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Home > Cats > How to Get Rid of Cat Urine Smells in a Basement: Advice & FAQ

How to Get Rid of Cat Urine Smells in a Basement: Advice & FAQ

cat sitting near specimen cup and impermeable pearl litter for urine test

We love our cats, particularly their quirkiness and independence. But if your cat has gotten into the nasty habit of peeing in your basement, even if it was just once, not only is it frustrating, but you’ll also need to clean it up immediately — you don’t want that smell to set in!

This article is for unfinished basements, which commonly have cement floors. We start by looking at why your cat might be urinating in your basement, and then we walk you through the different steps that you should take to get rid of the smell.

Cat urine is a pervasive odor, but with a bit of elbow grease, you can have your basement smelling like a basement again in no time — which is hopefully a good thing!


Why Does My Cat Pee In The Basement?

Before we start going over how to remove the smell and stain of cat urine, let’s look at why your cat peed there in the first place. You don’t want this to turn into a recurring problem, so you should ensure your cat is healthy both mentally and physically.

  • Stress: Anxiety and stress can cause behavioral problems. If you’ve had a baby or brought a new person into the household, like a roommate or significant other, this can make cats stressed and anxious. They love routine, so they have been known to start urinating outside their litter boxes when major changes happen.
  • Litter Box Problems:If your cats are unhappy with the box, its location, or the litter itself, they are prone to urinating in other places. The litter box is possibly too small or in a noisy area. The litter should be a fine to medium texture, unscented, and cleaned frequently.
  • Medical Issues:A few different conditions can end up making your cat avoid the litter box, such as bladder stones and urinary tract infections. Your cat will start to associate urinating in the litter box with pain. Other conditions, such as kidney diseasediabetes, and liver disease, can cause an increase in urination, leading some cats to pee in different locations.

If there has been a sudden change in behavior and if your cat just seems out of sorts, don’t hesitate to speak to your vet. Many of these conditions are quite painful and can become serious if left untreated.


First Steps

Start by investing in an ultra-violet light that will help you find the urine stains, so you know exactly where to clean. This can come in handy if your cat has done it more than once and the stains are old. For the most part, urine stains can be seen by the naked eye, but the UV light will be much more thorough.

Turn out the lights, and run the UV light about 3 feet off the ground around the floor. Any stains will be obvious. You can draw a chalk outline around the stain so you can easily find it with the lights on. Otherwise, you might need to literally sniff out the stains.

Before you start the cleaning process, you’ll need to clean the floor and remove any kind of residue (urine or not) already there. Now on to the cleaning!

Fresh Urine Stains

If you’ve caught your cat in the act or the urine is otherwise fresh, start by gently dabbing and blotting it up with a clean cloth or paper towel. Concrete is quite porous, and if you rub at the urine, you’ll just push it further in.

Once the excess liquid has been removed, add water to the area and apply an ion-based cleanser. This kind of product works right away, so you then let it air dry and you’re done!

cat sitting near pee spot on the bed
Image Credit: Creative Cat Studio, Shutterstock

Old Urine Stains

These are much harder to get out because the smell will have set in at this point. The problem with concrete is that an old cat urine stain could have sitting there for years, but the odor will come wafting out if you get it wet.

For this type of stain, you’ll need to use several different products that will all work together to remove the smell. You’ll need a white vinegar, hydrogen peroxide, or trisodium phosphate mixture, as well as an enzymatic cleaner.

Start by selecting one of the three following mixtures:

  • Hydrogen Peroxide: Mix 2 cups of 3% hydrogen peroxide with 2 teaspoons of baking soda and a couple drops of grease-cutting dish detergent. Once it’s properly mixed, spread it over the stains and let it soak.
  • Vinegar: You can also try a vinegar and water mixture. Combine two parts of white vinegar with one part hot water. Spread it on any stains and let it soak.
  • Trisodium Phosphate: Combine about 1/2 a cup of trisodium phosphate with 1 gallon of hot water. This stuff is potent, so you’ll need to wear rubber gloves (though you should be wearing them anyway throughout this process), and you’ll probably want to wear a mask and safety goggles.

Just scrub it into the stain, and it will break down the bacteria in the urine. Keep in mind that this isn’t environmentally friendly. Let it air dry.

Once you’ve cleaned the area with one of these mixtures, it’s time for the enzymatic cleaner. These cleaners work to break down the uric acid in urine. Spray (or pour) it on the area, and let it air dry for as long as a day.

You can consider placing a tarp or plastic over the stain, so the cleaner will take longer to evaporate. This will remove the smell. You can use a concrete sealer once it’s all done, but that’s optional.

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General Advice

woman cleaning carpet
Image Credit: Pixel-Shot, Shutterstock

Don’t use any kind of ammonia-based cleaners. Cat urine itself is ammonia-based, so it will only make the urine odor stronger, and it will likely keep drawing your cat back to urinate in the same spot. Also, don’t use bleach!

Overall, you’ll want to avoid any other cleaners beyond what’s been discussed in this article. Cat urine is particularly potent, and only certain products will work. Read the instructions for any products that you purchase.

Also, you could consider cleaning the entire floor, not just where the stains are. This way, you’ll be assured that you’re getting rid of any other hidden odors, and the entire floor will be equally clean. Just cleaning a few small spots can lead to discoloration.divider-cat


These instructions can work on any concrete, so if you suspect that your patio or garage has undergone the same mistreatment by your cat, you can clean these areas with the same steps. Remember to read the instructions for any products that you purchase.

Bear in mind that these products can work on various other fluids, like vomit and feces, so they can come in handy beyond just treating your basement floor.

Remember to keep an eye on your cat, and speak to your vet if you’re at all worried. You want to be sure your kitty is in good mental and physical health.

See also:

Featured Image Credit: OKcamera, Shutterstock

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