How to Sand Wooden Stairs for Refinishing and Safety (60–220 Grit)

Wooden stairs take heavy daily wear, often leading to scratches, dents, or slippery finishes. Sanding is the first step in restoring their beauty and safety. With the right grit sequence, you can refinish stairs to look new while ensuring they’re safe underfoot.

Why Sand Wooden Stairs?

Sanding removes old finishes, smooths out dents, and prepares the wood for stain or polyurethane. It also reduces slipperiness by creating a fresh surface profile for finishes to bond effectively.

Tools You’ll Need

• Detail sander or sanding block for stair edges
• Orbital sander for treads
• Vacuum and tack cloth
• Wet/dry sandpaper sheets (60–220 grit)
• Protective gear: mask, goggles, knee pads

Recommended Grit Sequence

• 60 grit: Heavy removal of old finish and leveling dents.
• 100 grit: General smoothing after coarse sanding.
• 150 grit: Blending and prepping for stain.
• 220 grit: Final sanding before applying polyurethane or paint.

Step-by-Step Process

1. Prep the area. Remove carpets or runners and clean the stairs.
2. Start coarse. Use 60 grit (25-pack) sheets to strip finishes and smooth gouges.
3. Refine with 100 grit. Sand with 100 grit (100-pack) to remove 60-grit scratches.
4. Smooth with 150 grit. Use 150 grit (50-pack) to prep for stain.
5. Finish with 220 grit. Lightly sand with 220 grit (50-pack) for a silky surface ready for finishing.
6. Clean thoroughly. Vacuum and wipe dust with tack cloths.
7. Apply finish. Use stain, paint, or polyurethane for durability.

Special Cases

For oak stairs, sanding up to 220 grit is recommended for even stain absorption. For painted stairs, focus on scuff-sanding with 100–150 grit to ensure new paint adhesion.

Pro Tips

• Always sand with the grain to prevent scratches.
• Work carefully on stair edges—over-sanding can change the profile.
• Keep lighting angled to spot uneven areas.
• Use knee pads for comfort during long sanding sessions.

Aftercare

• Allow finish to cure fully before heavy use.
• Reapply protective finish every few years in high-traffic homes.
• Use stair treads or runners to extend finish life.

FAQs

• Do I need to remove all old finish? Yes—new finish won’t adhere to old polyurethane.
• Can I sand stairs by hand? Yes, but detail sanders speed up the process significantly.
• What if my stairs squeak? Sanding won’t fix squeaks—secure loose boards with screws before refinishing.

Watch & Learn

Sanding stairs requires patience but delivers big results. Stock up on coarse sheets, medium grits, and fine sandpapers to restore your stairs with a smooth, durable finish.