We bought last year an apartment of the 1st floor. The building has garages and utility rooms right under our level and the two bedrooms face north. One of the bedrooms has actually an external wall also to the east. Insulation in the building is rather poor (80's built). Both bedrooms have wooden floor (the clicking type) made by previous owners. Under this wooden floor there is a plastic (a vapor barrier) and under it a concrete surface. The east-north bound room is suffering from condensation mold and after thorough investigation there is mold under the vapor barrier and on to the concrete surface. We plan to have the building insulated externally but until then I must do something to help the room.
I know how to clean it but how can I prevent it from appearing again? if I put a mold resistant paint of the concrete surface, will it be safe? it is a bedroom and we use it for sleeping as well as a home-office, I would hate to find the same problem next year.