Waterproofing shower

There are a number of reasons this could be happening, I carry out insurance work and have seen every leak possible with showers! Seals are a common cause if they are not maintained, once you have a seal gone then water can start getting to the floor/platform underneath and after a short time this will cause more movement and the leak will get worse! It could be you have a leak from the waste or a feed pipe but I would advise to track the problem as fast as poss to minimise internal damage elsewhere. Not the hardest of jobs and if you can’t do it yourself then maybe your insurance company could help, most will carry out a “trace and access” visit and find the leak!

Yes you definitely have a leak. However this is happening for any number of reasons. It could be and most likely is straight forward to resolve. You need a professional to resolve the issue.