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ceiling drywall bowing up

user-1112892055 | Posted in General Questions on

what could be causing the drywall in  a small house with an ERV that is very tight to bow up between the ceiling joists ?

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Replies

  1. Expert Member
    Michael Maines | | #1

    Likely too much moisture on the back side.

    1. user-1112892055 | | #2

      Spot on. I discovered the dryer vent was ducted into a very tight attic. You rock! Thank you 🙏🏼

      1. Expert Member
        MALCOLM TAYLOR | | #3

        coz24,

        Great the solution was so simple!

      2. Expert Member
        Michael Maines | | #5

        You're welcome! I like a challenge but in this case I'm glad the problem was so easily solved.

        1. user-1112892055 | | #6

          thanks so much Michael, so rock always bows towards the wet side ?

          1. Expert Member
            Michael Maines | | #7

            Porous building materials always bow toward the wetter side; when they absorb moisture, they expand. It's likely the paper facing, not the gypsum core that expands.

            You often see the same effect it in exterior wood such as on decks, where the top dries out from the sun while the bottom side stays cool and damp, leading to cupped boards.

  2. user-1112892055 | | #4

    Grateful for this forum!

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