How to Sand Wooden Doors for Exterior Refinishing (60–320 Grit)

Exterior doors face constant exposure to sun, rain, and temperature changes. Over time, finishes peel, crack, or fade. Sanding is the essential first step before repainting or staining to restore both beauty and durability. This guide covers the grit sequence and techniques for exterior door refinishing.

Why Sand Exterior Doors?

Weathered doors often have peeling paint, faded stain, or rough surfaces. Sanding removes old finishes, smooths damaged wood, and creates a clean surface that new coatings can bond to. Without sanding, finishes will fail quickly outdoors.

Tools You’ll Need

• Orbital sander for flat panels
• Sanding block or sponge for edges and trim
• Vacuum and tack cloth
• Wet/dry sandpaper sheets (60–320 grit)
• Protective gear: mask, gloves, and goggles

Recommended Grit Sequence

• 60 grit: Stripping heavy paint, varnish, or peeling finishes.
• 120 grit: General smoothing after stripping.
• 220 grit: Prepping bare wood for primer or stain.
• 320 grit: Final sanding for a smooth finish before topcoats.

Step-by-Step Process

1. Remove hardware. Take off handles, locks, and hinges, or tape them carefully.
2. Start coarse. Use 60 grit (50-pack) sheets to strip away old finishes and level damaged spots.
3. Refine with 120 grit. Smooth the surface with 120 grit (50-pack) wet/dry sheets.
4. Prep with 220 grit. Use 220 grit (100-pack) to ready the wood for stain or primer.
5. Finish with 320 grit. Lightly sand with 320 grit (25-pack) for a silky surface before applying topcoat.
6. Clean thoroughly. Vacuum and wipe down with tack cloths.
7. Apply finish. Prime, stain, or paint with exterior-grade products.

Special Cases

For solid wood doors, sanding down to bare wood provides the best results. For veneer doors, avoid grits below 120 to prevent sanding through thin layers. For metal-clad exterior doors, light scuff-sanding with 220 grit is sufficient before repainting.

Pro Tips

• Sand with the grain to avoid visible scratches.
• Work in shaded areas—direct sun can cause finishes to dry too quickly.
• Always use exterior-grade primer and topcoat for durability.
• Check edges and panels carefully—these areas often peel first.

Aftercare

• Reapply protective finish every 2–3 years depending on exposure.
• Clean doors with mild soap and water—avoid harsh cleaners.
• Inspect for cracks or peeling annually and touch up as needed.

FAQs

• Do I need to sand all paint off? Yes—especially for exterior doors, removing peeling or old finishes ensures better adhesion.
• Can I use a heat gun instead of sanding? A heat gun can strip finishes but sanding is still needed for smoothness.
• What grit is best before repainting? 220 grit provides ideal adhesion for primer and paint.

Watch & Learn

Refinishing exterior doors starts with sanding. Stock up on coarse grits, medium sheets, and fine papers to restore and protect your doors against the elements.