Pet stains on hardwood floors are one of the most common — and most frustrating — cleaning challenges for pet owners. Urine soaks into the wood grain and subfloor quickly, leaving both a visible stain and a persistent odour that household cleaners often fail to fully eliminate. The key is acting fast and using the right products. Here's how to treat both fresh and old pet stains on hardwood floors.
What You'll Need
- Paper towels or clean cloths (for fresh stains)
- Enzymatic pet cleaner (critical for odour elimination)
- Hydrogen peroxide (3% — for set stains)
- Baking soda
- Hardwood floor cleaner (pH-neutral)
- Microfibre mop or clean cloths
Why Enzymatic Cleaners Are Essential
Standard household cleaners — vinegar, dish soap, baking soda — may clean visible staining but don't eliminate the uric acid crystals in pet urine that cause the odour. Enzymatic cleaners contain bacteria that break down the uric acid at a molecular level, fully eliminating the smell rather than masking it. This also prevents pets from returning to the same spot (they're drawn back by the residual scent). Enzymatic cleaners are available at any pet store and are the most important tool for this job.
Treating Fresh Pet Stains
Act immediately. The longer urine sits, the deeper it penetrates into the wood and subfloor.
- Blot up as much liquid as possible with paper towels. Press down firmly — don't rub, which spreads the stain. Use as many towels as needed until no more moisture transfers.
- Apply an enzymatic cleaner directly to the affected area, following the product's instructions for dwell time (usually 10–15 minutes).
- Blot up the cleaner with clean cloths. Do not over-wet the floor.
- Once the area dries completely, clean with a pH-neutral hardwood floor cleaner to restore the finish.
Treating Old, Set Stains
Old pet stains that have dried and darkened the wood are more difficult to remove and may require more than one treatment.
- Apply an enzymatic cleaner and let it dwell for the full recommended time — 15–30 minutes for older stains.
- For stains that have caused grey/dark discolouration: apply a small amount of 3% hydrogen peroxide to the stained area with a cloth. Leave it for 10–15 minutes. Hydrogen peroxide acts as a mild bleaching agent and can lighten dark urine stains in wood. Test in a hidden area first — it can lighten the finish around the stain.
- Wipe clean, let dry completely, and repeat if the stain persists.
- Finish with an enzymatic cleaner to ensure the odour is fully addressed.
When Stains Have Penetrated Into the Subfloor
If the smell persists after multiple enzymatic treatments, the urine has likely penetrated through the hardwood into the subfloor. At this point, the affected boards may need to be replaced and the subfloor treated with a stain-blocking primer before reinstalling flooring. This is a job for a flooring contractor.
Preventing Future Stains
- Apply a floor sealant to hardwood in areas frequented by pets — it fills the grain and dramatically slows urine penetration
- Use waterproof mats under food and water bowls
- Keep enzymatic cleaner accessible for immediate treatment
Professional Floor Cleaning in Toronto
Maidless deep cleans include hardwood floor cleaning across the GTA. Book your clean at maidless.ca.