Why It Smells Like Cat Pee Outside Your House

Cat pee has ammonia which gives it a strong, pungent smell. Apart from being pungent, it also has an acidic scent.

Your yard will smell like cat pee if stray cats are using it as a litter box. It may also have a strong urine smell if you empty your cat’s litter box in the yard. Another reason could be that your outdoor cat pees on the concrete in your yard. Concrete is porous, so it absorbs the urine. 

This article will explore why your yard smells like urine and also what you can do to eliminate the smell.


Reasons Why Your Yard Smells of Cat Urine

1. Stray Cats Have Made Your Yard a Litter Box

Stray cats poop and pee anywhere they please to mark their territory. A stray cat may have marked your backyard as its territory by urinating all over the place. The pungent urine smell deters other strays from coming close or encroaching.

Your own cat may also be indulging in similar behavior if it is an outdoor cat.

It may be marking both the front and backyard, especially if you live in an area with numerous stray cats.


2. You Empty the Cat’s Litter Box In Your Yard

If you dispose of your cat’s waste in the backyard, you repeatedly introduce decomposing urine and poop into the space. As the urine breaks down, it releases the strong smell of ammonia into the backyard.

Some cat parents prefer to train their feline friends to go potty outside instead of having a litter box in the house.

That means that your backyard is your cat’s toilet. And soon enough, it will begin to smell like a toilet.


3. It Could Be the Surface

If your cat is trying to mark its territory, it may have peed repeatedly on your concrete patio to keep away any other feline presence.

Unfortunately, concrete is a very porous material, and the pee may have seeped in and gotten trapped. The decomposition process continues to take place within the concrete.

On humid days, the smell may worsen as the uric acid recrystallizes inside the concrete and releases the foul odor again.

If the concrete holds too much urine, you may not be able to salvage it. You may have to replace it with new concrete or an overlay.


Cat Urine is Pungent due to its Make-Up

Cat pee has a pungent smell that lingers and grows stronger as the urine breaks down. Feline pee is typically 5% ammonia, uric acid, salts, minerals, and creatinine, and 95% water expelled from the cat’s body.

The 95% water is harmless, gets absorbed into the ground easily, and also dissipates into the environment.

However, the cocktail of ammonia, uric acid, and creatinine (all by-products of protein breakdown) becomes potent as it begins to decompose.

The initial breakdown involves the urea in the urine, which is broken down by bacteria into ammonia. The ammonia makes the pee smell pungent.

At the second stage, the pee continues to break down further, releasing thiols that make the pungent smell even stronger.

The uric acid in the urine is not soluble, so it bonds and adheres strongly to any surface it touches, from concrete to even soil.

Unfortunately, cat urine is more concentrated than human and canine urine. That is because cat urine contains a sulfur-based amino acid called felinine.

As felinine breaks down, it gets smellier and smellier. Unneutered male cats tend to have higher levels of felinine in their urine, so their pee smells the worst.

Felinine is unique to domesticated cats and their close feline relatives. This is a helpful trait in the wild as it marks a feline’s territory. But it is problematic for domesticated cats and their parents.

If you do not regularly treat the litter box and the place where you dispose of the litter, you are likely to experience the smell problem.

Also, consider neutering your male cat so that it can produce less felinine. Once a cat is neutered, it is more likely to produce urine that is not too pungent.

Unfortunately, some health conditions can make cat urine smell even more pungent and off-smelling. For example, if your cat’s urine has blood in it, it will have an unusual smell. Normal cat urine should be clear, pale yellow.

If your cat has dark yellow or red-tinged urine, it may have urethra blockage, blood clots, crystals, or infections causing distress to its urinary system.

If the pee is more diluted than the normal pale yellow, a vet will check for diabetes or kidney disease. Both diseases cause excessive thirst in your cat and the more water they consume the more dilute and clear their urine becomes.

Bad urine odors can also be caused by:

  • Tumors
  • Bacterial cystitis, a bladder inflammation
  • Bladder infections
  • Hormonal disorders in male cats

But here is something to note.

If your cat is suffering from a medical condition that affects urination, it will tend to have accidents where it pees outside the litter box. If you notice these accidents, combined with bad-smelling urine, your cat may be in some sort of medical distress.

Usually, cats are very secretive about their bowel movements, and they will use the litter box all the time unless they are sick.

Take your cat to the vet if you come across repeated urine accidents.


How to Get Rid of the Cat Pee Smell

The good news is that there are ways to get rid of the urine smell. Here are a few solutions to consider:


Water Your Lawn Regularly

Remember that cat urine is 95% water. Using water to dilute and wash away the urine is likely to clear the urine out of the patio and the concrete before it has a chance to seep in and become a problem.

