My dog stopped using his litter box

Question
I have a 10 lb male yorkie mix named Riley.  We trained Riley to use a litter box as a puppy (we live in an apartment).  He took to the litterbox very well from the start and never had an accident in the house.  Around the time he turned one he stayed with my sister for the weekend.  She also has a small male yorkie mix who uses a litterbox.  Her dog however was never fully trained due to her lack attention to it and supervision.  After that weekend, we noticed that Riley started peeing on hanging fabrics (curtains, bed skirts etc.).  We also noticed that for the first time he was going near his litter box but not always in it.  Well since then it has spiraled out of control and has gotten worse.  We have tried every technique in the book to get him to stop and we have taken him to several different vets to have him checked for any medical problems.   We keep his litter box in the laundry room and we keep it very clean.  He has now turned the whole laundry room into his litter box and will poop and pee anywhere in the laundry room but especially up against the walls and washer and dryer.  He only goes in the laundry room, never outside of it, and we have removed all hanging fabrics so that is no longer an issue. I am wondering if he is confused about the exact confines of his litter box and just thinks the whole room is his potty place?  The other thing is that when I am in the laundry room doing laundry he always comes in and goes right into the litter box and goes potty and then looks at me for a treat (which i give him) and he never pees or poops in the wrong spot in front of me.  I do admit that I am not that diligent about following him into the laundry room every time he goes in to supervise him, but it's almost like he knows where I want him to go but just doesn't always go there unless I'm watching.  We are planning on moving this summer and I am thinking about retraining him to go potty outside so he knows indoors is off limits.  It seems to me that he just doesn't understand exactly where his litterbox ends and the "no potty zone" begins. He is a very good dog, I have a hard time getting mad at him b/c I don't think he means to do bad things.  We have a baby on the way and I know cleaning poop and pee off our laundry room floor everyday will just not fit into the equation once the baby arrives.  Do you think its possible to retrain him to go potty only outside and that everywhere inside is off limits?  He will be three this June.  Thank you.

Answer
No he doesn't mean to do bad things,. he's just developed a habit. Dogs don't intentionally do anything bad. Regardless of what humans may think :). You can definitely train him to go outside to potty, but in doing so you will have to remove his litter box completely and put him on a crate training schedule. Put his litterbox outside and everytime you take him out, show him the litterbox and give him a command, go potty or whatever. LOTS of rewards for success IGNORE the failures completely , just clean them up. Your house needs to be VERY clean of urine stains and odors and he needs to be crated while training.
You can do this!
Cindi