Our cat was using a corner of our landing which is carpeted for peeing and we did not notice for ages....until the smell. That was nearly two years ago. During the winter months we dont get a smell but now that the summer is here, you can get the smell when u go upstairs. We cannot afford to replace the carpet as it is an expensive one....it has been washed by professionals, soda powder etc....the smell is still there....has anyone any other ideas....ta!!
Get rid of the cat! Seriously though if you have tried the professional services not much else you can do. did you try hiring a carpet cleaner from a plant hire and trying to clean it yourself? If this doesn't work would replace the carpet or remove it at least until you can repalce it. Nothing worse than the smell of pee!
Washing the carpet will not get rid of the smell. You need to treat the area with a chemical product that breaks down the component in cat urine that causes the smell. There are many products available on the market. I can recommend Urine-Off. www.urine-off.com
Also if your cat has been peeing around the house, it is usually a sign that your cat is stressed or unhappy. You may need to look at your litter box arrangements. (location, regular cleaning, type of litter material, etc.)
i used this stuff when my cat peed all over my bed, and was really impressed with the result. You spray it on, leave it for a few minutes, and then blot up all the moisture with a clean towel. If its an old stain you may need a couple of applications, but the only smell left in the mattress was a fresh baby powder smell.
Not sure about stockists in ROI, but you could probably get it in most large petstores.
On top of the good advice above. Did you make sure that the professionals got to the root of the problem. If the cat was peeing in the same spot for ages then it's likely that the underlay and maybe the boards were also compromised. Lift up the carpet (it's in a corner, right) and see if you can replace the underlay in the area entirely also try under the carpet, usually those cleaners don't do a right through job.
You did not say if the cat had stopped doing this. If not get cat flap, cats by nature are not dirty and will do anything to hide their mess hence the out of the way place. I think you said just in one place rather than all over the house which would suggest the cat does not get out enough.