There is nothing worse than trying to get rid of the foul urine smell from pets, dogs, and cats out of the concrete of your garage floor or basement. It seems like no matter how much you clean, the smell won’t go away. This is particularly true for cat urine. We will cover the best methods for removing cat and pet urine odor in your concrete. We will include how to seal your garage floor or basement to block any odors that may remain from concrete with particularly heavy urine issues.
Most concrete with pet urine odor must be treated in a two-stage process. Sometimes it may even require an additional stage depending on the type of urine odor remover or pet enzymatic product used.
In addition, it also helps to use a wet vac if you have one. It is most helpful if you have a basement with urine odors and no drain available. The wet vac helps draw bacteria out of the concrete during cleaning. Carpet cleaners can work in a pinch for vacuuming up liquids as well.
Pet urine odor and stains won’t go away with normal cleaning
We guess you may have already tried cleaning the urine stains to remove the odor in the concrete without good results. The stain may or may not be gone, but the smell remains. That is why it’s important to learn why the urine odor still exists and why conventional cleaning methods do not work. Doing so can save you some time and expense.
Concrete is actually porous like a sponge. If liquid is allowed to sit for a while, it will absorb most anything. This is why it’s hard to get stains out of concrete.
When urine is introduced to concrete and allowed to dry, the uric acid crystals present in urine bond tightly to the concrete. Unfortunately, these crystals form deep within the pores and capillaries of the concrete since the urine was allowed to soak – sometimes multiple times for days or even months.
Despite numerous cleanings, uric acid crystals are insoluble and will not bind with regular soaps and other cleaning agents. Thus, the crystals stay attached to the concrete and the smell remains.
The smell may dissipate temporarily after a good cleaning, but as soon as any moisture or moisture vapor is introduced again, it can come back just as strong as before. Basements can be particularly susceptible to this.
The reason the smell returns is that uric acid salts allow crystals to reform as soon as moisture (humidity for example) is introduced. This releases a gas that has a pungently strong odor.
The best way to stop the smell is to use an enzymatic cleaner that attacks and breaks down the uric acid crystals and separates them from the concrete.
Steps for removing Cat and pet urine odors from concrete
- Identify urine areas in concrete using a U.V. light or black light
- Clean the affected areas with a proper cleaner to remove bacteria
- Let the affected area dry throughout – not just the surface
- Treat the affected areas with an enzymatic pet odor remover
- Do not skip any steps or take shortcuts
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How to identify urine odor stains in concrete
To get the best results from an enzymatic pet urine cleaner, you must first identify the exact areas in the concrete affected by the urine.
Many times the source of pet urine odor can easily be identified, such as an area where pets were kept in a pen. However, sometimes it may not be so easy to detect.
This is often the case for people who have moved into a home that previously had pets, only to find that the garage floor reeks of a foul urine smell. Stains may have previously been cleaned thus hiding the source of the odor.
One tool that does a good job of identifying pet urine is a UV light or black light. These here from Amazon do a good job.
Close the doors and then turn on the black light. Hold it no more than three feet off the concrete as you scan the floor in sections. Old urine stains will stand out as blue, green, or yellow markings on the concrete.
We like to encircle the far outside area with arrows pointing toward the urine stain. Chalk works well for this provided you don’t get it wet. Be sure to check the first two feet of your walls from the floor up as well. Sometimes cats will spray urine on the walls. This requires removing and replacing the affected section of drywall to get rid of the smell.
If for some reason the UV light does not reveal any stains, the old standby that will work is your nose. This takes longer but it is effective. Open the doors to air out the garage and get rid of the immediate smell. After that, get down on your hands and knees and start sniffing. Trust us; you will know when you find it!
Clean the pet urine stains with TSP
After you have identified where the urine is located, it’s important to properly clean the area to rid the concrete of bacteria and other residual urine elements. Contrary to popular belief, most enzymatic cleaners do not remove bacteria.
Once you know where the urine stains are, the first step is to scrub the area with a strong solution of ½ cup TSP (Trisodium Phosphate) to 1 gallon of hot water. TSP mixed at this ratio is very strong. Gloves and eye protection should be worn for safety.
What the TSP does is remove all the bacteria, most if not all of the stains, as well as remove other residue left from the urine. It will leave only the uric acid crystals behind. This will allow the enzymatic pet urine cleaner to work faster and more efficiently at removing the uric acid crystals.
