Refinish Hardwood Floors

Rent an upright, electric floor sander. Hardwood floors need refinishing approximately every 10 years, so there's no need to buy one. Sanders strip the wood of its old finish and smooth the surface for refinishing. While you can sand your floor with an electric hand sander, an old-fashioned palm sander or pole sander, you're only adding to the overall time of the project, not to mention the amount of backbreaking work. The larger, upright sanding units make the job easier and faster to complete. Make sure that you follow the directions and understand how they work before you start. Ask for a demonstration at your rental location.

The two most common types of floor sanders are drum sanders and orbital sanders. Of these two large, heavy machines, orbital sanders are the most user-friendly, especially for someone not used to working with sanders. Drum sanders can be trickier to control. Both types of sanders need to be kept in motion when the power is on or you risk sanding too deeply and causing grooves in the floor. These grooves are not repairable. Read all instructions carefully to be sure you know how to use the machine.

Attach a high-grit sheet of sandpaper to the sander and begin sanding your floor slowly and evenly with the wood's grain. Move the sander in straight, even strokes. Start in the middle of the room and work your way across one half of the floor, overlapping each pass by a couple inches. Remember to always keep the sander moving when it's on. Repeat the sanding process on the other half of the room.

Helpful Tips

Do a practice run where a piece of furniture will be placed to get a feel for the sander and to see what it does to the floor. If you make a mistake, the furniture will cover it.

Always turn the sander on with the sanding pad off of the floor. Slowly lower it onto the floor to begin.

Safety Alerts!

Sanding your floors will kick up a lot of dust. Wear safety glasses and a dust mask or respirator while you work to avoid breathing in the dust or getting it in your eyes.

Sanders operate at a very loud volume. Wear earplugs to protect your ears.

Eventually, you'll start getting too close to the walls and risk bumping into and damaging your baseboards. When this happens, you can give the upright sander a rest and use an electric edge sander or palm sander to finish the rest of the floor near the walls. Be sure to use the same grit you used when operating the large sander.

After sanding with the high-grit sheet, clean up the dust with a shop vacuum. Change to a medium-grit sheet and repeat the same sanding process. Remember to do the edges along the walls with the medium-grit sandpaper as well. Clean up the dust with the shop vacuum then swap out the sandpaper for a low-grit sheet and repeat the process again. Sanding with each type of grit in this way ensures that you get the smoothest end result. Clean dust from all surfaces with the shop vacuum and finish with a tack cloth.

Helpful Tip

Be sure to remove as much dust and residue as possible from all surfaces in the room. Besides the floor, check walls, windowsills, etc. Dust is your enemy when you begin to add the new finish.

Apply the topcoat. Carefully follow the instructions on the container of polyurethane finish regarding how to prepare and apply it to your floor. Generally speaking, you will apply the finish to the bare wood using a roller applicator or an extension pole.

Helpful Tip

Different brands and different types of finish can give the wood a different tone. So before doing the entire floor, test the finish you'll be using in a corner or other inconspicuous place of the room. This simple test will help to ensure that the finish will look the way you want.

Don't paint yourself into a corner. Start at the farthest corner from the door and apply the finish smoothly and evenly with the grain. Work your way back towards the door until you've covered every inch of floor space. Keep a small, angular-bristle paintbrush handy for any spots that you can't get to with the roller.

Let the first coat dry completely. Dry time varies for each brand and each type of finish—it will usually take anywhere from three to eight hours, but read the product label and follow the specified instructions for best results. Afterward, use a pole sander and a palm sander with an ultra fine-grit sandpaper to lightly sand the floor again. This will roughen the surface a bit and help the next coat adhere more effectively. Clean up the dust from sanding with the shop vacuum and a tack cloth. Apply the next coat like you did the first. In some cases, you may find you need more than two coats. If so, simply follow the method you used for the first and second coats for the next.

Once you’ve completed all your coats, let the floor dry overnight, or for 24 hours. At that time, your new refinished floors should be ready to walk on. However, wait a couple of days before moving back furniture or rugs, etc. You want to be sure that the finish has completely dried and won't be marked up by shoes and furniture legs when you move everything back into the room.

Nice job! Now your wood floors look renewed and refreshed.