Hardwood stair treads are usually about an inch thick, compared with three quarters of an inch for floor boards, so a tread has more wood to sand than the floor beside it. The rest of a staircase is harder to work on, since risers, nosings, and inside corners need hand work and the wood under old carpet is often not finish grade.
How to refinish stairs depends on what the treads are made of and what finish is left on them.
Treads and Risers Are Different Materials
Most staircases pair oak or maple treads with painted risers made of poplar or pine. The two parts get different treatment: treads are sanded and stained or clear coated, while risers are usually painted, so the sanding has to stop cleanly at the joint between them. The side boards that hold the treads, called stringers, are commonly painted as well. A staircase with stained risers needs risers cut from the same species as the treads, which is uncommon on builder-grade stairs.
What Is Under Carpeted Stairs Decides the Job
Stairs that have been carpeted since construction often hold a surprise, because builders sometimes use lower-grade lumber on a staircase that was never meant to be seen. Pulling back a corner of carpet shows what the treads are before anyone commits to sanding. The usual findings are:
- Rows of staples and tack strip nails along the tread edges, each of which has to be pulled and the holes filled.
- Dried padding adhesive that clogs sandpaper and has to be scraped or stripped first.
- Paint or stain overspray left from the original build, which the carpet covered.
- Softwood or finger-jointed treads with visible seams that take stain unevenly.
- Gaps between treads and risers that the carpet hid.
Oak or maple treads in good condition refinish well. Softwood or finger-jointed treads can be stained, but they take color unevenly, which pushes many homeowners toward painted treads or new hardwood ones.
Stairs Take More Labor to Sand Than Floors
A drum sander cannot work a staircase, so the sanding is done with edge sanders, detail sanders, and hand tools. The rounded nosing on the front of each tread, the inside corner where the tread meets the riser, and the narrow face of each riser all need hand work. Each tread is a small surface that has to reach the same finish quality as a full room of flooring, which is why stairs take more labor per square foot than a floor.
Dust is the other difference. A staircase is an open path between levels, and sanding dust travels up and down it, so the cleanup between coats matters more than it does in a closed room. For professional help, consider dustless hardwood floor refinishing.
Screening and Recoating Works Only on an Intact Finish
Stairs with a sound finish and light surface wear can be screened and recoated. The process scuffs the existing finish and adds a fresh coat without cutting into the wood, which restores sheen to dull treads. It cannot change the color, remove the worn path in the center of a tread, or repair finish that has worn through to bare wood.
Painted treads are a separate case. Paint soaks into the grain, so removing it takes chemical stripping, sanding, or both, and a stained look on formerly painted stairs requires bringing the treads back to bare wood.
Finish Choice Affects Traction
A glossy polyurethane film is slippery under socks, and stairs make that a safety issue rather than a cosmetic one. Satin and matte sheens give more grip than gloss, and a fine grit additive in the final coat adds more.
Stairs also wear in a pattern. The center of each tread takes the foot traffic, and the finish there thins first. Darker stains show scuffs and pale wood at worn edges, while mid-tones hide that wear, so the stain color should be chosen with the wear pattern in mind. For stain ideas, see our hardwood floor stain colors on red and white oak.
Treads That Should Be Replaced Instead
Sanding cannot repair every tread. Replacement is the better route in these cases:
- The nosing is worn down or chipped so far that sanding would remove what remains of it.
- Treads are cracked or split along the grain.
- Soft spots or rot from past leaks have weakened the wood.
- Squeaks and movement come from loose treads that the old fasteners no longer hold.
- The treads are softwood and the goal is a stained hardwood look.
New treads and risers fall under hardwood stair installation, and new treads can be stained to match the surrounding wood once the work is done.
Timing Stairs Around the Rest of the House
Stairs are the only path between levels in most houses, and finish needs time to cure before it takes foot traffic. A staircase cannot be closed off the way a bedroom can, so coats have to be timed around when people need to move between floors. Waterborne finishes dry faster than oil-based ones, but both need the stairs left alone while they cure.
When floors upstairs and downstairs are also being refinished, doing the stairs in the same project keeps tread color and sheen consistent with the flooring at the top and bottom of the staircase. Treads finished a different color than the landing beside them are noticeable in a way that a mismatch between rooms is not.
Getting a Staircase Assessed Before Sanding
Checking under a corner of carpet and the condition of the nosing settles most open questions, and an in-person look settles the rest. TriArt Hardwoods works on hardwood stairs across Atlanta, Johns Creek, and Sandy Springs, and our hardwood stair installation page lists the stair work we take on. Details on finishing are on our hardwood floor refinishing page, and our contact page can set up a staircase assessment.