Pour the hot TSP solution onto the urine stain or identified area and scrub it with a short bristled nylon brush. A deck brush works well for this. Make sure that you keep the area wet for at least 10 minutes or more to allow it to soak into the concrete. The solution will follow the same paths as the urine did and will need some time to work its way down into the concrete.
Do not be surprised if the smell increases as you soak the concrete. It is a combination of urine residue and uric acid crystals reacting and releasing gas from contact with the water.
Once the area has been scrubbed and allowed to soak long enough, pour clean hot water over the treated area again and then vacuum up the water with the wet/vac. Carpet cleaners will work for this as well. You will want to do this at least twice. For heavily treated and soiled areas, three times would be better.
This hot water rinsing will remove the TSP solution and help to suck up any remaining urine residue that is in the concrete. Treat any additional areas in the same fashion (scrub, soak, rinse), and then allow the concrete to dry at least overnight. 24 hours or more is best. Pet urine enzymatic cleaners work best when the concrete is completely dry before treatment.
As a note, the TSP may create a whiter-looking area on your garage floor since it is getting the concrete very clean. If that is the case, you may want to scrub the rest of your concrete after you are done with the same TSP solution. This will achieve a more consistent (and clean) look on the floor.
Using a hose with a high-pressure nozzle works fine for this to speed up the rinsing process. You are just removing dirt at this point and not sucking up urine residue. We have more tips for cleaning a garage floor here.
Apply pet urine enzymatic cleaner to concrete
Pet enzymatic cleaners work by using bacteria (the good kind) to digest malodors, waste, and stains. These bacteria produce enzymes that break down the molecules of the uric acid crystals into smaller bits. This allows the bacteria to digest the smaller bits and break them down into the two basic components of carbon dioxide and water. They are the best product for removing the smell from cat urine.
Because you are working with concrete and not carpet, we suggest using a product that is available in concentrate or gallon jugs and not something that comes in a spray bottle. Unlike carpet, you will need to use liberal amounts of the enzymatic cleaner.
The reason for this is that most enzymatic products need some sort of exchange with air. Since most of the uric acid crystals are deep in the concrete, it takes more time for the required air exchange. It will also take time for the concrete to absorb the enzymatic cleaner. Since some of the cleaner will evaporate on the surface as it soaks in, more will need to be used.
One of the best products for removing cat, dog, and pet urine odor is Rocco & Roxie Professional Strength Stain and Odor Eliminator. It has worked wonders for us and we highly recommend it.
It has stellar reviews and we know of more than one kennel that uses this as its go-to odor eliminator. Furthermore, it’s available in gallon jugs and does an excellent job when given time to work. You can find it here on Amazon.
There are many other products with good reviews that you can shop for here if you prefer. We recommend staying away from the products that require mixing with carpet shampoo as these will not be as effective on concrete.
Be sure to follow the directions for the product you choose. Pour it onto the stained area and then start scrubbing it in with a deck brush. Keep it wet for at least 10 minutes or more. You want the concrete to absorb as much of the solution as possible.
For the best results, temporarily cover the wet area with a cheap painter’s tarp to help avoid evaporation of the solution. This will give it more time to soak into the concrete. Rinsing is not required. The enzymatic cleaner will break down the uric acid crystals into carbon dioxide and water which will dissipate on its own.
Particularly bad-smelling areas may require multiple treatments. This is because it will take time and more enzymatic cleaner to soak into the concrete and do its work. Remember, you may be dealing with an area that allowed the concrete to soak in urine for weeks or months.
DO NOT RUSH THE PROCESS! This is the biggest mistake people make. As we stated, enzymatic urine odor removers require time for the good bacteria to digest the uric acid crystals. If you rush the job, you will not be successful.
Sealing concrete from pet urine odors
On rare occasions, it may require sealing the concrete to prevent any residual pet urine odor from working its way back to the surface. Sometimes people want to do this even though the odor is gone. They just don’t want to take the chance of it returning.
The only type of sealer that will work is a non-breathable, topical concrete coating. Garage floor coatings are a great example. Garage floor coatings are film-forming and do not breathe. They will block odor molecules from transferring through the coating. Acrylic sealers and penetrating sealers will not work. They are breathable and will allow the odor molecules to pass through.
