The major reason for leaking bathrooms is poor waterproofing prior to tiling. This is especially the case for older homes where waterproofing products weren't as good as they are nowadays. However, it can still be a problem for modern homes if the application was sloppy.;
, Try to find which bathroom appliance might be the source of wet patches or drips (shower, bath, toilet).


Turn on each appliance in turn, checking the drips or the wet space to see if it worsens with any particular appliance.






Leaving water overnight in a shower pan or bathtub can help you to find a leak if one of these appliances is the cause. If there are no leaks, eliminate the bath or shower from the search. Be aware - a hole as small as a pinhole can cause a massive leak beneath!






Check the pipe between the valve and the shower head.
 Usually there is ceiling space between the upstairs bathroom and the lower ceiling.


Cut a hole in the ceiling to enable you to undertake a visual inspection of the pipework to see if the pipes are leaking, or to see if there is direct leaking from under the tiles.
 If you find leaking pipes, get the plumber as soon as possible. Unless you're fully trained in plumbing, leave this one to the professionals to fix. Having a plumber do an inspection will also help you to know whether or not you need to go to the expense and trouble of lifting off all the tiles and waterproofing and re-laying them!
Check the waterproofing.
Run one fixture at a time.
Check the pipes.
Get a plumber.
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