Picture below is of an exterior wall where it connects to the ceiling (ceiling is acoustical texture; wall is flat). Water strip about 2.5 inches wide runs the whole length of the ceiling after it rains, right under the roof line and gutters.

Called the gutter guys; they said the overhang of the roof is directly over the gutter so the water should be flowing into the gutter (see drawing below). Checked the attic and didn't see any water. But somehow the water is getting out. Their next step is to put a piece of flat metal under the roof over the gutter to be sure the water can't get closer to the house.

I think it's got to be something with the gutter but can't figure it out. Am I missing something?

drawing of roof/gutter

Ceiling water mark

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    We'd have to see the gutter. We're guessing blindly otherwise.
    – isherwood
    Oct 27, 2017 at 13:12
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    If you've ever poured water out of a jar and had it hug the edge of the jar and not follow gravity like you intended, that's the Coandā Effect, named after a guy named Henri Coandā who invented it. This effect gives airplanes extra lift at low speeds and also makes you spend an hour cleaning paint off the floor. It may be making the water miss the gutter. I hate that guy so much. Help me invent a time machine so we can go back and kill him berore he invents it! Oct 27, 2017 at 14:43
  • @Harper ?? And Isaac Newton "invented" gravity. Explaining and naming a law of physics is NOT Inventing it.
    – Alaska Man
    Oct 27, 2017 at 18:06

1 Answer 1


Do you have drip edge under the shingles, and flashing under that on your facia boards? This need to be in place before gutter is installed, otherwise water can be leaking from the gutter side closest to the house.

  • Upvoted: I think you're onto something here. I'm going to run this by the gutter repairman. Still open to other answers if anyone has any other ideas. Will circle up with an update once the repairman comes by.
    – chowwy
    Oct 27, 2017 at 15:59

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