Hi -

I think a lot of the answers to your questions depend on what you'd like to store. The house in which I was raised had a cold storage room in the basement, but we used it primarily for canned goods. If that's what you're thinking of doing, then I don't imagine you need any special ventilation. If, on the other hand, you're planning to store any true perishables, you might be better off in the long run considering something like a small walk-in. Nor-Lake makes a line of these that seem pretty easy to assemble, with an easily-accessible external condenser unit and a fan to keep the air moving - I'm including a link.

Here is a link that might be useful: Nor-Lake Step-In Cooler

Thanks, HomeSweetHome. We will store canned goods, inexpensive wine, and apples and potatoes. So, a mix of perishable, and somewhat perishable.

We're trying to build an eco-friendly house. So a walk in fridge doesn't really fit with that idea.

Hmmm...what are you planning to use as your heating system? If you're going with something like geothermal, maybe there's a way to cool the room with the ground water before it gets to the heat pump? If you installed radiant coils in the floor of the storage room on the way to the heat pump, I imagine that would keep things pretty regular no matter what the weather outside was doing.

As for air circulation, I don't think it would be necessary for you to vent to the outside, particularly if you live in a dry climate. An opening to a larger source of air in the basement and a small fan should be plenty. Sounds as though you'll be using this pretty much the same way we used ours - as a cool pantry. Provided you don't need to maintain any single consistent temp, a set-up like this should keep things cool enough.

Both potatoes and apples need about 90% relative humidity for long term cold storage. And adequate air circulation is important. Apples prefer to be kept in the lower 30s. Potatoes in lower 40s.