I live in a 1930s house and one room in the house which has parquet flooring, is constantly covered in a grey, dusty fluff. Its only this one room and I have no idea where its coming from but every week there is a whole dustpan full of fluff and I am worried about it affecting the breathing of my child who spends most of his time in this room. I wonder if its a lining under the flooring or perhaps something like insulation in the walls that is leaking out. Does anyone else have this? I would be grateful for any help. Thanks.