How to Sand Wooden Doors Before Painting (80, 150, 220, 320 Grit Complete Guide)

Painting a wooden door is one of the fastest ways to refresh a home’s interior or exterior. However, achieving a smooth, professional look depends on how well you sand the surface first. Old finishes, scratches, and uneven textures must be removed before primer or paint is applied. This guide will show you how to prepare doors for painting using 80, 150, 220, and 320 grit sandpaper.

Why Sanding Doors Matters

Doors are high-contact surfaces—they’re constantly touched, bumped, and exposed to wear. If you skip sanding, paint won’t adhere properly and imperfections will show through. Sanding ensures the door surface is smooth, clean, and ready for finishing.

Benefits of sanding doors include:

• Improved adhesion: Primer and paint grip better to sanded surfaces.
• Smooth finish: Removes scratches, dents, or rough edges.
• Durability: Prevents peeling or bubbling after painting.
• Professional appearance: Ensures a uniform, flawless final look.

Choosing the Right Grits

• 80 grit: Removes old finishes, varnish, or thick paint layers.
• 150 grit: Smooths scratches from 80 grit and levels the surface.
• 220 grit: Creates a paint-ready texture.
• 320 grit: Final pass for a silky surface, especially on visible panels.

Tools and Materials You’ll Need

• Sandpaper sheets: Durable sheets in 80, 150, 220, and 320 grits.
• Sanding block: Maintains even sanding on flat areas.
• Orbital sander: Speeds up large surfaces like door panels.
• Sanding sponge: Ideal for grooves and moldings.
• Tack cloth: Removes dust between sanding stages.

Step-by-Step Sanding Guide

1. Start with 80 grit. Use 80 grit (25-pack) to remove heavy finishes or rough spots. Focus on flat panels and edges.
2. Smooth with 150 grit. Switch to 150 grit (25-pack) to refine the surface. Sand lightly on moldings and trim.
3. Prepare with 220 grit. Use 220 grit (100-pack) to create a paint-ready texture that ensures primer bonds properly.
4. Finish with 320 grit. Apply 320 grit (25-pack) to achieve a silky smooth surface, especially for doors that will be painted with glossy finishes.

Special Considerations

Exterior doors: Sand thoroughly to remove weathered finishes and seal immediately after painting.

Panel doors: Use sanding sponges or folded sheets for detailed trim.

Hollow-core doors: Sand gently—veneer is thin and easy to damage.

Pro Tips

• Sand with the grain to avoid scratches showing through paint.
• Vacuum or wipe between grits to prevent cross-contamination.
• Don’t press too hard—let the sandpaper do the work.
• Always remove hardware or tape it off before sanding.
• Prime immediately after sanding to protect the wood.

Aftercare Before Painting

• Apply a bonding primer to ensure maximum adhesion.
• For glossy finishes, lightly sand between coats with 320 grit.
• Inspect the door under bright light to spot imperfections before final painting.

FAQs

• Can I skip 80 grit? Yes, if the door surface is already smooth and free of heavy finishes.
• Is 320 grit necessary for painting? For matte finishes, 220 grit is usually enough. For gloss or semi-gloss, 320 grit gives the best results.
• Do I need to sand between paint coats? A light 320 grit scuffing ensures smoother final coats.
• What happens if I don’t sand? Paint may peel, chip, or look uneven within weeks.

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 painted door. By working through 80 → 150 → 220 → 320 grits, you’ll create a flawless surface that ensures strong adhesion and a long-lasting finish. With patience and the right technique, your doors will look freshly installed once painted.