Sanding Concrete Surfaces: Smooth Prep for Paint, Sealers & Stain

Concrete may look tough and durable, but before applying paint, stain, or sealers, it often needs sanding. From garage floors to countertops, sanding concrete removes imperfections, opens pores for adhesion, and creates a professional-grade surface.

Why Sand Concrete?

Concrete surfaces can be uneven, rough, or sealed with old coatings. Sanding eliminates high spots, smooths rough textures, and helps new finishes bond properly. Skipping sanding can lead to peeling paint, blotchy stains, or sealer failure.

Recommended Tools

• Coarse and fine wet/dry sandpaper sheets
• Angle grinder with sanding attachment (for floors)
• Hand sanding block (for countertops and edges)
• Vacuum and mop for dust removal
• Safety gear: respirator, ear protection, gloves, and goggles

Choosing the Right Grit Sequence

• 60 grit: Heavy grinding and removal of coatings.
• 120 grit: Smooths surface after coarse sanding.
• 220 grit: Prepares concrete for paint or stain.
• 400 grit: Polishes for a satin finish.

Step-by-Step: Sanding Concrete

1. Prep the area. Clear furniture, cover nearby surfaces, and put on safety gear.
2. Start with 60 grit. For floors, use a grinder; for small areas, hand sand with 60 grit (25-pack) to remove coatings or rough patches.
3. Switch to 120 grit. Smooth the surface further with 120 grit (50-pack) for an even texture.
4. Refine with 220 grit. Prepare for paint or sealer using 220 grit (100-pack).
5. Optional polish with 400 grit. For countertops or decorative finishes, polish with 400 grit sheets.
6. Clean thoroughly. Vacuum and mop to remove dust before applying finishes.

Special Cases

Garage floors: Use a grinder with vacuum attachment to minimize dust.
Countertops: Wet sand with finer grits for a polished look.
Outdoor concrete: Always seal after sanding to protect against weather damage.

Pro Tips

• Always wear a respirator—concrete dust is hazardous.
• Work in sections for large surfaces.
• Keep surfaces damp when wet sanding to reduce dust and achieve a smoother finish.

Aftercare & Next Steps

• Seal immediately after sanding to prevent dusting and staining.
• Use epoxy or polyurethane coatings for garage floors.
• Polish countertops with progressively finer grits for a glossy finish.

FAQs

• Can I sand concrete by hand? Yes—for small areas like edges or countertops.
• Do I always need a grinder? Only for large surfaces—sheets and blocks work for smaller jobs.
• Will sanding remove stains? Light stains may come out, but deep ones require grinding or resurfacing.

Watch & Learn

Sanding concrete isn’t just for pros—with the right tools and grit sequence, you can prep surfaces for paint, stain, or sealer and achieve durable, professional-looking results.