When cats spray, they deposit urine on surfaces such as furniture, doorways, floors and walls. Feline spraying is not a litter box problem. The cat is merely marking its territory with its scent. The strong odour comes from the proteins and ammonia in the cat urine. When it dries, the urine forms crystals, which are the source of the odour. To remove the smell completely, you must break down the crystals, Otherwise, the odours will return when the surface is exposed to moisture.
White vinegar eliminates both cat urine stain and odour. That's because acids neutralise basic chemicals such as ammonia, the main offender in cat urine. Combine one part white vinegar to two parts warm water and pour into a spray bottle. Soak up as much urine as possible with paper towels before spraying the affected area with the vinegar solution. Rub in the solution with a paper towel. Let the area dry. Then rinse it with warm water.
Mix 443ml hydrogen peroxide, 2 tbsp baking soda and two squirts of liquid hand soap in a bowl. Apply liberally to the cat urine and rinse off with warm water. The hydrogen peroxide kills the bacteria that contributes to the urine smell. If you don't have hydrogen peroxide, laundry stain removers with "oxy" power are a good substitute.
Baking soda neutralises odours, including cat urine. Drizzle baking soda over the sprayed area. Add one-fourth cup of hydrogen peroxide mixed with a teaspoon of liquid dishwashing liquid on top of the baking soda. Work the paste in with a brush until the baking soda dissolves into the material. Allow the baking soda to dry and then vacuum the residue.