I currently leave in Atlanta, Georgia and in a home that was built in 2001. The orginal owners did not have the basement finsihed and it is currently a dirt subfloor covered with plastic. The height is about 7'2" from dirt floor to bottom of joists. I was wondering if I could excavate some of the existing dirt out and then then install a think mil plastic, and then build a PT wood subfloor with joists above? This would give me a "project" to do and save on the cost of pouring a floor with concrete. Does or has anyone had any insight on this? Is it a good idea?