Just bought a second floor 5yrs old apartment. There is a smell in the bathroom - like a damp smell. Not a waste smell. A fully tiled bathroom, we have checked for leaks, there is no damp anywhere. The smell comes and goes! The apartments have had drainage problems and had a drain cleared last month. It's only in the bathroom. Seems all over, not in a specific spot. Its an internal bathroom, no windows. We replaced the extractor fan, but no difference. Any ideas would be appreciated!!