Keep tabs on your cat peeing habits and where they like to pee if you have an outdoor cat. Your cat will typically pee two to four times a day.

As long as you know when your kitty will pee, you can irrigate the area within a few minutes of urination to dilute the pee and lessen the impact of the urine breakdown.

Cats also pee and poop where they did before because they seek out where the smell lingers.

Washing the pee away and training your cat to pee elsewhere can help it stop repeatedly urinating on the concrete surface.

Also, regularly water your lawn and backyard if you bury your cat’s litter in it. Watering your lawn twice a week with 1 to 1.5 inches of water is not only healthy for the grass, but it dilutes the litter and mitigates the smell of pee in it.

Allow your lawn or backyard to get up to 30 minutes of water. This solution may work if you have a stray or outdoor cat that has marked your backyard as its territory. 

Since you do not know exactly where the cat urinated, regularly watering the whole lawn may be your best option.

For this solution to work, you must have a good supply of water and also make the time to regularly water the lawn. You also have to constantly clean up after your cat to avoid urine build-up.


Build a Protective Fence

Building a protective fence around your backyard or garden will prevent strays from making your backyard their litter box.

Consider an anti-cat fence that features barbed wires. Don’t worry, the spikes on the fence are made from plastic, and they deter cats without harming them. These cat-repellent fences are available in hardware stores.

Use this as the first wall of defense.

Next, you can plant a live fence featuring thorny plants. No cat will want to venture into your garden if it has to scale thorny plants and plastic spikes just to pee.

Rose trees and cactuses are great plants to work with on a live fence.


Consider Enzymatic Cleaning Products

If the pee smell is super pungent and will not budge no matter what home remedies you try, consider using enzymatic cleaning products. An enzymatic cleaning product contains good bacteria that help to break down the odor-causing bacteria in the urine.

The nan-pathogenic good bacteria digest wastes, malodors, and even stains. In this case, they attack the malodors by producing enzymes specifically developed to break down specific bacteria that cause the bad smell.

Once the odor-causing bacteria are broken down and consumed by the good bacteria’s enzymes, the good bacteria remain in the soil for up to 80 hours and continue to act on any more pee that they come into contact with.

As long as your cat (or the strays) continues to use the backyard as a toilet, you can continually use these cleaning products to consume the bad bacteria. The continued presence of the good bacteria from the cleaning product doesn’t impact the soil negatively.

If there is no more pee in the backyard, the good bacteria will naturally and gradually die without causing any damage to the environment. An excellent enzymatic cleaning product to consider for malodors of this nature is the SIMPLE green outdoor odor eliminator.

The enzymes in enzymatic cleaning products cannot grow and reproduce on their own. They must be produced by the good bacteria in the product.

Bio-enzymatic cleaning products are safe for the environment and are easy to use. The enzymes can penetrate small crevices and cracks to work on the bad bacteria wherever they are. That is something that traditional home remedies cannot do.

When using enzymatic cleaning products, follow these steps:

  1. Clear the entire affected area. You may need to mow the long grass on your lawn or yard and remove the weeds and other unwanted plants in your garden. This ensures that you can maneuver through the space easily, and there will be less wastage of the product.
  2. Connect the water hose to the backend of the sprayer. Ensure that the nozzle of the sprayer faces away from your face. Point it down towards the ground.
  3. First, turn the nozzle on to open it up, then turn the water on slowly until you achieve moderate pressure. Now direct the nozzle towards the yard and spray liberally into the space. Once satisfied with the spray, shut the water down.
  4. Let the enzymatic cleaning product seep into the ground for ten minutes. That is enough time for it to penetrate every crack and smelly area. However, you must keep an eye on the yard to ensure it doesn’t dry out. The longer the yard remains damp, the longer the good bacteria and their enzymes have to work on eliminating the offensive odor.
  5. If there is a lot of wind or heat and the yard becomes dry, you can lightly spray the yard with more product.
  6. Finally, let the yard dry and inspect it for any lingering odor. Areas that still have the pee smell can be re-treated with the enzymatic cleaning product until they are odor-free.
  7. It is best to do the above treatment process at dusk or dawn for better chances of success. During these times, the temperatures are moderate, so it is unlikely you will encounter winds and heat that dry out the yard before the product is effective.


Consider Using Home Remedies

Just like some plants attract cats like catnip (Nepeta Cataria), some repel felines like rosemary, curry leaves, Coleus Canina, and lavender, among others. These cat-repellent plants tend to have strong scents that bother the feline sense of smell.

Some people also sprinkle lime on their backyard and front lawn so that it can absorb the odor.

Garden lime, also known as agricultural lime or dolomite, looks like pellets, and it can be spread

on the yard, flower beds, litter box, lawn, and gravel.

