How to Sand Wooden Decks Before Resealing

Decks endure constant weathering, foot traffic, and spills. Before resealing, sanding restores the surface, removes splinters, and ensures finishes penetrate evenly. This guide explains how to sand decks effectively for lasting protection.

Why Deck Sanding Matters

Outdoor decks often gray with UV exposure and develop rough fibers. Without sanding, sealers won’t bond well, leading to peeling and uneven absorption. Proper sanding smooths surfaces and prepares wood for weather-resistant finishes.

Tools You’ll Need

• Floor sander or drum sander for large areas
• Edge sander or hand block for corners
• Wet/dry sandpaper sheets (60–150 grit)
• Vacuum or leaf blower
• Exterior sealer or stain

Best Grit Sequence for Decks

• 60 grit: Removes heavy weathering and gray fibers.
• 80 grit: Smooths splinters and levels boards.
• 150 grit: Prepares surface for stain or sealer.

Step-by-Step: Sanding Decks

1. Prep first. Clean deck thoroughly and let it dry fully before sanding.
2. Initial sanding. Start with 60 grit (25-pack) to remove rough, weathered fibers.
3. Smooth surfaces. Move to 80 grit (50-pack) for leveling and splinter removal.
4. Final prep. Finish with 150 grit (100-pack) to ready wood for sealing.
5. Clean thoroughly. Remove dust with blower or vacuum before applying finish.

Special Cases

Softwoods like cedar and pine require lighter sanding—stop at 80 grit to avoid sealing issues. Hardwoods like ipe or mahogany benefit from sanding to 150 grit for better finish bonding.

Pro Tips

• Sand along the board grain, not across, to prevent scratches.
• Replace worn boards before sanding to save time.
• Seal immediately after sanding to avoid UV damage.

Aftercare

• Re-seal regularly: Apply new coats every 2–3 years depending on exposure.
• Spot sand: Use 80–150 grit for touch-ups before reapplying finish.
• Keep clean: Sweep debris and wash deck annually to extend finish life.

FAQs

• Do I need to sand if I pressure washed? Yes—washing raises fibers that must be sanded down.
• Can I sand with finer than 150 grit? Not recommended—too fine prevents stain from penetrating.
• What if my deck boards are uneven? Use coarse grits (60–80) to level before finer sanding.

Watch & Learn

Sanding decks properly is the foundation of lasting outdoor finishes. With the right grit sequence, your deck will look refreshed and resist weathering for years.