FFS, stupid concealed shower looks like it's been leaking. What do we do?

[CrapBag]

We have a shower room downstairs with a concealed shower (what idiot invented those!). It was put in by previous owner, we have been here 6 months.

We are in the process of having a new kitchen which is the other side of the shower room. When the breakfast bar was removed from the wall, the fitter pointed out a small black patch he thinks is damp, he said the floor didn't feel right underneath and there is a built in oven in the wall next to this area and when some panels in the wall were removed because the air vent wasn't adequate and there is a load of black in there, it is the other side of the shower cubicle but not the wall where the actual shower is attached. Could the crap air vent have caused that black?

What do we do? I don't see how we can find out for definite without either taking the sodding tiles off the wall and opening the wall from the shower side or opening up the wall on the kitchen side and even then the places where there is a potential problem are wide apart and in about 3 different places so wouldn't know where to look.

cut open the plasterboard on the kitchen side and have a look. You can open it directly behind the mixer, or lower. It is fairly easy to put in a new piece of plasterboard. You want a hole that reaches from one stud to the next, and preferably has a noggin top and bottom, so big enough to work through.

Treat any wood with wood preserver after it has dried out. If you need to rebuild the wall on the shower side, use tile backerboard which is cement based and impervious to water.

Next time, get a surface-mounted shower, with chrome or stainless pipes running down from the ceiling. They look perfectly acceptable.

Thanks for the advice. Will get DH to open up the wall. Don't want to add more to our kitchen bill at the moment by asking them to do it as they have found a couple of problems and I have got them to fix some of the shit job done by the plumber we got to do the upstairs bathroom.

When we did the upstairs bathroom a concealed shower unit was included with the set we bought but I purposely didn't conceal it for this very reason and it looks absolutely fine as it is.