Exposing the floorboards in some old houses could be a cost effective alternative to installing new wooden floors. It will do the job and create some nice rustic interior look. However, floorboards were designed to be covered with a heavy layer of carpet and underlay, so draughts, squeaks and unsightly gaps are a common side effect of going back to basics. If you are aware of all the down sides of the exposed floorboards, than here is a good article by HomeBuilding & Renovating on how to expose them correctly.