I have an 11 month old male shih-tzu x maltese poodle, not desexed. He was house trained until about 3 weeks ago when my boyfriend went away for work for 2 weeks.
He started urinating around the house, usually aiming for clothes baskets, suitcases, the couch etc. despite the back door being wide open. I suspected he was marking his territory and hoped it would stop when my boyfriend came home, but it didn't.
When he does it I take him to the spot, tell him "bad dog", give him a light smack on the nose and send him outside and ignore him for a few hours.
Please help, I really want to put a stop to this before it becomes normal behaviour.