going to the bathroom in the house

Question
I got a 9yr old lab mix, very well trained dog. He is house broken and get lots of outside time. In the last few weeks he has been going number 1 an 2 on my carpet. I will walk him and he will go more then once, then I will leave the house anywhere from 10 to 30 minutes and he will go on the floor. I give him lots of praise when I return if he didnt leave me a surprize. I will take him to a local dog park to play. I just moved to this place and I go to school at nights. I just broke him of the barking while I am away and now its this problem. How do I go about breaking him of this? thank you Phil =)

Answer
Sometimes, when a dog's living situation changes, his house training skills regress.  So, go back to training him just as you did when he was little, and this should get better quickly.  Because he is nine, I would also have him checked over by the vet, since this is a sudden change in his behavior.