We recently noticed a leak and found that it was coming from worn away sealant between the bath and the wall. I had a plumber come round, and he basically took off the tiles at the front of the bath (picture attached) and said it's all rotten underneath. The people we bought the house from had put the tiles on top of plywood (I think) and it had become wet, and basically needs to be redone. This plumber is now nowhere to be found - doesn't answer phone calls/messages, etc.
I have decided to fix this myself.
I'm looking for advise on how to do this. On top of this was one tile piece that I still have. The bit that remains is wood that has got wet and is now dry - very fragile and breaks apart in my hands.
My questions are
1. what do I replace this wood with, and where can I find it? Everything I have seen only fits in gaps 20mm wide. This is about 10cm!
2. Do I just use some silicone sealant to attach it from the wall to the bath and then stick the tile on top, or is it more complicated than that?
Probably can tell I'm not a regular DIYer, so please give me the most simple solution!
Thanks for your help