Is it your house or do you rent? If you rent, is he on the lease? If the house is owned in your name only, or the lease is in your name only, just change the locks. If his name is on the lease, ask the landlord if you can get him off the lease.
You should not have to live with a crack addict alcoholic and you are under NO obligation to continue supporting him. Children should NEVER live with a crack addict or alcoholic.