Q: My existing wood floor has no subfloor. To me the floor does not feel very solid. Is there anything I can do to improve my floor?
A: What kind of wood is the floor? I have seen a few oak & maple floors installed directly on the joists. Not a really great idea, in my view. I don’t think there is any practical way to “fix” what you have. If the floor is thick enough to be sanded several times, you may consider carefully removing it, laying down 3/4 sheeting and re installing your floor, or you may simply opt to go new.