Sanding Shiplap Walls for a Smooth Finish Without Rounding Edges

Shiplap interiors add timeless charm, but their crisp, shadowed gaps can lose definition if you sand them carelessly. Maintaining those clean edges while achieving a smooth, paint- or stain-ready surface takes proper technique, grit control, and attention to pressure. This guide explains how to sand shiplap boards efficiently without softening their signature lines.

Why Sanding Matters for Shiplap

Most shiplap boards arrive with small mill marks or raised grain that will show through finish coats. Sanding evens the surface, enhances adhesion, and improves touch feel—but too much pressure can round off tongues and grooves, ruining the fit or appearance. Controlled sanding ensures a flat, elegant result with tight, consistent reveals.

Recommended Tools

• Random-orbit sander for large flat runs.
• Hand sanding block for edge zones and inside reveals.
• 9×11-inch wet/dry silicon-carbide sandpaper sheets.
• Vacuum with brush nozzle and microfiber cloths.
• Painter’s tape to protect adjoining walls or ceilings.

Grit Sequence

• 100 grit: Flattening rough mill marks or resin pockets.
• 180 grit: Refining surface texture and eliminating scratches.
• 320 grit: Final pass for ultra-smooth painted or stained finishes.

Step-by-Step: Sanding Shiplap Panels

1. Prep and protect. Cover baseboards and surrounding trim with painter’s tape. Inspect each board for nails, resin spots, or burrs.
2. Level the surface. Start with 100 Grit (25-pack) sandpaper using light pressure. Keep the sander flat to prevent beveling the board edges.
3. Refine texture. Switch to 180 Grit (50-pack) sheets to smooth out scratches and even the tone. Hand-sand any grooves or tongue edges with a block to maintain crisp corners.
4. Final finish pass. Complete with 320 Grit (100-pack) sheets. This fine sanding gives painted shiplap a soft, refined feel and prevents raised fibers after priming.
5. Dust removal. Vacuum thoroughly, then wipe down the panels with a damp cloth or tack rag. Avoid excessive water on seams.
6. Prime and paint. Apply primer within a few hours of sanding to prevent airborne dust from settling into pores.

Special Cases

Pre-painted or pre-primed shiplap only needs a quick scuff with 220–320 grit to improve adhesion. For stained shiplap, avoid polishing too smooth—stop at 220 grit for better color absorption.

Pro Tips

• Keep sandpaper edges fresh—worn paper tends to roll and round corners.
• Sand in long, overlapping strokes following the board direction.
• Use a foam pad under the paper for slight contour control on irregular boards.
• Inspect under raking light before priming; any dull vs. shiny contrast signals uneven sanding.

Aftercare

• Maintain clean indoor humidity; shiplap moves slightly with seasons.
• Re-scuff lightly with 320 grit before repainting years later for optimal bonding.
• Keep extra sheets on hand—sanding between coats extends finish life dramatically.

FAQs

• Should I sand before or after installation? Lightly sand both stages—pre-sand boards flat before mounting, then final-sand joints afterward.
• Can I use an orbital sander vertically? Yes, just reduce speed and keep movement continuous to avoid vertical swirl marks.
• What grit for stained vs. painted? Stop at 220 for stain, 320 for paint.

Watch & Learn

Use sharp, high-performance abrasives for the best results. Explore eQualle’s wood sanding collection to find the perfect grit sequence for every surface, from rough pine boards to smooth primed finishes.

Conclusion: Proper sanding preserves the defining geometry of shiplap while producing a silky-smooth surface. Following the 100–180–320 grit progression ensures crisp shadow lines, consistent sheen, and a flawless finish that elevates any modern or rustic interior.