How to Repair Scratches on a Hardwood Floor

For hundreds of years, floors were finished and maintained with regular wax or oil applications. Later floors were finished with urethane, shellac or varnish. The advent and popularity of various pre-finished wood flooring products in the last two decades have made repairing wood flooring a tricky process. Before repairing a scratch, determine the floor finish. If the flooring was pre-finished (i.e. finished at the factory), the finish is most likely urethane, ceramic or aluminum-oxide. If the floor finish is not known, you must determine if the floor has a wax finish.

Things You'll Need

• Items needed to verify existing finish:
• 3 clean rags
• Scraper (i.e. carpenter's knife, razor, or floor/wall scraper)
• Mineral spirits
• Rubbing alcohol
• For wax-finished floors:
• Wood wax (for wax-finished floors)
• Wood putty (for wax-finished floors)
• 1 steel wool pad
• Stain or a wood-stain marker to match existing floor stain (possibly)
• For urethane or pre-finished floors (including engineered wood):
• Epoxy wood filler kit
• Stain or a wood-stain marker that matches existing floor

Instructions

Steps to Determine Floor Finish

1. Use a scraper to remove a sample of the topcoat in an inconspicuous location.

2. Look at the sample; wax will be much duller than a poly sample, and a poly will be thin with the texture of a paint chip. If still unsure of the finish, proceed to the next step.

3. Rub an inconspicuous area of floor using a rag dipped in rubbing alcohol. Some wax will deposit on the cloth, and the wax on the floor will turn white. If there is not a waxy residue on the rag and no white residue on the small area, the finish is not wax; proceed with "Steps for Polyurethane or Pre-finished Wood Flooring."

4. For further confirmation, rub a small area with a rag dipped in mineral spirits. A yellow reside left on the rag indicates a wax or possibly a combination of oil and wax.

Steps for Wax-finished Floors

1. Clean the scratch using wood floor cleaner, following the manufacturer's instructions.

2. Rub the scratch using a steel wood pad.

3. If the scratch has penetrated all layers of the finish so that the raw wood color is showing, stain the wood before filling the scratch. Apply stain to the scratch using a cotton swab, rag or brush. Another option is to use a stain-filled marker and "color" in the scratch.

4. Fill the scratch with wax using fine steel wool.

5. Buff with a soft cloth.

Steps for Urethane or Pre-finished Wood Flooring: Option 1

1. Clean the floor using wood floor cleaner following the manufacturer's instructions.

2. Look at the scratch and determine if the scratch has actually only "dented" the finish or if it has penetrated the finish and scratched the wood. A deep, penetrating scratch will expose the unfinished wood color.

3. If the scratch has penetrated through the finish, the scratch should be stained. Using a cotton swab, rag or brush, apply stain to the scratch. Another option is to use a wood-stain marker.

4. Fill the scratch with a clear epoxy following manufacturer instructions. Wood epoxy may be available in varying shades, making scratch repair a simple two-step process.

Steps for Polyurethane or Pre-finished Wood Flooring: Option 2

1. Clean the floor using wood floor cleaner, following the manufacturer's instructions.

2. Using your finger or a rag, fill the scratch with wood putty.

3. Wipe excess putty with a clean cloth. Allow wood putty to cure according to manufacturer's directions.

4. Stain the wood putty to match the floor. Colored wood putty is available.

5. Apply a polyurethane coating using a cotton swab, clean cloth or small brush.

Tips & Warnings

• For a temporary fix for scratches in dark wood flooring, fill the scratch with charcoal by rubbing a fresh charcoal briquette back and forth across the scratch. Wipe away excess with a damp towel.

• Never use a wax meant for other materials as the finish will be dulled; use a wax made for wood.

References

• Hardwood Floors; The Magazine of the National Woof Flooring Association; "Proceed with Caution; Fact-finding is Key Before Resanding; Bob Goldstein December 2008/January 2009 edition.
• This Old House Homeschooling; "Hardwood Floors 101, Your Complete Guide to Finding the Best Wood Floor for Your Home;" August/September 2009.

Resources

• World Floor Covering Association
• National Wood Flooring Association