The least expensive to apply is EpoxyShield by Rust-Oleum. You can find it here on Amazon. Do not use 1-part epoxy paint. 1-part epoxy paint is paint and not a true 2-part epoxy coating. Paint breathes and will not seal out the urine odor.
Applying a garage floor coating requires grinding or etching the concrete before application. If you know that you will be applying a coating before you treat your garage for pet urine odor, we recommend treating the concrete after you grind or acid etch.
The concrete prep process will open the pores of the concrete and allow pet enzymatic cleaners to be absorbed into the concrete more easily. It will allow slightly more air transfer as well. The result will be a quicker and more effective use of the cleaner.
Once the coating is applied and has fully cured, it should effectively block any odors that remain in the concrete.
Rachael says
I got new carpet and padding last year after we moved into our home. The previous owns had dogs pee all over I think. Going into the fall it seemed the smell went away with the new carpet. But now unfortunately with the humidity the smell has come back. What can I do?
Shea says
Hello Rachael. The reason for the odor is the urine in the concrete. The new carpet and padding is not going to block it. Your only solution is to pull up the carpet and padding and then clean the concrete and use the enzymatic odor remove as we describe.
Regina says
Is the PERT cleaning method used by Chem Dry necessary to get cat urine out of concrete? It is very expensive. Your method sounds reasonable. Is the PERT a rip off?
Thank you
Shea says
Hello Regina. As far as we know, the P.U.R.T. method is used primarily for carpet. We don’t know enough to verify how well it works. The method we list is for concrete only and not for carpets or other flooring.
Sheri says
Ok, so is the TSP method one option and the pet enzyme cleaner another? Or do you do the TSP treatment , then follow that 24 hours later with the pet enzyme cleaner? Confused…
Shea says
Hi Sheri. You need to do both. As we explain, TSP will remove the bacteria, stain, and other residue, but it does not remove the uric acid crystals. The crystals are what causes the odor, particularly when they get damp. When the area is first cleaned with the TSP, it allows the enzymatic cleaner to work faster and more efficiently. It does not do as good a job if the area is not cleaned up first.
Melissa Powell says
I have cats. All is removed from floor of closet,, standard bedroom closet. For whatever reason, one of my cats is peeing in there. Have no idea why. Peeing at one end of the closet, no doors. I need to clean it up. I have tried vinegar type cleaners and I now put down a pee pad. I take that outside and clean it with soap and water and let dry. I am pretty sure I have not done enough. To make this worse, one of my cats is pooping at the other end of the closet. Do I use these methods to clean this up? I have also used your recommend stain and odor eliminator, not great. Any suggestions. Getting rid of a cat is unacceptable.
Shea says
Hello Melissa. We have never suggested that anyone get rid of their pet. The process we outline above is for concrete floors only. It explains how to identify exactly where the urine is, how to remove the bacteria, and then how to remove the uric acid crystals (which cause the odor) by using the enzymatic cleaner. Though no odor removing process is guaranteed, the above process has proven time and again that it works very well. If you don’t follow the procedure and delete a step, then the chance of eliminating the odor is greatly reduced.
Ted says
This article and comments have been really helpful. Thanks for sharing.
We moved into a new house this spring and the previous owners had numerous cats that had free reign over the unfinished basement and the smell is pretty bad. We’re hoping your recommended TSP deep clean and enzyme treatment’s enough to eliminate the problem (or at least make it substantially better) and we can avoid the need to seal the floor, as we’re not trying to make it a livable space, we just want the smell out we do have need to go down there occasionally for storage and it can seep into main house as well.
I have a couple of questions I’m curious about —
– are there any suggestions/tips about doing the basement in sections? We’re cramped a bit for storage, and would prefer not to temporarily move everything out or rent a pod. It might be easier to clear 1/4 or 1/5 of the basement floor out a time, perform the 2 steps (deep clean and enzyme treatment with ample drying time in between), and when dried pushing everything over and starting on a new area.
Other than obviously taking more time, anything else to think about that might discourage us from this approach?
Also, there’s a 3×4 area of the basement floor where the concrete is broken up and its mostly just exposed dirt. Not sure the best strategy for that. In theory at some point we might try to re-pour that section. In the meantime, I’m not sure how to clean dirt. Maybe the best we can do is to spray a good quantity of the enzyme solution in that area.
Lastly, is there guesstimate for how much concrete floor area a gallon of Rocco & Roxie would cover. It’s hard to gauge from their website.
Thanks. again.
