As the containers are a "go to sea" for original use I hardly think humidity would damage whats inside? They are for sale/rent all over the USA as are old tractor hwy trailers. My local school uses 2 containers for dry storage. I really dont get them as a support for a bldg? I can see having either or both but not built together unless they were a freebie, which is unlikely. They will cost more than the materials to build the walls for a pole bldg..