To continue the posts about using the garage as cold storage in the winter, we do this (we refer to it as “the walk-in freezer”). Like wolfpup ours is adjacent to interior walls/floors on three sides, but I also have a small cube heater on a shelf at waist height, plugged into a thermostatically controlled adapter plug set to 5ºC. I got it at a farm supply store, but they can likely be found at hardware stores as well. It keeps the temperature above freezing.