My dog keeps peeing and pooping in the house?

It sounds like your dog doesn't like your new house. It's not uncommon when you change homes. First have a vet give him a check up to make sure he doesn't have something wrong. Then I suggest when you do let him out go with him until he has gone. 15 minutes isn't long enough. Only feed him once a day, dog food only. Dogs should not be given people food. Take him out after you feed him to let him run and work the food through his system, also at minimum late at night and early morning. When he does go while outside give him a treat. If he doesn't, no treat. Animals learn by positive actions. To get rid of any odor left from his accidents put white vinegar with water in a spray bottle and spray where he went. The smell will be gone within 15 minutes and if he smells it next time he won't go in the same place. It won't harm floors or carpets so don't worry.