Male Dog Urinating in the House?

My 7 year old Yorkie has recently started urinating in the house at night. About 6 months ago a number of changes took place in he house - we got 2 kittens and new furniture. He has only started doing this about 3 months ago though. There is access to the outside during the night - a hole in the door.

He does go out, but when I get up in the morning I often find a piddle under the coffee table and more recently under the couch. What can I do as my house is starting to get a smell now. I wash the piddle off as soon as I see it with pet odor remover.

By Toni R