I have several cats and just moved to a new house. One of my neutered males has sprayed the carpet on our stairs several times. I used oxyclean and other products specifically for this purpose but the only thing that really worked was a product I found advertised in the back of Cat Fancy Magazine. I'm not sure if it will work on wood floors but you could check out their website. It is www.pureayre.com. I think it is a great product and worth a try. It does have a 100% money back guarantee. I hope this helps. You really have to get the odor removed completely for him to stay away. You may want to try the Feliway products as well to keep him from doing it. I have just put moth balls in a bowl in the area for now to keep him away and it has worked. It is just a temporary solution though. Good luck.