When not cleaned up immediately, pet urine stains and odors can seep below your flooring surface and into the subfloor. Removing urine from subfloors takes elbow grease, but the reward is a better-smelling, more sanitary home and a well-behaved pet.
Remove the carpet or floorboards to access the subfloor. Train a black light on the floor to find spots where there is urine staining. Reapply enzymatic cleaner directly to the subfloor and let sit until it completely dries. Enzymatic cleaner works on any porous surface, including concrete and wood. Repeat treatment with enzymatic cleaner several times, as necessary.
Sand the subfloor down if the stain or smell is very stubborn. Gently remove the surface stain with a sander, being careful not to sand too deeply. You do not want to sand enough to change the height of the floor.
Paint the subfloor with an oil-based primer and sealant. Apply a second coat if stains seep through the first coat. This will lock away any residual odors.
Replace the flooring or carpeting. If the subfloor has been resealed successfully, the odors should not seep up through the new flooring.
Kayla Richard has been writing from Rochester, N.Y., since 2007. She holds a Bachelor of Arts in English writing arts from SUNY Oswego and a graduate certificate in nonprofit management from SUNY Brockport.