What grit sandpaper for hardwood floors?

Choosing the right sandpaper grit is the backbone of refinishing hardwood floors, as it dictates how smooth the surface will be and how well the stain or finish adheres.

For the first sanding pass, use 40–60 grit sandpaper if the floor has thick, layered finishes, deep scratches, or embedded dirt. This coarse grit aggressively strips away old paint, varnish, or polyurethane, and evens out major surface irregularities. Note that coarse grit should only be used with a drum sander or orbital floor sander; hand sanding with this grit will leave uneven, deep scratches that are hard to fix.

Once the old finish is removed and the floor is level, switch to 80–100 grit sandpaper for the second pass. This medium grit smooths out the scratches left by the coarse sandpaper, preps the wood for stain penetration, and eliminates minor surface flaws like small gouges or wood grain tear-out. For floors with only light wear and no thick old finishes, you can skip the coarse grit and start directly with 80 grit.

The final sanding pass requires 120–150 grit sandpaper to create a ultra-smooth base for the topcoat. This fine grit removes the subtle scratches from the medium grit, leaving the wood surface silky to the touch. Avoid going higher than 150 grit for the final pass—finer grits can close the wood grain, preventing the stain from bonding properly and resulting in a dull, uneven finish.

For specialty hardwoods like oak (with open grain) or maple (with tight grain), adjust the grit slightly. Oak benefits from a 100-grit second pass to open the grain for richer staining, while maple needs a 120-grit second pass to avoid over-sanding and grain closure.

Always follow these critical tips: sand parallel to the wood grain to minimize visible scratch lines; vacuum thoroughly between each grit change to remove sanding dust; and use a edge sander for corners and edges that the main floor sander can’t reach, matching the grit sequence of the main floor.

Stick to the 40–60 → 80–100 → 120–150 grit sequence for full hardwood floor refinishing.