How to Sand Doors Before Repainting (80, 150, 220, 320 Grit Step-by-Step Guide)

Repainting a wooden door is one of the easiest ways to refresh your home’s appearance. But for a professional, long-lasting result, sanding the door first is essential. Old finishes, scratches, and uneven surfaces need to be smoothed out so that paint adheres properly. In this guide, we’ll explain how to sand doors step by step using 80, 150, 220, and 320 grit sandpaper.

Why Sanding Doors Matters

Doors are high-contact surfaces that show wear quickly. Skipping sanding can lead to peeling paint, uneven texture, or visible scratches. Sanding prepares the surface, ensuring smooth adhesion and a flawless painted finish.

Key benefits include:

• Better adhesion: Paint grips securely to sanded surfaces.
• Smooth appearance: Eliminates imperfections and old finish marks.
• Durability: Reduces peeling, bubbling, and chipping.
• Professional results: Gives a consistent, even finish across the door.

Choosing the Right Grits

• 80 grit: Removes heavy finishes, varnish, or deep scratches.
• 150 grit: Smooths rough sanding marks.
• 220 grit: Prepares the surface for primer or paint.
• 320 grit: Provides a silky finish for glossy paints.

Tools and Materials You’ll Need

• Sandpaper sheets: 80, 150, 220, and 320 grits.
• Orbital sander: Ideal for flat door panels.
• Sanding sponge: Great for edges and moldings.
• Tack cloth or vacuum: Removes dust between stages.
• Drop cloth: Protects floors from sanding dust.

Step-by-Step Sanding Guide

1. Start with 80 grit. Use 80 grit (25-pack) to strip away old paint, varnish, or imperfections. Sand with the grain to avoid scratches.
2. Smooth with 150 grit. Switch to 150 grit (25-pack) to refine the surface and remove marks left by coarse sanding.
3. Prepare with 220 grit. Apply 220 grit (100-pack) for a smooth, paint-ready texture across the door.
4. Finish with 320 grit. Use 320 grit (25-pack) if you’re applying glossy paint or want an extra-smooth finish.

Special Considerations

Panel doors: Use sanding sponges or folded sheets to reach into grooves and trim details.

Exterior doors: Remove weathered paint fully before refinishing to ensure adhesion.

Hollow-core doors: Sand gently—these have thin veneers that can wear through.

Pro Tips

• Always sand with the grain for a cleaner look.
• Remove hardware or tape it off before sanding.
• Vacuum dust between grits to prevent scratches.
• Don’t oversand edges to avoid rounding them off.
• Prime immediately after sanding to protect the wood.

Aftercare Before Painting

• Apply a bonding primer after sanding for best paint adhesion.
• For glossy paints, lightly sand with 320 grit between coats.
• Inspect under bright light before applying the final coat.

FAQs

• Can I skip 80 grit? Only if the surface is already smooth and free of heavy finishes.
• Is 320 grit necessary? For matte finishes, 220 grit is usually enough. For gloss or semi-gloss paints, 320 grit is ideal.
• Can I use a belt sander? Not recommended—it may gouge the door. Stick to orbital or hand sanding.
• How long does sanding a door take? Usually 1–2 hours depending on condition and detail.

Watch & Learn

Shop door sanding sheets: Get 80, 150, 220, and 320 grit sandpaper in convenient packs. Shop wood sanding sandpaper.

Closing Thoughts

Sanding is the foundation of a professional-looking paint job on doors. By progressing through 80 → 150 → 220 → 320 grits, you’ll remove imperfections, prepare the surface, and create a smooth texture for durable paint adhesion. With the right grit sequence, your repainted doors will look fresh, polished, and long-lasting.