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We had a leak in our upstairs bathroom, about 2 weeks after we had a new ceiling put up and painted in the room below. It wasn't a major leak, but it caused quite a wide line to show up on the ceiling.

I've painted over the line 3 times now, but it just keeps reappearing, is there anything I can do to stop the water mark from showing up?

Jaymz
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5 Answers5

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Stains will usually come right through a new coat of paint.

Did you prime it first? In my experience I've found that a good oil (or even better, shellac) based primer works best for keeping stains from bleeding through the paint.

Eric Petroelje
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Leave it to dry thoroughly. This might take several weeks, I'm afraid.

Once dry, try an exterior-grade primer before two or three more coats of paint.

Jeremy McGee
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  • It's been a couple of months now since that happened, so it's definitely dry. I didn't use a primer though, so I'll give that a shot, thanks. – Jaymz Jul 21 '10 at 19:42
  • +1 - using primer is the key to deal with moisture transmission - http://diy.stackexchange.com/questions/2797/how-good-do-i-need-to-make-my-primer-coat/2820#2820 – sharptooth Dec 21 '10 at 06:23
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Use the expensive kilz primer then repaint. The oilbase spraypaint primer is also a good idea but don't over spray.

Jesse D
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I have had good luck with the Kilz brand of primer, but I'm sure any quality stain hiding primer would work well.

SchwartzE
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We had massive leaks through our ceiling during a renovation. The ceiling had to be sealed first. Our painter mixed in 4 litres of sealant with the undercoat (again, massive leaks). Even this did not totally help - some stains still came through.

As the new stains came through, we sprayed them with a can version of the sealant (White King Stain Stop Sealer) then repainted the stains. That seems to have done it.

dave
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