35-40 year old concrete with moisture problems
We have a single story, 375,000 square foot facility built in stages between 1963-1970 in Southeast Fl. Most of the building is dock high and has a 4" slab with a vapor barrier. In the past few years we have had a problem in various areas, not contiguous, with mastic holding under VCT, carpet tiles with rubber backing, and gym rubber floor and mats. We even had some growth under VCT in one area. [/size] I have done RH tests-95-99% and calcium chloride tests- 14-19lbs. We have checked roof drains, GPR, the water is overhear and there are no obvious areas of water intrusion or leaks. Any thoughts?