makes it EASIER to seal, tape and waterproof windows.
      A good half of the homes I design, my clients have the windows installed by the window retailer with crews of experienced installers. The other half, windows are installed by framers who do not read, or even look, the window installation details on all my plans.
      I'm just trying to be proactive and minimize costly mistakes down the road for my clients.

  4. steve41 | | #8

    BPortnoy1- Are you sure that those are Marvin Ultimate windows? I believe that the Ultimate series has an aluminum clad exterior, or at least the ones that I just installed did. If fiberglass, perhaps they are from the Elevate or Essential line. This would be key to ensuring that you use the correct installation instructions. They are all on Marvin's site:

    As a side note: I'm in full agreement with Armando (post #4) regarding the corner gaskets on the "fold out" flange windows. I was less than impressed with these gaskets and used my own made from Siga tape.

    I also agree with the others: it's likely an installation problem on your windows.

    Best of luck.

    1. BPortnoy1 | | #11

      Thank you. My invoice says ultimate. I was surprised also. It’s says custom jams so perhaps custom they did was fiberglass? I haven’t had much luck talking to anyone from Marvin. I’ve reached out several times.

      1. steve41 | | #12

        If you have not already- perhaps try working with the installers or the Marvin Dealer, rather than Marvin directly.

        My local Marvin dealer was great to work with, very responsive and customer focused. My situation required replacement of several units.

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