Hi,
First post on here! Sorry if I'm about to ask a question that has already been answered. I couldn't find anything in the search index.
So... the sealant at the bottom of the wall where it meets the bathtub had gone mouldy, specifically behind the bath taps. I planned to just remove it and re-caulk with fresh sealant, but once I had removed the mouldy sealant I discovered that some of the mould had affected the bottom of the wall tile as well.
There are a handful of spare tiles from when the bathroom was fitted by the previous owners, so I thought to myself... No problem, I'll just remove the affected tile and (provided there was no further mould issue... which thankfully there isn't), then I would scrape off any hardened tile adhesive, clean it up, fit a new tile with fresh adhesive, re-grout... job done.
However as I began chiselling away the old tile, parts of the backing board started to come away with it, exposing the brickwork. I had already started by this point and the tile was obviously damaged, so I carried on until the whole tile had gone to see what I was left with. Most of the backing board has come away with the tile. A few bits remain, which appear to be solid.
My question now is... can this be rectified? I presume the backing is a waterproof cement board, but I don't know for sure. Hopefully the photos may help? I don't know if this can be 'patched' or replaced in any way, or if it can be filled or sealed with something, or if there's another solution? Obviously I need 2 things: 1) it to be waterproof, 2) to give me an adequate surface to apply the new tile adhesive. My fear is that the only actual solution is to bring the whole wall down and have it re-plastered and re-tiled... which would be a big and costly job! But hopefully I don't need to be as drastic...
I've attached a couple of photos.
Thank you for any help or advice!