Help. I have black spots of mould appearing on the wall under my bedroom bay window. The wall is decorated with blown vynyl and emulsion and the paper is beginning to lift. The right hand side of the bay is virtually clear and the worst spot is the left hand side.
These black spots are also on the paster underneath and and the windows which are upvc double glazed.
My husband has sealed under the window sill and he tells me there are no tiles etc missing on the outside.
I do have floor length curtains at the window but the top small window is left open all day although not at night as we live on a main road.
I do tend to have washing on the radiator sometimes so could it be caused by condensation?
How do I get rid of it?
How do I stop it reoccurring?