Shea says
Hi Ted. Yes, you work in sections. Just be sure to slightly overlap each section as you go. Make sure to first identify all areas where urine is present by using a black light. Check the walls as well. Yes, the coverage rate is hard to gauge due to the many surfaces it is used on. Concrete porosity varies as well. We would recommend starting with a gallon and then determine the rate from there. When you apply it, it will be helpful to cover those sections with plastic to restrict evaporation. For dirt, it’s usually best just to remove it from the offending area and replace with fresh soil.
Eric says
Hello! The Rocco & Roxie product you are recommanding is difficult to obtain in my neck of the wood for a reasonable cost, even by web order. Any other brands that you may suggest?
Shea says
Hi Eric. Since we don’t know what neck of the woods that is, we recommend that you check the reviews of the enzymatic pet odor cleaners that are available to you. Make sure that the one you choose works on concrete.
Carol Herb says
Is it safe for us to put the cat litter box back in the basement after using this method to clean the concrete floor?
Shea says
Hi Carol. If you are asking if the cleaning methods are safe for the cat to return, then the answer is yes.
Jenn says
Thank you for all this information! Can you tell me if this method will work for strong cat urine stains and smell on an epoxy floor?
Shea says
Hi Jenn. Are you sure it’s an epoxy floor and not paint? Epoxy forms a coating that is impermeable and usually will not hold odors. Paint is not impermeable and urine can get through eventually. If it’s epoxy, I would just try the TSP first. Don’t let it dwell for long though. Just a light scrub and then rinse. If it’s paint, it may be more difficult because it’s possible that it has gone through to the concrete below. You can try these steps for paint, but if that does not work, then you will need to remove the paint to get to the bare concrete underneath.
Jennifer Boone says
Yes, it’s definitely epoxy. It has become discolored and odorous due to cat urine. I plan to try the TSP first and then the enzyme to neutralize the smell. I just don’t want either to harm the epoxy finish. Can a thin layer of epoxy be applied over the original epoxy to reseal the floor?
Shea says
Go ahead and treat it then in the steps we outline. Depending on the quality of the epoxy, the discoloration may or may not be permanent. You didn’t mention having a clear coat, so we are assuming it’s not a quality epoxy system? You can apply epoxy over that area then, but it will stand out almost as much. The reason is that coatings do not blend together like paint on a wall does. The new epoxy will look much glossier and the overlap marks will be very evident.
Rachel says
I already painted oil-based Kilz over my gypcrete subfloor. Do I need to remove the Kilz in order for the enzyme cleaner to work?
Shea says
Hi Rachel. If you covered the area up with Kilz, then nothing is going to work. Cleaners and odor removers need to to penetrate the surface in order to work. You will need to remove the Kilz if you still have an odor.
EpicInTx says
This is great info, thank you.
We foster dogs and puppies and have an area outside on our concrete paver patio that we use for the puppies when they want some time outside. Since they’re puppies, there are numerous urine and fecal stains in the area and it’s right outside the back door so the smell is not ideal either, especially when it rains.
My question is regarding the rinse step for the TSP – do we need to vacuum up the rinsed out TSP so it doesn’t absorb into the unaffected areas of the deck or is it ok to let it run out across it and dissipate? The affected area is small, only about 5 x 10 but opens up to the deck area which is quite large and there isn’t anywhere close that we could direct the rinsed water directly to the ground. Ideally I’d like to apply the TSP then rinse it with hot water, then hit it with the hose or power washer and call it a day.
Shea says
Hi EpiclnTx. If you don’t completely hose the waste rinse water off the concrete, it will just settle back in elsewhere and eventually begin to stink. Use a wet rated shop vac to suck up the rinse water if you can’t do that. Also – if you don’t treat the area with an enzymatic pet odor remover afterwards in order to remove the uric acid crystals, it will just stink again when it rains.
Randy says
Just wanting to get clarification on something. The article stated the following:
“Applying a garage floor coating requires grinding or acid etching the concrete before application. If you know that you will be applying a coating before you treat your garage for pet urine odor, we recommend treating the concrete after you grind or acid etch.
The concrete prep process will open the pores of the concrete and allow pet enzymatic cleaners to be absorbed into the concrete more easily. It will allow slightly more air transfer as well. The result will be a quicker and more effective use of the cleaner.”
