Refinishing Stair Treads: Grip and Gloss Balance with 100–400 Grit

Stair treads endure constant wear—foot traffic, dirt, and sunlight slowly dull both the finish and safety grip. Refinishing them requires more than just sanding smooth; you need a balance between traction and aesthetics. This guide explains how to sand, smooth, and refinish stair treads using a proper grit sequence that enhances both safety and beauty.

Why Sanding Matters for Stair Treads

Old finishes may peel or become slick over time. Sanding removes worn coatings, evens the surface, and prepares wood fibers for consistent stain or finish adhesion. Using the right grits ensures you don’t polish the surface too much, which can make stairs slippery.

Recommended Tools

• Random-orbit or detail sander for flat and corner areas.
• Hand sanding block for nosing and edges.
• Wet/dry silicon carbide sandpaper (100–400 grit range).
• Vacuum with brush attachment and tack cloth.
• Stain or polyurethane finish (optional anti-slip additive).

Ideal Grit Sequence

• 100 grit – Strip old finish and level deep scratches.
• 180 grit – Smooth and prepare for staining.
• 400 grit – Light finish sanding for gloss coats.

Step-by-Step: Refinishing Stair Treads

1. Clear and clean. Remove any old carpet, nails, or tacks. Vacuum and wipe the stairs thoroughly to prevent grit contamination.
2. Strip old finish. Use 100 Grit (25-pack) paper to remove coatings and deep wear marks. Sand along the grain, paying attention to edges and corners.
3. Smooth and refine. Switch to 180 Grit (50-pack) to even out the surface and prep for stain or sealer. Ensure consistent sanding pressure across all treads for uniform absorption.
4. Optional finish sanding. If applying a clear polyurethane, finish with 400 Grit (100-pack) wet/dry paper to achieve a silky feel while retaining traction. Lightly damp-wipe between grits to raise fibers for a smooth final surface.
5. Clean completely. Vacuum and tack-wipe every step to remove all fine dust before finishing.
6. Apply finish. Brush or roll on stain or polyurethane evenly along the grain. Add a non-slip grit additive to the final coat for safer footing if desired.

Special Cases

For painted stair treads, start with 150 grit to avoid gouging the base wood. If treads are oak, sand carefully with the grain—cross-grain scratches are highly visible under finish. For softwoods like pine, don’t exceed 400 grit, as over-sanding can reduce stain absorption and darken unevenly.

Pro Tips

• Always sand in the same direction as the wood grain for a consistent look.
• Keep your vacuum nearby—fine dust can cause finish defects later.
• Use painter’s tape along risers to prevent accidental scratches.
• For water-based polyurethane, sand lightly between coats with 400 grit to promote adhesion.
• Apply finish in thin layers; thick coats increase slip potential and drying time.

Aftercare

• Allow at least 24 hours before light foot traffic; full cure may take 3–5 days.
• Clean with a damp mop—avoid harsh detergents.
• Reapply topcoat every 2–3 years for lasting protection and shine.
• Inspect tread edges annually for chips or lifting finish.

FAQs

• Should I use a belt sander? Only for initial stripping—switch to finer tools for control and finish work.
• Can I skip 180 grit? No—jumping directly from 100 to 400 will leave visible scratch lines under stain.
• How do I make glossy stairs less slippery? Mix in a clear anti-slip additive with your final coat or lightly buff with 400 grit after curing.

Watch & Learn

By sanding progressively from 100 to 400 grit and balancing gloss with grip, you can restore worn stair treads to safe, durable beauty that lasts for years under heavy use.