JUST replaced our carpet. The main reason we did so is because the cat I have had for 15 plus years had decided to us it as her litter box. I couldn't send her to the pound, so when I can't watch her, she is locked in a room with a litter box. (I know this sounds cruel, but it is a rather big room. Much bigger than a cage would be.)
The other day, I was fixing dinner and she was... somewhere. I walked into the living room and there. on my floor. was cat poop. I was furious. I picked her up (she was on the couch) and walked outside. I [gently] set her down and walked away. Now, every morning I bring her outside, (to our fenced in backyard) and every night I bring her inside and put her in her room. I searched and searched and searched for a way to get the smell out. Because we just replaced the carpet and I am not doing it again. I found this recipe and it works! I was soooooo excited. :)
16 oz hydrogen peroxide
1 teaspoon dish washing liquid (I use Dawn)
1 tablespoon baking soda
Combine all ingredients in a spray bottle. Soak the offending area. Let dry. (You may need to vacuum a white foam away once the area has dried) The smell should be gone!
This totally works for me!!