Is it best to etch/grind the concrete surface before using the enzymatic cleaner or before using both the TSP and the enzymatic cleaner?
Thank you.
Shea says
Hi Randy. Prep the floor for the coating first. This will open the pores and give you the best results for both the TSP and enzymatic cleaner. Just make sure the concrete has thoroughly dried throughout (not just the surface) before applying the enzymatic cleaner. Don’t rush to apply the coating while the cleaner is doing its work. Otherwise, you will be sealing out air transfer and the cleaner will stop working.
Randy says
I have a follow up question. So, we applied 3 rounds of hot TSP (scrubbing it in and letting it sit for more than 10 minutes each time). After each round, we would put clean hot water and scrub and use a wet dry vac with squeegee to get all the liquid up. We let the floor dry for 3 days. We are in Utah and there is very low humidity here right now, so we felt the concrete floor was dry throughout. For the room which was the worst (a 12 feet x 12 feet room), we applied almost a whole gallon of the Rocco & Roxie enzyme stuff. We even sprayed the solution on the seal plate since we had the baseboards off the wall (just in case). The previous owners had carpet that we took out and all the carpet tack strips were fairly saturated with urine when we took them out. We also put 1 mil plastic down over the solution, to allow it to not evaporate too quickly.
After 3 days, there was still a slight smell of urine, so we hit the worst spots that we had found with the black light in the beginning. There were so many spots. We are now 1 day later and I got the black light out again and notice that all the spots still light up. I expected with the amount we put on (2 heavy doses), that the black light would not show up anything anymore. We don’t smell urine, but the enzyme solution fragrance does seem to mask the urine smell for at least 48 hours. It was not until after the first 3 days of the first treatment, that we could actually smell the urine.
Should the black light still show up even if the urine is gone or am I going to have to buy more product. We bought 6 gallons of the enzyme and have applied 5 gallons so far in our 1351 sqft home.
Shea says
Hi Randy. What you see under the black light is phosphorous from the urine. This is very difficult to remove and does not contribute to the odor. Heavily soil areas sometime require multiple treatments to get it all. In addition, the enzymes sometimes need days to work. Make sure to check the walls as well. Many people have cleaned the floor and still had a slight odor. They found that the walls had been sprayed or urinated on as well.
Randy says
Only a couple walls had some urine on them, so that is not an issue. We did find that many of the baseboards had some urine and other smells on them, so we ended up putting vinegar on them and once it dried, we put Zinsser Bin Shellac Primer on the top, bottom, and sides of those baseboards. I will give it a couple of more days before reporting back the final result of this process.
Toni Choiniere says
With so many types of TSP, ie phosphate free and substitute, is there a brand that you would recommend? Is there something I should look out for when choosing? Is there a difference between the powder and the liquid?
Shea says
Hi Toni. Standard powdered TSP (P stands for phosphate) works best. If you are in a state that does not allow the use or sale of TSP, then you can use phosphate free TSP and mix some bleach in with it to kill the bacteria. Another product that will kill bacteria and help to remove stains is Borax.
Kelli says
Hello- thank you this is all really helpful! I do have a question re: if wanting to seal the concrete after cleaning with tsp and enzymatic cleaner to “prep the concrete first ie grinding or acid etching” — how do you prep it? Do you have steps for that?
Many thanks,
Kelli
Shea says
If you want to seal the surface with an epoxy coating, then it requires that you profile the concrete first via etching or grinding. We have an article here on acid etching and an article here on grinding.
Kelli says
Thanks so much! If needing to clean with tsp and the enzyme cleaner should that be done first and then do the etching or grinding or vice versa? Many thanks in advance!
Shea says
Hi Kelli. The grinding or etching is done first. The newly opened pores in the concrete allows the TSP and enzymatic cleaner to work more efficiently.
Kathi-Ann Rivard says
I appreciate all the info on your website but there’s so much, it’s a bit overwhelming. I have bare concrete in the house where carpet has been removed, and multiple cats with extracurricular peeing occurring. Prepping and cleaning in sections will not be a problem but applying epoxy/sealer all at once is just not an option for me. Is there an option that will seal the concrete but can be done in sections? I could clean and do a preliminary seal in small sections with the final, more aesthetic coat(s) done in larger sections later but in the end, it still has to be done in sections. The area involved is approximately 13 ft. by 26-ish ft. plus a hallway. Time span will probably be multiple weeks (maybe even longer) as this is not the only thing I have to do in my life. Is oil-based Kilz an option for a base? Epoxy-primer? What would be a viable finish/top coat(s)? Obviously, sun, oil, hot tires, etc. are not issues. I’m working on the inappropriate behavior but realistically, there will be ongoing recurrences. The final outcome does not have to qualify for House Beautiful. I just want to address the current odor, be able to deal with repeat performances with a mop, keep the cats and stay married. I realize I’m probably in unicorn and rainbow territory here but any advice, tips, suggestions would be greatly appreciated. Thank you so much for the care and effort you take to answer individual questions.
