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Community and Q&A

Inline Windows shear blocks

user-6603947 | Posted in Green Products and Materials on

I am strongly considering Inline Windows for our home in Lincoln, NE (zone 5). The Inline rep informed me that the shear blocks (see attached JPG) Inline uses to mechanically secure their frames are made of PVC.

Wouldn’t this shear block introduce a potential point of failure in the window? Since the shear block is constructed from PVC, it will expand and contract at a much higher rate than the fiberglass frame. I’m thinking this could potentially lead to leaking corners as these shear blocks experience multiple heating/cooling seasons each year. Using PVC in this mechanical joint seems like it could greatly diminish the value of fiberglass frames.

I asked the Inline rep about this and an awaiting a response, but I was curious what others’ opinions are on this. Anyone have firsthand experience with these windows?

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  1. GBA Editor
    Martin Holladay | | #1

    I imagine that the engineers who designed the windows have considered thermal expansion and contraction, and that the window frame is able to handle typical temperature swings.

    If I were you, I would ask Inline about their warranty. Otherwise, I wouldn't worry about this issue.

    I've bought Inline windows in the past, and none of the windows I bought suffered corner failures.

  2. user-6603947 | | #2

    The Inline rep responded and said she was mistaken; Inline shear block are constructed of polyester plastic, not PVC. Per Inline, polyester plastic is more durable and stable throughout the temperature gradient. I don't know anything about polyester plastic, so I would have to do some research to confirm or refute this.

  3. user-6603947 | | #3

    Anyone have any input on the Inline warranty? It used to be lifetime, but it looks like they changed it a few years ago. Now the frames are covered for 20 years, but the hardware only has a 5-year warranty and the IGU is only covered for 10. Seems a bit on the short side and was curious if anyone has input on the reason for the change or if it is a cause for concern.

    Ideally, I just want a window where I never have to use the warranty.

  4. ethant | | #4

    Derrick... did you go with the Inline windows? If so, have you been happy with them?

  5. Stockwell | | #5

    Derrick--have you looked at Enerlux? Their plant is there in Crete, right down the road from you. They make some really high quality fiberglass windows.

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