Just bought a 100 year old home with hardwood floors throughout. For a 100 year old home the floors are fairly level and in pretty good shape. We could sand and refinish the floors and they would look good but here are my concerns. The flooring was laid directly over the floor joists with no other subflooring. There are some gaps in the floor where you can actually see the basement light coming up from below. The basement is damp, drafty and full of critters. Just refinishing the floors will still leave the gaps and unwanted ventilation coming from the basement.

I was wondering if new hardwood could be installed directly over the existing floor. If not the alternative would be to pry up the old flooring, install a subfloor and then install the new hardwood. The easiest and least expensive solution would be to install directly over the existing hardwood.

Any suggestions or recommendations would be appreciated.