Shea says
Hello Kathi-Ann. Kilz is not compatible with epoxy. If you use it, you would have to apply an acrylic latex concrete paint over it. It’s not a durable solution and urine can get through paint with a little bit of time. Your best bet would be to purchase 2-part water-based epoxy kit. Rust-Oleum EpoxyShield is an example. You would need a 2.5 garage kit like this one here for your square footage. It will require that you use their Eco safe etching solution before applying the epoxy. We would recommend doing the entire floor with the etching solution first. This will open up the pores of the concrete at the surface and make cleaning with the TSP and enzymatic cleaner more efficient. Once a section is cleaned and has dried for 48 hours or so, you can then apply the epoxy over each section. The epoxy will seal the concrete and act as primer of sorts. You will have to pay attention to the mixing ratios of the part-A and part-B when you applying it in smaller batches. It will require cutting the corners of each pouch and pouring out the proper amount to mix. Either that or mix one batch together fully and do half of the entire floor at one time. Once the epoxy has cured, you can lightly sand the surface with 120 grit sandpaper and apply a nicer looking coating that comes in better colors for indoors. DuraGrade Concrete is an example. It has a nice glossy finish and will not be affected by the urine.
Kathi says
Thank you so much for your answer!! It helps a lot. Thanks for the links. My husband is an expert epoxy mixer (If you can’t fix it with JB-Weld, it can’t be fixed), so we should be able to mix in batches pretty well. One other question: The space under the baseboard where the carpet used to be is particularly gross because of the paneling and sheetrock. I can get it cleaned out but would like to fill it out flush with the baseboard so grime, hair, urine, etc. don’t habitate there anymore. I realize this is outside the realm of garage floor, but would the EpoxyShield adhere to say, tub and tile caulk or silicone or some other filler? I’d like to leave an option if someone ever wanted to put carpet back, but if mortar, concrete patch or the like is the only option, so be it.
Again, thank you so much for your info. You have lifted the weight of the world from me!! Blessings on ya’ll!!
Shea says
Hi Kathi. After you clean out and prep the area under the baseboard, run the epoxy and any subsequent coatings under it as well. Once the last coat is applied and cured, you can fill the gap with an appropriate sealant. Also, be sure to check the lower walls with a black light. It’s not uncommon to fix the floor problem and find that the odor is still lingering because the drywall was sprayed. If that is the case, you will need to cut out the offending areas and patch it up with new drywall.
Jane says
Hi what would you recommend for a commercial pet hotel concrete floor sealant? The urine smell is penetrating to other parts of the building. It was brand new construction just occupied a few months ago.
Shea says
Hi Jane. What you need is a non-breathable film forming coating such as epoxy or similar. Penetrating concrete sealants that are non film forming will not work. Urine that sits can still penetrate and smell after cleaning. Coatings will not allow the urine to pass through and can be completely removed from the surface.
Stephanie says
Thank you for this article! We bought a house that the previous owners dog had peed on the wood floors for several years and it soaked into the concrete subfloor. I followed your protocol exactly and all of the smells came up and we just had new flooring installed. I don’t smell a thing anymore!
Shea says
We are glad it worked well for you, Stephanie.
May says
Does this also remove smoke smells from garage floors (and walls if we apply these solutions on the wall as well)? What could be done about what we think is a combination smoke and pet smell left by previous tenants a couple of months ago?
Shea says
Hello May. We can’t tell you for sure if this will work for smoke smells in the concrete. For the walls, we recommend using a black light to see if any pets sprayed on the wall. If so, we recommend cutting out and replacing the drywall for those areas.
Tom Roling says
Will Zinsser odor blocking primer work instead of epoxy floor covering?
Shea says
Hi Tom. It might, but there is no guarantee. It works fairly well for some situations, but it’s still a paint that breathes and can allow odor molecules to pass through over time.
