cat urine odor

Question
WITH OUR RECENT BOUT OF FREEZING TEMPS. UPON SEEING BLEEDING PAWS AND HEARING THEIR CRIES I DECIDED TO LET THE WILD CATS LIVING AROUND MY HOUSE IN THE GARAGE FOR ONE NIGHT. NEXT MORNING AFTER THEY LEFT THROUGH AN OPEN DOOR IT WAS VERY APPARENT I NEEDED TO TAKE CARE OF THE OVERPOWERING SMELL OF CAT URINE, EVEN MY CAR SMELLS.  I WASHED DOWN THE FLOOR WITH PURE AMONIA BUT IT DIDN'T HELP.  ANY IDEAS?
THANKS,
LORI  

Answer
Thank you for reaching out to these guys.  The elements are the second leading cause of death in outdoor cats, second only to disease.

Unfortunately, ammonia doesn't generally work to remove cat urine odor.  It actually worsens it in many cases, because cat urine is high in ammonia itself.  The best way to remove cat urine odor is to use a cleaner the contains enzymes.  Anything with citrus oil contains enzymes, and there are cleaners available at pet stores that are enzyme-based.  Nature's Miracle is a good one.  The enzymes in these cleaners break down the fat molecules in cat urine that make the odors cling to strongly.  You may need to repeat the treatment once or twice, but it should hopefully help.  Sometimes if the area the sprayed is porous, like unsealed cement, the odor will be very difficult to remove.

Not sure how you feel about this, but if you decided you'd like to make a winter shelter for the cats, here are some ideas.

http://www.pacthumanesociety.org/core/WinterShelter.htm  

The shelters are very small, generally built out of a small storage container, and quite a few kitties can pile into one.