Active job

Waterproofing of wall shared with wardrobe

We have a suspicion that the wall shared with our wardrobe in our ensuite isn't waterproofed/watertight. We're having issues with dampness and mould in the wardrobe. We've recently had our roof replaced so hoping this helps but I'd also like to have this wall waterproofed just to be sure! We have a baby on the way and she will be in our room the first six months so would like to make sure the room isn't damp. This wall has the vanity and a mirror on it and bath is also connected to it. Dependent on cost of this work, I'm also considering whether to do further remodel of the bathroom.