How to get cat pee smell out of wood floors (stain and smell)

How to remove cat urine from wood

1. 1

   Find every spot with a black light

   In a dark room, scan floors, baseboards and the lower walls with a black light. Mark each glowing spot with a piece of tape. Cats that spray often hit vertical surfaces, so check baseboards and door frames carefully.

   Why: Urine contains molecules that glow under UV light, which reveals old spots you can't see. Other substances can also glow, so the light finds candidates, not proof.

2. 2

   Blot fresh urine immediately

   Press a thick layer of paper towels onto fresh urine and keep replacing them until almost nothing comes up. Don't spread it into the gaps between boards.

   Why: Wood is porous, and urine soaks into worn finish, seams and the edges of boards. The less that gets in, the less odor you'll fight later.

3. 3

   Wipe with a finish-safe cleaner

   Clean the spot with a wood floor cleaner suited to your finish, using a well-wrung cloth, and dry it immediately. Avoid ammonia or vinegar cleaners.

   Why: Removing surface residue lets the enzyme cleaner work on the urine itself. Ammonia and vinegar smells can encourage a cat to come back to the same spot.

4. 4

   Apply an enzyme cleaner

   Test the enzyme cleaner on a hidden spot of the same wood first. Then apply it to the marked area, following the label's contact time, using enough to reach the urine but never leaving a puddle. Keep pets out of the room.

   Why: Enzymes break down the felinine, urea and other residue that produce the smell. Wood is damaged by standing water, so the amount has to be controlled.

5. 5

   Wipe dry and ventilate

   When the contact time is up, blot up any remaining liquid and let the area air-dry with a window open or a fan running. Some odor can linger until it's completely dry.

   Why: Moisture left in the seams swells the wood and can carry urine deeper. Fast drying protects the floor.

6. 6

   Check the finish and repeat

   Once dry, smell the spot up close and look at it in daylight. If the odor remains and the finish is intact, repeat the enzyme step. If the wood or finish is dark, gray or cloudy, plan to refinish or replace that section.

   Why: Urine that reacted with the finish or soaked into bare wood can't be cleaned out by enzymes.

Why cat pee smells so strong

Cat urine contains felinine, a sulfur-containing amino acid that's specific to cats. Felinine itself doesn't smell, but it breaks down into a volatile thiol, 3-mercapto-3-methyl-1-butanol, with a strong sulfur odor. Intact males produce much more felinine than neutered males or females. On top of that, bacteria break urea down into ammonia, the sharp smell of stale urine, and uric acid salts dissolve poorly in water, so residue stays put.

That's why air fresheners fail: they leave the residue, and the odor can come back in humid weather. The full picture is on cat urine stains, and the same chemistry applies to pet smells generally.

What wood can and can't take

Sealed wood with an intact finish is the good case: the urine mostly sits on top and in the seams, and quick cleaning plus an enzyme cleaner usually works. Wood floor guidance says never to wet-mop or steam-clean, and liquid left standing on wood makes it swell and then shrink.

The sources pull in different directions here. Pet-odor guidance says to saturate the area with enzyme cleaner and let it air-dry, while wood-care guidance says never let liquid stand on wood. On floors, use enough to reach the urine for the label's contact time, then blot. If urine has discolored the varnish or paint, the acid has affected the finish, and humane societies say it needs to be stripped and refinished, painted, or the boards replaced. Odor in porous, unfinished wood may need repeated treatment, or removal of the wood.

By situation

Fresh accident on sealed hardwood

Blot immediately, wipe with your floor cleaner, and apply an enzyme cleaner. Caught within minutes on a good finish, there's usually no lasting smell or mark.

Old cat pee smell in hardwood floors

Find the spots with a black light. If the finish over them is intact, repeat enzyme treatments, letting each dry fully. If the wood or finish over a spot is discolored, the urine has affected it, and sanding and refinishing, or replacing boards, is the realistic fix.

Cat spray on baseboards

Spraying hits baseboards, door frames and walls. Treat painted baseboards like floors, but check the paint: if it's discolored, it needs repainting. Urine that soaked into drywall behind them is rarely salvageable, and cats keep spraying walls left untreated.

Unfinished or worn wood

Bare wood absorbs urine deeply. Expect several enzyme treatments with full drying between them, and be prepared to sand, seal or replace the wood if the smell persists.

Wood furniture

Test the enzyme cleaner on a hidden area, because some finishes, like shellac, are sensitive. Use it sparingly and dry it right away. For antiques, ask a furniture conservator or refinisher.

The smell came back after cleaning

If you used another cleaner first, residue may have weakened the enzymes. Clean the spot again, rinse it with a damp cloth, then reapply the enzyme cleaner. Old enzyme products can lose strength, so use a fresh one.

What not to do

• Don't clean with ammonia or vinegar. They don't remove the urine smell from a cat's point of view, and ammonia smells like urine, which can draw the cat back.
• Don't wet-mop, flood or steam-clean the floor. Standing water and steam damage wood and its finish, and heat can set urine odor.
• Don't mix bleach with ammonia or vinegar. Bleach plus ammonia makes chloramine gas; bleach plus an acid makes chlorine gas.
• Don't rely on fragrance or masking sprays. The residue stays, and the odor returns, especially in humid weather.

Other methods that work

Oxidizing pet cleaner

If other cleaners have already been used on the spot, humane-society guidance suggests cleaning first with an oxidizing pet cleaner, then applying the enzyme cleaner.

Caution: Test it on the wood first, rinse between products, and never mix them.

Hydrogen peroxide

Often suggested for urine on wood. It's traditional advice with weak evidence, and pet-odor guidance lists peroxide among products that interfere with enzyme cleaners.

Caution: It can lighten wood and finishes. Test in a hidden spot, and don't use it right before an enzyme cleaner.

Sanding and refinishing

When urine has discolored the finish or soaked into the boards, refinishing that area, or replacing the boards, is the fix humane societies point to.

Caution: A flooring professional can tell how deep the damage goes.

Stain still there?

The finish turned white or cloudy where you cleaned

Moisture got into the finish. Dry the area thoroughly. If it doesn't clear, the finish may need recoating by a professional.

The smell is strongest at a seam between boards

Urine got under the boards or into the subfloor. Repeat the enzyme treatment along the seam, and if it persists, have a flooring professional lift the boards.

The cat keeps going back to the same spot

Make sure every trace is gone with the black light, and cover the area temporarily. A sudden change in a cat's habits is worth a vet visit, since a painful urinary problem may be the cause, and neutering reduces urine marking.

Safety

• Wear gloves and wash your hands after cleaning urine.
• Never mix chlorine bleach with ammonia or acids.
• Keep pets out of the room until treated areas are dry.

Never mix cleaning products; see chemicals you must never combine.

Questions

Cat urine on other surfaces

• Cat urine stains: the complete guide
• Cat urine on carpet
• Cat urine on clothes
• Cat urine on a couch
• Cat urine on a mattress

Other stains on wood

• How to clean wood
• Dog urine on wood
• Mildew and mold on wood