A method of forming a passageway in an insulated door of a refrigerator includes the steps of forming a conduit by inserting a mandrel in the space between a door liner and outer skin, filling the space with foam insulation, and removing the mandrel. In one embodiment, the mandrel is encased with a polymeric skin prior to the inserting step, such that, when the mandrel is removed, the skin remains at the boundary of the passageway so formed. In another embodiment, the method includes mounting fluid and/or electrical conduits to an inside surface of the door liner and subsequently injecting the foam insulation to surround the conduits. In yet another embodiment, fluid and/or electrical conduits are mounted to an outer surface of the door liner. A cover is then positioned over the conduits.