Damp and mould

Just remembered that in December when we visited the new surgery the walls of the waiting room were full of dampness and mould. Especially under the small window, and on the side of the toilet door, but elsewhere too. I just wonder if there is in UK something, what we could use for treating those walls to get rid of mould and damp. Perhaps in the summer. That would be more than useful. The good news is that the main rooms are fine, there is no dampness at all.