I have a kitchen unit with cupboards and drawers which is fixed to an external wall, and the kitchen is in a semi-basement, so the top of the unit is just below the pavement outside. (It’s at the end of a terrace.) Not very surprisingly there is damp behind the unit, which is causing mould in the cupboards and drawers. Either side of the unit there are tiles, and no damp or mould is evident there; behind the unit is plastered brick. I am wondering what to do about this damp problem. One possibility might be to remove the unit, hack away plaster, instal a damp-proof membrane or apply a damp-proof paint (which?), then replaster. I wonder if it might also be worth fixing with plugs going into brick a rigid sheet of something like pvc (to prevent the membrane or paint possibly being loosened eventually by damp) before reinstating the unit, but I’m not sure how worthwhile this would be. I’m also not sure if it’s worth removing and replacing plaster rather than just applying the membrane or paint to the existing plaster. Obviously a limited treatment like this would leave damp elsewhere behind the tiles, but it’s the kitchen unit which is the urgent problem, and I’m certainly not going to remove all the tiles. Any ideas?