I'm new to these forums so I hope someone can provide some advice!

I rent a house with my partner and lately whenever we shower in our upstairs bathroom (it's a bath/shower), we get streams of water running down our living room wall downstairs. The water stops when we stop showering - I've not tested yet to see if it still causes the leakage when we only use the bath or when the shower is running with noone in it.

There is a bit of back story to this: we had the bath re-tiled and re-sealed a little over a year ago because water was leaking from the corner of the bath out onto the shelf behind the toilet. Since then Iíve been trying to ensure that the seal around the bath etc stays dry but with having no windows and what I fear is a rather ineffective extractor fan in the bathroom, mold has developed regardless, which obviously makes us look bad to our landlady who will be the one who has to sort this out again. Weíve also had a mass water runnage down the entire length of the living room wall in the past caused by a faulty ballcock in the toilet which made the toilet tank overflow Ė that problem reared its ugly head again when the shower started causing leaks this time, although I noticed the warning signs and turned the water off before any more water damage could occur this time. This has now been fixed, and our landlord was hoping this would prove to have been the cause of the current leaking, but alas it seems not. Incidentally, when we were only turning the water on when necessary and at the minimum pressure to shower quickly etc while waiting for the ballcock to be replaced, the water didnít run down the wall when showering.

So! Could the mold be causing the leaks? Could the fact that the new tiles/sealant was put over the old be to blame? Can just not having enough dry airflow in a room be enough to cause black mold to form? The really odd thing that may give some plumber out there an Ďeurekaí moment is that at first the water was only running down the wall starting at the dado-rail level (about half way down the wall). Now itís running from the ceiling down the wall as well, and Iím wondering if this leak is separate from the leak at dado-rail level although it occupies the same half a metre wide section of the wall.

Sorry for the really long post Ė just trying to be as informative as possible! Any help or advice appreciated! Just want to know whatís going on so at least one party has some idea of what actually needs to be done!