ADAS 2010 604.2 Water Closet Location
The water closet shall be positioned with a wall or partition to the rear and to one side. The centerline of the water closet shall be 16 inches minimum to 18 inches maximum from the side wall or partition, except that the water closet shall be 17 inches minimum and 19 inches maximum from the side wall or partition in the ambulatory accessible toilet compartment specified in 604.8.2. Water closets shall be arranged for a left-hand or right-hand approach.
Code according to 2010 ADAS. Check your state’s accessibility laws. Some states such as California, Georgia and Florida have additional requirements and standards.