Refinish Hardwood Floors (Sand and Stain)

Category: Flooring · Difficulty: Advanced · Time: 14.5h · Estimated cost: $450

Tools needed

Clear and seal the room
Remove everything including outlet covers and base shoe. Tape plastic over doorways and HVAC vents — sanding makes everything dust.
Duration: 1h
Drive any proud nails
Walk the entire floor with a nail set, sink any nails sticking up at least 1/8" below the surface or the sander will tear belts.
Duration: 30 min
First pass — 36 grit
Drum sand the field with the grain, overlapping each pass by 1/3 the drum width. Never stop moving or it'll gouge. Edge with 36 grit at walls and corners.
Duration: 3h
Second pass — 60 grit
Same pattern with 60 grit to remove the 36 grit scratches. Vacuum thoroughly between grits.
Duration: 2h
Final pass — 100 grit
100 grit final pass with both the drum and the edger. Floor should feel like glass.
Duration: 2h
Tack and stain
Vacuum, then wipe with mineral-spirit-dampened tack cloths. Apply stain with the grain using a lambswool, wipe excess after 5 minutes. Let dry 24 hours.
Duration: 2h
3 coats of poly
Apply oil-based poly with a lambswool, with the grain, thin coats. Let dry 8 hours between coats. Lightly screen with 220 grit between coats 2 and 3.
Duration: 3h
Cure and reinstall trim
Keep traffic off 24 hours, no rugs or furniture for 7 days. Reinstall shoe and outlet covers.
Duration: 1h

Oil-based poly fumes are no joke — open windows, fan blowing out, take breaks outside.
Stain and poly rags are spontaneously combustible — soak in water in a metal can before disposal.
Do NOT smoke or have any open flame in the house during poly coats.

Floors with deep cupping, water damage, or pet stains soaked through to the subfloor — they need partial replacement, not just refinishing.