A pro’s guide to sanding, staining, finishing
By Paul Bianchina
Hardwood floors are a beautiful feature in homes of any style. But if yours are showing their age and the wear and tear of scratches, sun-fading, and countless kid and dog miles, refinishing is the ideal way to breathe new life into them. Refinishing your floors will also blend in any repaired areas, and is the best way to make transitions between old and new rooms come together seamlessly.
Refinishing hardwood floors is a two-step process, with an optional third one depending on your preference. The floors first have to be sanded, then they’re coated with a new finish material. The optional step, done in between, is staining, which is done if you wish to add any type of color beyond that of the natural wood.
First of all, you have to determine if you have “real” hardwood floors that can be sanded and refinished. Laminate floors, of course, are not designed to be refinished. But more confusing are some of the engineered wood floors. These are strips of plywood or other substrate materials covered with a thin top layer of hardwood. Some engineered floors have a layer that’s thick enough to allow for one sanding.
If you’ve removed carpet from the area, be sure all the pad staples and tack strip nails are out. Fill any holes and repaired areas with putty. If you’ll be staining the floor, use a stainable putty, or a precolored putty that’s the color of the finished floor. Finally, remove the baseboards, and number them in order so you can easily reinstall them.
Sanding creates lots of dust! So, next you want to get the area ready. Tape plastic sheeting over doorways and over any cabinets. Remove anything hanging on the walls. Remove or cover light fixtures. Consider opening a window and placing a fan in front of it to draw dust outside. If your return air grill is located in the room where you’re sanding, cover it, and shut the power to the furnace so that dust isn’t circulated throughout the house.
You can rent the upright drum sander used for sanding hardwood floors at any rental yard, and they’ll supply you with the necessary sandpaper as well. These sanders are heavy beasts, and they can be a little tricky to use. Tip the sander back, start the drum in motion, then lower it into contact with the floor. Keep a firm grip on the handles, since the sander will want to pull you forward.
Don’t start the sander with the drum in contact with the floor, because it will create deep gouges that are hard to get out.
As you approach the wall, stop before you hit it. Sand with the direction of the grain, and don’t let the sander sit on the floor in one spot for long, or you’ll gouge it.
If the floor is badly scratched or warped, start with 24- to 36-grit paper. Then, switch to 50- to 60-grit paper and go over it again. For a floor that’s not too badly damaged, you can start with the 50-grit.
After doing the main part of the floor, finish off the edges using an edge sander, which can also be rented. This is like a big disk sander with casters, and is guided along the edge of the wall. Use a left-to-right sanding motion to feather in the sanding marks left by the drum sander. Corners and other hard to reach areas can be done with a pad sander. Final sanding is done to 100- to 120-grit using a sanding screen, which is similar to a floor buffer. This can also be rented.
Remember to wear a dust mask and hearing protection for all of the sanding steps. Finally, vacuum the floor to remove all remaining dust. Don’t use a damp rag to clean it, as that can raise the wood’s grain
Stain and finish
If you choose to stain the wood, that’s the next step. Liquid, oil-based stains are typically used for hardwood floors, since they’re easy to apply and don’t raise the grain. Apply some stain in an inconspicuous spot or on a scrap of the same type of wood to be sure you like the color. Make sure you have plenty of ventilation, and work from one corner toward an exit.
Apply the stain with a rag, brush, pad or roller, according to the manufacturer’s instructions. If the stain needs to be wiped off, you may find it easier to work with a second person — one applying the stain and the other wiping off the excess as needed. Allow the stain to dry according to the manufacturer’s instructions — usually at least 24 hours — before applying a top coat.
Polyurethane is a common top-finish material. It dries clear, wears well, and is easy to apply. Both oil-base and water-base versions are available.
The oil-base materials have long been the preferred choice, but water-base materials have been greatly improved in recent years, and offer a number of distinct advantages. They dry faster, clean up easier and, perhaps most important, put out a lot less odor. However, they’re generally thinner and usually require a buildup of at least three coats to get a good protective finish.
Talk to an experienced paint store for their recommendations, and follow the manufacturer’s instructions carefully for application and safety precautions.
Remodeling and repair questions? Email Paul at firstname.lastname@example.org. All product reviews are based on the author’s actual testing of free review samples provided by the manufacturers.