Tom says
what is the best epoxy that I can buy to coat the these floors. I need to cover about 1200 square feet, most garage floor kits are way less than that
Shea says
Hello Tom. The best epoxy is a commercial quality, 90-100% solids product. You won’t find it at your local home improvement center. All epoxy kits are only going to cover 250-300 square feet per batch. Epoxy is exothermic and can only be mixed in volumes of 1-1.5 gallons at a time. If mixed in a larger volume, it becomes too hot too quick and can’t be applied fast enough before it sets up. It can even begin to smoke from the heat before you are done mixing.
Tom says
Can you recommend a brand name of epoxy, and where to get it?
Shea says
Hi Tom. Where is the epoxy going to be applied and what do you want it to do for you? There are many types of epoxy, some give off VOC’s, some don’t, some are extremely durable, and some not as much. We can point you in the right direction once we know some details.
Tom says
It is going on a very stained concrete floor which smelled very bad in a house we just bought that has sitting for a year. I sanded all floors with sander with 12 grit, but that was not enough. I am now doing them all with a concrete grinder to get the black off. Next I will use the TSP cleaner, then the enzomatic cleaner. I bought Rocco and Roxies. Then I plan to seal it with epoxy. I just want to get the best I can get to make sure the smell does not come back
Shea says
Hi Tom. Being indoors, you will want to use a 100% solids epoxy since it does not have VOC’s to deal with. I’m assuming that you will cover the epoxy with some sort of flooring such as carpet or LVP? If so, there are a couple of choices we can recommend. The least expensive would be Rust-Oleum EpoxyShield Premium Clear Coating. We wouldn’t normally recommend EpoxyShield, but this one is 100% solids epoxy (their only one) and you will get a coverage rate of 200-250 square feet per kit. DO NOT USE the anti-slip media that comes with it. It has a tendency to clump and is no use anyways if covering with flooring.
The other option is RokRez Pro. You will get approximately 450 square feet per kit. It comes in colors as well if you don’t plan on covering it with flooring. They use a retarder that slows down the curing so that you have enough time to put down the larger batch. This is why the coverage rate is higher.
You may have already done this, but make sure to check the walls for urine and make sure to remove the base boards as well when cleaning with TSP and using the enzymatic cleaner.
Karen says
I am overwhelmed. I wonder if I can hire someone to do this as thoroughly as you have so clearly specified. I’m in Connecticut.
Shea says
I’m sure you could find someone, Karen. It isn’t that difficult to follow the steps and processes required.
Claire says
I just wanted to say that I used this method on our entire daylight basement after pulling up cat-urine soaked carpet and pad, and before laying down luxury vinyl plank about a year ago. It worked like a charm and the odor hasn’t come back over multiple seasons. Feral cats were coming in the cat door and marking territory, and home cats started doing their business in every corner and under beds, so I basically had to do the entire floor in 5 rooms. Thank you!!
Shea says
Hi Claire. That’s great to hear! The process works very well when all the steps are followed.
Joelle says
Hi. Did you use the wet/dry vac for getting up the water? I do not have one, but I have a carpet cleaner. Did you put any sealer down? . . . I’m so pissed because there was nothing wrong with this floor until we yanked up the carpet to LVP down and suddenly the cat decided it wanted to pee in there while waiting for a contractor to come put the floor in. It was already such a pain to clean up the tack and glue and dust, and now I gotta do all this?! Grrr….
Shea says
Hi Joelle. Our comments section does not work like a forum. Claire will not be notified of your question. A carpet cleaner will work fine for vacuuming up water and residue. Unless the cats were urinating on the concrete for a long time, the standard treatment that we outline most likely will take care of the issue. A non-breathable sealer would not be required.
Claire says
So, actually I did get a notice that my comment had a response 🙂
I used TSP in hot water to lightly scrub the area, let it sit about 30 minutes, then wet-vacced up any excess. Then poured boiling water to rinse and immediately wet-vacced it up. Repeated this twice for a total of three treatments. Let dry for 24 hours and liberally poured on the Roxy. Applied three times with 24 hour dry time in between. A long process, but easy, and even stains that had been there for months cleared up.
Virginia Nuta says
Hello–The litter box was in the unfinished portion of our basement. About half of that area was painted with concrete paint. After that, the cat became old and ill and you know what they do. She’s gone now. The smell seems to come (after it rains) not from the unpainted portion but rather from the painted portion. Does this mean I need to do something to the paint in order to be successful?
