many homes have a small cold room in the basement underneath the concrete front steps, but these rarely work well for food storage, despite their name. freezing temperatures and frost on the walls during winter, and too-high temperatures in the summer make for spoiled food and even mold growth. so is there any hope for a standard basement cold room? yes, but upgrades are almost always needed first. and even then, performance can never be as good as with a full basement cellar or a stand-alone root house design.
the problem with so many cold rooms is insufficient soil cover around the structure. the solution is to add 2”-thick sheets of closed cell foam insulation to the ceiling of a cold room and part way down the walls. extend this wall insulation so it’s 12” below the level of soil outside. extruded polystyrene foam is a good option for this, covering the foam after installation with cement board or mold-proof drywall. this foam needs to be sealed to the wall along all edges using caulking or spray foam. this prevents indoor air from getting behind the foam and condensing during winter. whatever you do, never use the white, beady expanded polystyrene foam insulation in a cold room. air can pass right through this type of foam, allowing condensation to occur underneath.
root cellars used to be a necessity of pioneer life, but modern homeowners are discovering them again, saving money, eating better and enjoying a new independence from the grocery store. try root cellaring in your own life and you’ll probably never want to be without it again.