Hi, I'm new here (been lurking a while but I think I can finally say something slightly intelligent) I have a Bull-Terrier who had the same problem i.e. peeing in the house. I discussed it with my vet and he said it could be the dog is marking territory, or suffering from low self-esteem i.e. his confidence has taken a battering, or simply that he couldn't get out when he wanted to go for a pee.
I'm glad to say it all seemed to be related to his habit of drinking gallons of water before he goes to sleep at night. I slowly weaned him off this habit and now he doesn't want to drink after 8 at night. I let him out to go have a pee at about 10, and he's back inside and ready for bed in 5 minutes flat. No more wet spots on the floor either
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Onegirl, it sounds to me like your dog is marking territory - I found an article that might give you a better insight - I won't hotlink you to it, but I'll leave the url so you can have a look.
www.goarticles.com/cgi-bin/showa.cgi?C=765519
Good luck