I have an humidity problem in my basement. In the summer it ranges between 70-100% (RH). I think it's because of an attached crawlspace (about 8x10, 4' high) that has appears to have no floor. I can't close it off because it's where the sewer entrance and the basement is the only access to the crawlspace. Any ideas about how to resolve this? Would something like laying down 3mil plastic in the space prevent the water from entering the air in the basement from the dirt floor? I thought about concrete but I'm not sure it'd be too doable in such a small space, and I don't know how to do a concrete floor from scratch.

We are planning to finish our basement - we have the flooring picked out, walls, ceiling etc. We would like to build a wet bar (the plumbing connections are already there) - Where can I find different plans / ideas to help us decide on building the bar?? Also, There is a crack in the foundation where the piping for the woodstove is? How do I proceed to repair once the cold and snow are gone?? Thanks!