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Q: Remove Cat Urine from Concrete Floors ( No Answer,   4 Comments )
Subject: Remove Cat Urine from Concrete Floors
Category: Family and Home > Home
Asked by: monsterthecat-ga
List Price: $52.00
Posted: 18 Sep 2004 16:07 PDT
Expires: 18 Oct 2004 16:07 PDT
Question ID: 403023
Yes, this is a horror story, stop here if you have a weak stomach.  My
sister-in-law lived in a house for eight years with approximately 40
cats and she was a smoker.  The house was the cats' liter box.   I
have thrown away everything, all furiture, appliances, kitchen
cabinets, and removed the vinyl flooring with a shovel.  The house is
empty.  The house has been powerwashed with just water (starting with
the ceiling and working down to the floor).   The power washing helped
alot but the smell of cat urine is still present.  The house was built
on an 18 inch thick concrete slab (unsealed) The house is
approximately 1,100 square feet in size.   The walls are covered with
painted drywall with the main room walls covered with wood paneling.  
Prior to the powerwashing a blacklight inspection revealed urine on
the lower 2-4 feet of the walls.  I am looking for an answer to remove
the cat urine smell from the concrete floors and walls.  Is there a
brave chemist or equally brave professional out there with a serious
answer?  Is replacing the bottom 2-4 feet of the walls and associated
insulation part of the answer? (Gasoline and a match is not a
solution, my father-in-law built this house and it holds great
sentimental value to my husband and mother-in-law.)

Request for Question Clarification by techtor-ga on 19 Sep 2004 08:54 PDT
Hello Monsterthecat,
If removing the source of the urine smell is difficuult, have you
instead considered trying products that can mask the smell? For
example, an ozone generator?

Clarification of Question by monsterthecat-ga on 19 Sep 2004 14:16 PDT
Thank you for your request for clarification.  By "mask the smell",
did you  mean that you have a no-fail sealing method for the concrete
floor?  Otherwise, I am not looking for a deodorant or perfume unless
there is  sound scientific evidence that this method is a
professionally accepted standard and that it works.  A final solution
resulting in a 'cat urine plus whatever odor' is not acceptable.

Isn't there a nice chemist or chemical engineer out there who can help
with this "let's examine this problem at a molecular level and break
the molecular bonds of the odor producing volatile organic compounds,
proteins, etc., " solution?

Clarification of Question by monsterthecat-ga on 19 Sep 2004 14:21 PDT
PS:  The difficulty factor is not an issue.  We already dug a treach
with a bulldozer just to bury the cat urine saturated furiture,
flooring, appliances, etc., in 100 degree weather.  Anything less than
that wouldn't be too bad.

Request for Question Clarification by bobbie7-ga on 19 Sep 2004 14:28 PDT
Hello Monsterthe cat,

Mark, an  IICRC Certified Master Cleaning Technician and IICRC
Certified Master Restoration Technician  posted some useful
information and advice regarding the removal of strong cat urine
Read about it here:

Does this help?


Clarification of Question by monsterthecat-ga on 20 Sep 2004 11:37 PDT
Yes, this way helpful.  Is the final portion of the solution, i.e.,
sealing the concrete, an absolute requirement?   Can't all the urine
be neutralized chemically   Thank you.

Request for Question Clarification by bobbie7-ga on 20 Sep 2004 13:01 PDT
Is the final portion of the solution, i.e., sealing the concrete, an
absolute requirement?

Yes, I believe that sealing would be the only solution.

According to Mark, the  IICRC specialist that I cited previously, a
cat urinating just 6 ounces per day is 17 gallons of urine per year.
Your sister-in-law lived with 40 cats for eight years. That would be
over 5000 gallons of urine.

He says that ?Enzymes can work, but in situations of strong odor, they
*never* will.?

He goes on to say: ?you cannot remove dried urine from *porous*
surfaces like wood and cement. You must *seal* the unremovable urine
in thecontaminated surfaces. It must be sealed from *exposure* to heat
andmoisture. If warm, moist air does not contact the dried urine
crystals, youwill NOT smell the urine.?

I see no other solution to this problem.

Would you need additional information?


Request for Question Clarification by feilong-ga on 01 Oct 2004 06:49 PDT

Perhaps the simple chemical solution you're loking for is pure,
undiluted bleach such as Chlorox. I've effectively used bleach for
just about every source of foul odor in our house -- from left behind
food odors and animal odors which includes dead rat odor. Try it if
possible and see if it works. Please let us know the result.

There is no answer at this time.

Subject: Re: Remove Cat Urine from Concrete Floors
From: pinkfreud-ga on 19 Sep 2004 14:52 PDT
There are several products that use enzyme activity and/or
chemisorption to remove cat urine odors.
Subject: re: painted drywall
From: daytrader_7__6-ga on 19 Sep 2004 17:21 PDT
I'm more carpenter than chemist, but *urine luck* because I have done
a similar drywall job repairing flood damage.  Getting the old drywall
off is the easy part.  A hammer will go right through it :)

You can patch the part that you remove with drywall, or some houses
have the lower  half of the walls done in paneling, which would be an
easy fix for you.  You may also patch it with drywall.  If it is
smoothly finished, the seam might show a little.  Use the paper tape
for the seam, not the new fiberglass mesh stuff.  If it is textured
finish, you can re-apply a texture with a brush or broom dipped in
topping compound (drywall mud - the brand I use has a blue lid instead
of a green).  If it is important to have a seamless new wall, you may
also just rip all the old drywall off and start over.

Remember to wear eye protection.  Gypsum in the eye is no fun.
Subject: Re: Remove Cat Urine from Concrete Floors
From: morrissette-ga on 01 Oct 2004 06:33 PDT
Hi, I have a treatment that is miraculous. I have six cats, the house
we moved into had been used as a litter box for the previous tenants
cats and dogs. Needless to say, my cats thought the same, by the smell
of it, and proceeded to do the same. Anyhow, since we couldn't tear up
the flooring and remove the carpet, I had to find something to get rid
of the smell. I found this recipe/remedy on the internet: 1 quart
hydrogen peroxide, 1/3 cup baking soda, and a dash of liquid soap;
wait about five minutes until the baking soda dissolves, pour it on
the offending matter and let it foam. Leave it there until it's dry,
mop up the residue and your done. I swear to you this works! I have
tried gallons of Nature's Miracle (a popular enzyme cleaner for
urine), and it didn't do a thing. If you wait for a sale you can get
hydrogen peroxide by the quart for .99 cents. Don't even waste your
money on enzyme cleaners. Good luck, Mollie
Subject: Re: Remove Cat Urine from Concrete Floors
From: cdeeds91375-ga on 25 Oct 2004 04:49 PDT
I had the same problem here at my house and it was quite a large task,
but it can be done. Most answers here are already right, but the one
that is completely true is enzyme cleaners don't appear to touch the
I have a B.S. in Chemistry and Biology and took a look through some
old texts and found that you could use some kind of odor neutralizer,
but without re-sealing the concrete, removing & replacing the 
sheetrock on the bottom portion of the walls, even sealing the wood
behind the sheetrock (with a couple coats of shellac or something
This will help and it will get rid of the odor.
Any questions please email me

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