Hardwood floors are a timeless mix of beauty and durability that pair with any design. If your hardwood floors get worn and scuffed, chances are good you won’t have to replace them; you can simply refinish them.
We say “simply” with a word of caution, though. For a pro, the process is straightforward, although there are a lot of steps that must be completed carefully.
DIYers, however, should think twice. Experience definitely counts when it comes to a good floor refinishing job. Mistakes show up big time on wood flooring, and you may end up devaluing your home’s appearance rather than improving it.
What Will a Pro Do?
A professional wood floor refinisher takes 2 to 5 days to complete a simple job, and up to two weeks for a complex job calling for custom stains and finishes. Sometimes humid weather interferes with drying times and causes delays.
A floor refinisher will do one of two things:
1. Rebuff your finish. Wood floors are covered with a clear protective coating. Over time, that topcoat can get scratched and scuffed, but the wood floor underneath may be undamaged.
If that’s the case, your floor refinisher will use a floor buffing tool and a succession of grits to restore the luster to your floor’s topcoat. The process is called screening. A new coat of clear finish completes the job. The job runs $1-$2 per sq. ft.
Screening gets a bit more complicated if you’ve waxed or used an oil soap product to clean your floors. If so, your contractor has to remove any residue before buffing to make sure the new topcoat dries correctly.
2. Sand and finish your flooring. The contractor will sand your floors down to bare wood, then apply a stain and two to three coats of finish. The cost is $1.50 to $4 per sq. ft., depending on the repairs necessary and if staining is required.
Steps in the Pro Sanding and Finishing Process Include:
Inspection. An estimator inspects your floors and takes measurements. He’ll check the thickness of your flooring to make sure there’s enough solid wood for a complete sanding job. A solid hardwood floor can take up to a dozen complete sanding and refinishing jobs during its 100-year lifespan. Laminated plank floors can be refinished at least once if the hardwood veneer is at least 1/8-inch thick.
Sanding the floors down to bare wood. This messy job uses progressively finer-grit sandpaper to produce a smooth surface. Look for companies that offer dustless sanding, meaning they hook up their sanding machines to vacuums that remove most — but not all — of the dust. You’ll still need to seal off doorways to keep dust out of the rest of your house.
Applying filler to cracks and holes.
Staining the floor. You can leave your floor natural, but if you want a certain color or tone, you’ll have to stain the floor. Staining usually requires several applications, plus sanding between coats.
Finishing coating the floor. Two or three separate coats are applied, with thorough drying time between coats. You’ll have a choice of:
Water-based finishes are eco-friendly and have low odors and VOCs. They generally aren’t as tough as other finishes.
Polyurethane finishes are the industry standard. They’re recommended for high-traffic floors and for kitchens.
An acid-cured finish is a two-part process that leaves an exceptionally tough coating. It has fast drying times, which may make it possible to apply two coats in a single day. However, some brands produce volatile odors that require you to turn off pilot lights, avoid using light switches, and leave your house until the finish is completely dry.
DIY Floor Refinishing
Floor refinishing is labor-intensive, messy, and loud. Be sure to have top-quality dust masks or a respirator, eye protection, and ear protection. Use plastic sheeting to seal doorways and keep dust out of the rest of your house.
Buffing the Floor — DIY
For buffing a worn topcoat, you’ll need to rent a buffer and buy a gallon of polyurethane floor finish ($55-$65/gallon). It’ll cost you $75 to $125 to buff out and recoat a 15-by-15-ft. room.
Note: You can’t buff out a floor that’s been waxed or cleaned with an oil soap — a favorite product used on wood flooring. You’ll have to strip off any residue before buffing; otherwise, the new finish won’t adhere.
Test the floor in an inconspicuous area, such as a closet. Buff out the old finish and apply a new coat. If the new coat dries and sticks, you’re in business. If not, you’ll have to thoroughly clean the entire hardwood floor with ammonia and water or a commercial floor cleaning product.
Sanding and Refinishing — DIY
To sand and completely refinish a 15-by-15-ft. floor, you’ll spend $125 to $250 for the drum sander, sandpaper, wood filler, and polyurethane floor finish.
A drum sander is a heavy piece of equipment that you walk behind and guide like a lawn mower. You’ll use a series of progressively smaller grits to remove the old finish and sand the bare wood smooth.
A drum sander takes a deft touch; let it linger too long in one spot, and you’ll gouge the flooring.
An orbital sander is a smaller tool you’ll use to remove the finish and sand the wood next to walls and in corners where the drum sander can’t reach.
Dealing with Super-Hard Finishes
Some varieties of prefinished hardwood flooring are coated with super-hard finishes made with aluminum oxide compounds. These tough finishes extend the life of the flooring (and a manufacturer’s guarantee) but are difficult to remove.
Although conventional wisdom says to start with heavy sandpaper grits (40-grit) and work to progressively smaller grits, in this case you’ll want to reverse the process.
Start with a medium grit (80- or 100-grit) to begin breaking down the outer layer of the finish. Once that’s accomplished, you can move to the heavier grit to remove the remainder of the finish and flatten the floor.