Sanding Wooden Floors for Refinishing: Grit Guide for a Professional Look

Wooden floors add timeless beauty to a home, but heavy foot traffic eventually causes scratches, dullness, and wear. Refinishing restores their original charm, and sanding is the most critical step. This guide explains the grit sequence and process for sanding floors before applying stain or finish.

Why Sand Floors Before Refinishing?

Sanding removes old coatings, levels scratches, and opens the grain for stain or finish to penetrate evenly. Skipping sanding leads to uneven color, poor adhesion, and a finish that wears out prematurely.

Tools You’ll Need

• Sandpaper sheets in multiple grits
• Drum or orbital floor sander
• Edger or sanding block for corners
• Vacuum and tack cloth
• Protective gear (mask, ear protection, knee pads)

Best Grit Sequence for Floor Refinishing

• 36–40 grit: Heavy removal of old finish and deep scratches.
• 60 grit: Smooths after coarse sanding.
• 100 grit: Refines scratches and prepares surface.
• 150 grit: Optional step for very smooth floors.
• 220 grit: Final sanding before staining or sealing.

Step-by-Step: Sanding Floors for Refinishing

1. Prep the room. Remove furniture and cover vents to control dust.
2. First sanding pass. Use 60 grit (25-pack) after stripping heavy finish with coarser grits.
3. Intermediate sanding. Switch to 100 grit (50-pack) to refine the surface.
4. Final sanding. Apply 220 grit (25-pack) for a smooth, even finish.
5. Edge sanding. Use blocks or an edging sander for corners and wall edges.
6. Clean thoroughly. Vacuum dust and wipe with a tack cloth.
7. Apply finish. Stain, oil, or polyurethane depending on your project.

Special Cases

For old floors with thick varnish, start with 36 or 40 grit before moving to 60. For softer woods like pine, avoid sanding beyond 220 grit to keep stain absorption even.

Pro Tips

• Always sand with the grain of the wood.
• Overlap passes slightly to avoid uneven patches.
• Test stain on a hidden area before finishing the entire floor.

Aftercare

• Let finishes cure fully before moving furniture back in.
• Use rugs in high-traffic areas to protect the surface.
• Clean with wood-safe cleaners to extend the finish life.

FAQs

• Do I need to sand every time I recoat? Light sanding with fine grits is enough between recoat layers.
• Can I skip 100 grit? Not recommended—it ensures smoother transitions between coarse and fine sanding.
• What if my floorboards are uneven? Use a drum sander with coarse grit first to level surfaces.

Watch & Learn

With the right grit sequence, refinished wooden floors look stunning and last for years. Stock up on 60 to 220 grit sandpaper sheets to prepare your next flooring project.