I have just discovered that my shower has slowly been leaking through the grout in the tiles and then behind the plaster in my bathroom. It looks like it has been happening for sometime and is now showing signs behind the plaster downstairs under the bathroom.
I have removed some of the tiles and with them has come much of the surface plaster.
The house is about 200 years old and therefore has no cavity walls and is built of old stones, the wall behind the plaster isn't the old stones but looks like render.
I will remove all of the damp surface plaster and let everything dry out but do I need to replaster over, what looks like, the render or can I just tile over the top? Do I need to apply a sealant before re-tiling and how long should I give everything to dry out before re-tiling?
Any help that anyone could give would be very much appreciated! Thank you.