Matt:

You are not the first person that this has happened to. Prior to getting a heated garage, the VP of the last EMS company I worked for decided that he had to have a shiny ride in the middle of the winter. As with your crew we had access to an indoor wash facility. So the boss washed his rig and went out to a staging point in the city. About an hour later the doors (not the locks) were frozen shut. He and his partner had to kick the doors open to get out. Luckily they were only at Dunkin Donuts and not on a call.

Chris