Several times a week our neutered 8 yr old male cat pees in our carpeted hallway. He has a cat flap, we've had him checked out by vets more than once. Tried feliway. There are stair gates so he can escape the dogs and kids to the top floor. Nothing has made any difference. My whole downstairs smells of cat pee. I get through a lot of pet spray but it still reeks. We borrow a vax periodically but not sure it helps.
We have had him since a kitten and our lives have changed alot and to be honest I think he preferred our lives before they arrived! It's getting me down as I love him but I don't like him much any more. That's a horrible thing to say, I know. He's never been a cuddly cat, and we rescued him from a 'animal hoarder' at about 10 weeks. So I know damage can be done by then 
Is he peeing because he's unhappy here? How do we make him happier? Any magic tricks to deal with cat pee smell?
Help!