The good news is that it doesn’t burn. All you need is to spread the dolomite evenly on the affected outdoor surface and hose it down with a light spray so that it integrates into the soil.

However, it is critical to use dolomite and not quick lime which burns and is unsafe around plants, humans, and pets.

Baking soda and vinegar are also used to eliminate odors, but they offer superficial solutions.

Unlike the enzymatic cleaning products, these products do not have the staying power to eliminate the odor. They also cannot act effectively on the bacteria and micro-organisms trapped in the crevices and cracks.

Besides, they could be harmful to the environment or your pet.

Finally, some pet parents use mothballs to repel their cats from peeing in the backyard. Unfortunately, mothballs are harmful to the environment, your plants, and potentially yourself and your cat.

Unfortunately, cat fecal matter contains roughly 2.5 times the amount of nitrogen, potassium, and phosphorous in cattle manure. Those are dangerously high levels for your garden plants.

The feces of a cat also contain parasites and micro-organisms that cause harmful diseases to human beings. It is, therefore, not safe to allow your cat to use the garden as its litter box.

However, I recommend trying safer prevention methods instead of mothballs.


Train Your Cat

If you prefer your cat to go potty outdoors, how about training it to use a designated cat lawn? It is a section designed to be cleaned once your cat uses it. As a result, the smell of urine is significantly reduced because all you have to do is clean just that one section.

The section can feature artificial turf that your pet can urinate on, but it is washable.

All you have to do is make time for a frequent wash with soap and water. Once the place is dry, your cat can use it all over again.

If you do not want to use the artificial turf, you can consider designating an actual space in your lawn that your cat can use as a litter box. The space needs to be far from the house.

Make it like a sandbox with a little privacy. And you can attract your cat to this outdoor litter box by placing some catnip in there.

Just make sure that you regularly clean the area, put some fresh sand and also hose it down so that the water can dilute the urine.


Dangers of Cat Pee Outside Your House

Cat pee is dangerous because it contains substances that are harmful to human and animal health.


i) It Encourages Mold Growth

When pet urine gets onto an outdoor rag, it may result in the growth of mold. As your cat repeatedly makes your outdoor doormat its toilet, the lingering moisture underneath the rag attracts mold.

Strains of mold, like penicillium, can cause mild respiratory problems for your family. More dangerous strains like aspergillus can affect the lungs for longer when you and your family are exposed to it for a long time.


ii) It Encourages the Growth of Bacteria

The bad bacteria in cat urine may not impact your health if you are healthy, but they can hurt people with compromised immunities like those with cancer, HIV/AIDS, and other chronic, life-threatening diseases.

The bacteria can cause air inflammation, allergies and sinusitis, and even more challenging health issues.


iii) It Leaves Behind Concentrated Ammonia Levels

When the water in the cat pee dries and evaporates, it leaves behind a concentrated ammonia solution. Exposure to the fumes from the concentrated levels of ammonia can result in lightheadedness, fainting, and in some people with already compromised airways, difficulty in breathing.

If children play in the backyard and come into contact with the concentrated ammonia solution, they may suffer from skin and eye irritation or even skin burns.

If you come into contact with concentrated cat pee, you may be at the health risk of:

  • Damage to your airways
  • Hard coughing
  • Breathing problems
  • Tracheal burns
  • Alveolar edema
  • Bronchiolar edema
  • Respiratory fatigue
  • Respiratory infections


iv) It Tempts Your Cat to Repeat the Behavior

As long as your cat can smell the urine smell when it goes outside, it is re-tempted to keep urinating in the same place.

If you do not clean the area, your cat will see the persistent smell as an invitation to keep peeing there. As long as your cat keeps peeing in the same place, or nearby, it provides a place where germs and bad bacteria can grow and fester.


Urine Odor is a Sign to Clean up After Your Pet

Your cat may be peeing outside due to either medical or behavioral issues. A cat with a medical issue may pee outside the litter box, and its pee might have an unhealthy color. There may be some pain accompanying the urination.

If your cat has a behavioral issue that is causing it to pee on rugs, carpet, on the patio, and in the yard, despite having a designated place to pee, it is critical to patiently and calmly address the behavior and re-train your cat.

The good news is that cat pee doesn’t smell until it is too much and too saturated. So, this is a problem that cat parents can nip in the bud before it becomes an issue.

Just clean the litter box, clean up cat pee by washing concrete surfaces, water the lawn frequently, and use enzymatic cleaning products or lime.

Smelly cat pee indicates that as a cat parent, you need to step up your efforts when it comes to cleaning up after your pet and maintaining a hygienic space for your furry friend.

Not only does that benefit your cat, but it also keeps you, your family, and your neighbors safe and away from mold and bacteria-related diseases.

Writer: Mercy Nandika Amatieku

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