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Unsure if crack/damp patch on bathroom ceiling is due to a leak or moisture?

Hi there

Our bathroom is in a flat - it has no windows, but it does have an extractor fan above the shower in the corner. We renovated it around 2 years ago, when the bathroom was painted fresh. The ceiling is like a drywall.

In the last month or so, we noticed some cracks and damp looking stains appearing on the ceiling above the shower.

We are not sure if this is due to inadequate ventilation so its absorbing moisture, or if there may be a leak above the ceiling that we cant see.

Im not sure if its best to get a plumber out to check?

Thanks a lot for any advice!

4 Answers from MyBuilder Plumbers

Best Answer

I’d say If nothing is above the ceiling ie water feeds then it’s due to poor ventilation


Answered 10th Jun 2020

Hello,If this was a leak from above, water would physically be dripping from that area, this I think is a lack of ventilation issue, which you can resolve by doing the following, wash down the ceiling with a anti mould spray, once clean and dry, Fill the cracks with wall filler, allow to dry then paint the ceiling with an (Anti mould bathroom paint) 2 coats, then whenever you shower or bath, make sure when You leave the bathroom (always leave the door wide open) to air the room once you’re finished, and try and leave at least one window ajar in any adjoining room to improve circulation and that will solve the Problem.


Answered 10th Jun 2020

A problem like this is difficult to assess without seeing it first hand. You can either have a look in the loft if there is a water pipe above the bathroom, this will help locate the likely cause. If there aren't any pipes have a look at the roof to see if there are any water marks that could indicate a leak from above dripping onto the ceiling and then seeping through.
If you don't find any of the above as a source then it could be damp caused by insufficient ventilation. If still unsure you should get a professional out to have a look. Hope you get it sorted.


Answered 23rd Jun 2020

Or if a top floor flat it could be Condensation from a cold Water storage tank or cold main that’s not lagged or it could even be a broken roof tile So worth popping your head in the loft For a look


Answered 28th Jun 2020

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