I purchased a lot with a carport, which I filled it in, put a floor over just gravel sitting on 4x4 treated wood. The roof only slants from 8' front to 7' in the back. Overall size of the building is 20'x20'. The soil is basically sand. The problem is the 7' wall "wicks" up moisture into the walls as since there is no foundation - only the 4x4's. I have tried putting plastic on the wall and into the ground outside, but it continues to wick. Would like to put a foundation under the building, but I'm in my 70's and a woman, so I would like to keep the cost at a minimum. Will try to get pictures to better explain. Any suggestions would be appreciated. Thanks