Shea says
Hi Virginia. Paint is not a sealer. What you are experiencing is urine that penetrated the paint to soak into the concrete below. When it rains, the concrete slab of the basement absorbs moisture from below it and activates the urine crystals. This is what causes the smell. It comes up through the paint. What you need to do is completely remove the paint and then treat the concrete as described in the article.
Virginia Nuta says
Thanks so much for the quick reply:
I guess this was kitty’s last rude gift; peeing in the spot that is more difficult to clean up. I’ve been using my black light and can’t see cat pee through the paint, but as that is where the smell is, I assume the paint is masking the phosphorus, would that be correct?
Thanks again.
Shea says
That’s correct. Don’t forget to check the walls in that area if you haven’t already.
John says
What garage floor sealers are you referring to in the article. Epoxy based? Could you recommend a brand that will keep residual odors out
Shea says
Hi John. Yes, epoxy is one example. There are others. Is this for an actual garage or some other area? If it’s a garage, how do you use it? We ask because not all garage floor coatings are of good quality.
Megan Jackson says
I am so impressed with your company’s responses to questions! I read the article and then read all the questions and comments. I feel like it can do this. I have already used TSP but was unaware I needed to do an additional step.
I have painted and stenciled my porch and patio and was hoping this method would work for my current concrete slab that I’m using as my den floor. After I treat it for urine smell I was planning on using (🐻 brand from the orange store) concrete and masonry primer, then porch and patio floor paint and finally top it off with a bunch of coats of water-based interior polyurethane… This method has worked well before, but those surfaces were not infiltrated with pet urine. Will this work to keep any future pee accidents from soaking in to the concrete? Or do I need to look into epoxy? Again, this is our den floor (previously etched and painted then carpeted, pulled carpet up and have scraped carpet foam glue up and lots of the precious paint), so lots of living happening in this room.
Thanks in advance!
Shea says
Hi Megan. If your goal is to completely seal the concrete, then you need to contact the manufacturer of the polyurethane you plan to use and ask if it’s breathable or allows moisture vapor to transfer through. Paint is breathable and will allow odor molecules to transfer through the paint. So it’s important that the polyurethane is not breathable in order to stop the odor. If it is breathable, then odors will make their way through. Epoxy, polyurea, and polyurethane (for concrete, not wood floors and furniture) typically are not breathable and will seal the concrete and not allow odors to pass through.
karen feeney says
Hello. Your article has been really helpful. We had a carpet that had been peed on multiple times. We removed carpet, used blacklight to find the stains, but decided to treat the whole basement floor with the vinegar solution and then with Rocco and Roxies. Left it on overnight and while we don’t smell the urine this morning, there is definitely a very strong odor. We have installers coming tomorrow to install LVP. I am concerned that this new smell will get ‘trapped’ under the LVP. Any information/suggestions would be really helpful. Thanks
Shea says
Hi Karen. Your concern is valid. Rocco and Roxie requires time to work. It’s an enzymatic cleaner that eats the uric acid crystals. You can’t apply it and then cover everything up a day and one half later. It requires a few days or more to work properly. We would highly suggest postponing install of any flooring until the odor is removed.
Karen Feeney says
Thanks so much for your quick reply. One more question – we rented two industrial fans to try to speed up “the process.” Should this help or just a waste of money?
Shea says
Hi Karen. The fans would only help speed up the process of drying out the concrete thoroughly. It’s very important that the concrete is dry on the surface as well as within the slab before you apply the Rocco and Roxie. They do not help with the Rocco and Roxie treatment.
Out of curiosity, did you receive an email from us that your comment was approved? We are having some bugs in our system and it would be helpful to know if you received an email or not.
Karen says
Hi Shea, I did get an email that the second message was approved, but did not for the first.
Regarding being dry, we did the vinegar treatment one night, mopped it up the next morning and then applied the Rocco and Roxie in the evening. So if you are thinking that the concrete did not have enough time to dry before we put on R and R, do you think that is why it smells? And what would you recommend at this point? (we are definitely putting off installing the LVP tomorrow)
Shea says
Yes, that can definitely be one of the reasons. We would recommend a second treatment of Rocco and Roxie. Enzymatic cleaners work best when the concrete is thoroughly dry.