I went to get my inner tent which was in a plastic bag in one of the front under seat cupboards of my 2007 caravan, only to find that the floor under the plastic bag was wet, the rest of the contents and the cupboard was dry, the bag only took about a quarter of the cupboard area and was on the floor nearest the centre of the van. There are no water pipes in this cupboard, only ventilation holes. The inner tent had only been there for a month ( since our last holiday ) and was guaranteed put away dry. I think there was too much water for it to be condensation. Any other ideas please?