How to Sand Drywall Patches for Seamless Walls (120, 150, 180, 220 Grit Guide)

When repairing holes or dents in drywall, sanding is the final step that makes patches disappear under paint. Without proper sanding, patched areas stand out, leaving a bumpy or uneven wall. By following the correct grit sequence, you can achieve professional, seamless results. This guide explains how to sand drywall patches step by step using 120, 150, 180, and 220 grit sandpaper.

Why Sanding Drywall Patches Matters

Joint compound dries hard and leaves ridges, edges, or uneven spots around repairs. Sanding smooths these imperfections, blends the patch into surrounding drywall, and ensures paint applies evenly. Skipping or rushing this step means visible flaws after painting.

Tools You’ll Need

• 120–220 grit sandpaper or sanding screens – prevents clogging with drywall dust.
• Sanding block or pole sander – keeps surfaces flat and uniform.
• Dust mask & goggles – drywall dust is extremely fine and irritating.
• Shop vacuum with brush attachment – for cleanup.
• Tack cloth or damp sponge – removes fine dust before priming.

Best Grit Sequence for Drywall Patches

• 120 grit: Levels ridges and high spots.
• 150 grit: Smooths seams and edges.
• 180 grit: Refines surface for primer.
• 220 grit: Final sanding for ultra-smooth, paint-ready walls.

Step-by-Step Process

1. Start with 120 grit. Knock down ridges around the patch using 120 grit (25-pack).
2. Move to 150 grit. Blend seams smoothly using 150 grit (25-pack).
3. Refine with 180 grit. Prepare the wall for primer with 180 grit (25-pack).
4. Finish with 220 grit. Lightly sand for a flawless, paint-ready surface using 220 grit (100-pack).
5. Clean thoroughly. Vacuum and wipe down before priming and painting.

Special Cases

For large patched areas, use a sanding pole for consistency. For small patches, a sanding sponge provides better control. Wet sanding with a damp sponge can reduce dust but takes more time and may soften compound edges.

Pro Tips

• Shine a work light across the wall to highlight imperfections.
• Always sand lightly—pressing too hard can gouge drywall paper.
• Feather edges wider than you think for a seamless blend.
• Prime immediately after sanding to lock down dust.

Aftercare

• Inspect walls after priming—lightly re-sand with 220 grit if needed.
• Store extra sandpaper flat to prevent curling.
• Keep sanding tools clean to extend paper life.

FAQs

• Can I skip 150 grit? Not recommended—it smooths transitions best.
• Do I need to sand between primer coats? A light 220 grit sanding improves adhesion and smoothness.
• Is wet sanding better for drywall? It reduces dust but is slower and harder to control.

Watch & Learn

For flawless drywall repairs, stock up from our medium grit sandpaper collection.