HELP; Building is up and getting ready to dig pool. Sounds crazy, but this way was able to work thru winter months. Building is 36'x60' with 18'x44'x4' pool. Will have bathroom, shower and mechanical room inside. South and East side are all 5'x6' windows and French doors. Ceiling will be stained and sealed car siding. Please see pictures. Was told by pool builder that I needed a Desert Air System to control humidity. It is sounding very intensive and extremely expensive. I am an amputee and wanted a pool to swim and work out in year around located in the Midwest. What have others done.