When a wood floor is so worn that wax does little to improve it, it’s time for refinishing. Instead of hiring a pro for the job, you can save quite a bit of money by refinishing the floor yourself. You’ll have to sand off the old finish (making more dust than you ever thought possible), apply a sealer, and then finish with two coats of polyurethane or floor varnish.
With a rented floor sander you can sand about 200 to 250 square feet of flooring in a day. If you use a water-based acrylic sealer and water-based urethane floor finish, you could seal and top coat the floor in one day. (The floor still must cure for about a week, however, before it can stand up to heavy traffic.)
If your floors haven’t been refinished for some time, don’t automatically assume that they must be sanded down. Varnished or polyurethaned floors that are in reasonably good condition sometimes can be restored by cleaning with a good paint cleaner. Rub out any heel marks with steel wool or fine sandpaper, smooth out rough spots with fine sandpaper, vacuum away all dust, and apply two coats of varnish or polyurethane.
Sanding Wood Floors
If your floors do need sanding, you’ll have to clear all furniture and objects from the room; everything must go because you need to get at the entire floor, and you have to remove the dust between sandings. You must also clean all room surfaces before refinishing, and any extraneous objects will just collect dust that could contaminate the final finish.
Mask doors, heat registers, and any outlets to other rooms to prevent the spread of dust, even if your sander comes equipped with a dust bag. Check the floor for exposed nail-heads or raised boards, which can easily rip a sanding belt, and clean the floor of waxy materials, which will clog the belt. Fill holes, nicks, or dents with putty to match the finish. Because sanding creates so much dust, it’s best to wear a dust mask. You also should wear goggles or safety glasses.
Using Power Sanders
For most do-it-yourselfers, stopping and starting a power sander are the hardest operations. Once the big drum of a floor sander gets going, it’s fairly easy to keep the machine moving ahead at a steady pace. You can slow down over stained or dirty areas, but not too much because the belt keeps chewing through the wood at the same quick pace.
As soon as the belt starts turning, the sander should be moving across the floor. With most drum sanders, when you get to the end of the room and the belt is still turning, you have to tip the machine up quickly. Otherwise, the belt will cut a noticeable furrow in the wood that’s difficult to blend out with the edger. If you can rent a lever-action type of floor sander (the kind most professionals use), you will not have to tip up the machine at the end of a pass. Instead, a lever on the handle raises the sanding drum inside the housing.
With edgers, which spin sanding discs instead of rotating belts in a loop, you have to supply the off-and-on touch by hand. You use a medium-grit sandpaper to clean the outermost edges of the floor, and then blend the straightline drum pattern with the rotary edger pattern using fine-grit paper. If you like, after you return the rented equipment, you can use a random-orbit electric sander to get a better blend and to touch up hard-to-reach areas missed by the larger machines.