Crawlspace as Root Cellar
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I am in the process of building an addition to my house, the foundation is a concrete ringwall insulated on the inside with rigid insulation. I will have a +/- 4′ conditioned crawl space, and I would like to have a place to keep vegetables and canned goods. I am in zone 7a, so the mean temperature of the ground 4′ down will be quite cool.
I am envisioning an enclosed, insulated space in the crawl. But I am unsure about ventilation, should it be passive or active? I will have an HRV with both supply and return in the crawl.
My grandparents had a huge root cellar on the farm, I remember picking an entire acre (!) of potatoes on Thanksgiving weekend with the extended family and placing them in the huge root cellar. There were enough potatoes, turnips, carrots, etc. down there to feed a large group of people for an entire year. Pretty cool.
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Replies
plumb_bob,
Rather than build in part of the house with competing temperature and humidity goals, maybe it makes more sense to do as David did and build it as a separate structure?
https://www.greenbuildingadvisor.com/article/flatrock-passive-thoughts-on-a-winter-greenhouse
Well, because I have approximately 10 years of projects lined up in front of me and dont want to add another! Also, my property is getting maxed out for coverage as per zoning.
I guess the question really is whether the heat and humidity requirements are competing, and if they are, how hard it would be to create a micro climate in the crawl. Temp should be easy with a space insulated form the conditioned air.
I have an old book on root cellars at home, I will dig it up and do some research.
A lot of root cellar designs show passive ventilation, which probably works fine as long as the weather cooperates, but I would consider investing in a CoolBot device so you can fine-tune the temperature. That gives you control at a pretty affordable price.
I would also provide a bit of fresh air, as fruits and vegetables give off ethylene gas as they ripen, which hastens ripening of the other items in your cellar.
@michael_Maines - that CoolBot is interesting. Had never heard of them.
Does anyone know of any device that would provide root cellar type temp & humidity function but that is only about the size of a cooler?
I am contemplating a root cellar in our detached garage at the farm. It was a great garden year and we have a big crop of Red Norland potatoes that I want to keep along with the small ones for next year's seed. It will basically be an insulated box (R-20) using expanded polystyrene or possibly some recycled extruded. Will provide an air space around the storage bin and plan to heat with a resistance mat and a line volt mechanical thermostat. Will aim for 40F. Good luck fellow gardener.
Will you be ventilating? Passive or active?