First, I'd take a 2'x2' piece of plastic and tape it securely to the floor...maybe do this in several places. Leave it a couple of days to see if any or how much moisture is trapped underneath the plastic. Then, I'd evaluate my choices. Personally, if things stayed dry, I'd seriously consider an engineered hardwood product rather than solid wood (and probably still would once I had moisture controlled). There's a huge amount of it available in various price ranges and various thicknesses. I'd look for one that can be installed as a floating floor. Quite awhile ago, I was at a home show in LA. I asked a guy, after telling him I lived on the east coast and wasn't going to buy anything from them, what he would install, if he were going to install wood flooring. He said something from www.kahrs.com . He said the company he worked for did not sell that brand, but he had worked elsewhere, sold it, and found it to be topnotch stuff. They have a huge selection, but you may have to search for a dealer. They do not sell online, so you have to find a dealer. Both glue down, floating and nail down stuff, in lots of woods, finishes, thicknesses, and choices...all real wood surfaces. Adding a lot of thickness to the floor, if there are stairs getting to that level, may mean rebuilding your stairways since there are some strict requirements about consistency of the rise of each step.