Use a drill, spade bit, saw, pry bar, workbench, hammer, chisel, tape measure, sandpaper, stain, wood floor finish and a paintbrush to reverse buckled hardwood cause by moisture. The floor must be dry in order to accomplish this task to prevent further damage.
Attach a spade bit to a drill and drill holes in each end of a buckled floor plank. Next, use a circular saw to cut along the length of the plank from one hole to the other. Use a pry bar to pry the cut strips of wood and to remove the remainder of the wood plank. Use a chisel to tap along the tongue end of the plank to break the portion off. Place the new planks that are cut to fit into the floor openings upside-down on a workbench, and use a hammer and chisel to knock the bottom portion of the grove off of each plank. The planks are now ready to be placed into the floor, with the tongue facing the opening. Set nails into the wood approximately a foot apart and at an angle while using a nail set to push the nails below the surface. Fill the nail holes with wood putty with remove the excess putty with a cloth or finger. Sand the boards with a fine-grit sandpaper, and stain and finish the replacement planks for the final step.