Posted this in home decoration but had no replies there so thought I'd try here instead.
I noticed a small section of our bedroom wall had become covered with black mould as our bathroom fan was broken and so there was a lot of moisture. I treated the mould with a vinegar scrub and then with a chemical spray which seems to have removed most of it. However the wallpaper is stained now. I don't want to remove the wallpaper if possible as the house is very old and the wall behind is likely to be in bad condition. Is it an option to wallpaper over the existing wallpaper? I also bought some damp paint. Should I put a coat of this on first do you think? Thanks.