Having hardwood floors in a room can do a great deal to add elegance and appeal to your home. However, when you choose to have hardwood floors, there are also many maintenance and repair issues that you could have to deal with at some point. For example, one of your floorboards could start to lift and come up, which can affect the appearance of the floor and cause a squeaking problem when the floorboard is walked on.
Find the nails that are securing the floorboard to the joist. If the floorboard is lifting, then one or more nails is likely coming loose.
Pry out the loose nails using the back of your hammer or prying tool.
Remove the floorboard by prying it up with your hammer if it needs to be replaced. Otherwise, leave it in place on the floor.
Use screws that can fill in the nail holes to reattach the floorboard to the joist. Drive the screws in using a power screwdriver.