Restoring Old Stair Treads: Sanding for Grip Without Splinters

Old wooden stair treads often lose their finish and become slick—or worse, splintered and uneven. Restoring them requires careful sanding that improves traction while keeping surfaces smooth and safe underfoot. This guide shows how to balance grit choice, sanding direction, and sealing techniques to bring tired stairs back to life.

Why Sanding Stair Treads Is Tricky

Unlike flat floors, stair treads endure direct foot traffic on small surface areas. Too smooth, and they become slippery; too rough, and socks or bare feet catch fibers. The goal is to sand out imperfections while leaving a subtle micro-texture that grips without cutting into wood fibers.

Tools & Materials

• Detail or orbital sander with edge access
• Vacuum and tack cloth
• Hard rubber sanding block for corners
• Wet/dry silicon carbide sandpaper: 120 Grit (25-pack), 180 Grit (50-pack), and 240 Grit (100-pack).

Recommended Grit Sequence

• 120 grit: Removes finish, scuffs, and splinters while flattening the tread surface.
• 180 grit: Refines grain and prepares for sealant or stain.
• 240 grit: Optional final pass for smoother appearance with non-slip finish additives.

Step-by-Step: Sanding Stair Treads for Safe Grip

1. Clean and inspect. Remove all nails, staples, or tacks. Vacuum debris so sandpaper won’t tear prematurely.
2. Start with 120 Grit (25-pack). Sand across the grain slightly to level out deep wear patterns or finish buildup. Keep motion consistent and avoid gouging corners.
3. Refine using 180 Grit (50-pack). Sand along the grain for a clean texture. Pay attention to nosing edges—these collect the most wear and need smooth rounding, not sharp transitions.
4. Optional: Finish with 240 Grit (100-pack). Use only if applying a clear satin or semi-gloss topcoat. For high-traffic stairs, leave at 180 grit for slightly more grip.
5. Vacuum and tack-wipe. Remove all dust before sealing or staining. Any residue can reduce adhesion or cause raised grain later.
6. Apply non-slip finish. Choose polyurethane or oil-modified sealer compatible with wood type. For added safety, mix in fine-texture grit additive for a subtle traction boost.

Special Cases

For painted treads, strip paint first instead of over-sanding—it’s easy to wear through soft grain. On oak or maple stairs, avoid sanding below 120 grit to preserve crisp edge definition. For pine, which is softer, keep strokes light and avoid repeated passes over the same spot.

Pro Tips

• Always sand each tread fully before moving to the next grit—don’t skip grades.
• Mark edges lightly with pencil to see where sanding coverage is incomplete.
• Use stair nosing guards or cardboard templates to protect risers from accidental scuffs.
• Maintain steady pressure—uneven sanding creates wavy reflections under finish.

Aftercare

• Allow sealer to cure at least 48 hours before full foot traffic.
• Place temporary fabric runners to protect from dust while drying.
• Inspect annually for worn finish—lightly sand and recoat to maintain grip.
• Avoid waxes that make stairs slippery; stick to matte or satin topcoats.

FAQs

• Can I sand stairs with a belt sander? Not recommended—it’s too aggressive and can dish the wood quickly.
• What if my stairs are uneven? Level deep dips with a coarse sanding block or filler before progressing to finer grits.
• Do I need to sand between finish coats? Yes—light 240 grit scuffing between coats ensures smooth bonding.

Watch & Learn

With 120 Grit (25-pack), 180 Grit (50-pack), and 240 Grit (100-pack), you can refinish wooden stair treads to a safe, durable, and attractive state—comfortable underfoot yet grippy enough to prevent slips for years to come.