Root Cellar with Super-Insulated Structures?
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I’ve been working on Passivhaus designs in a cold/ very cold climates. Our clients have been interested in root cellars. My understanding is that a root cellar depends on heat being lost from the house. If we put a root cellar outside a highly insulated envelope and provide some ventilation to evacuate the gasses ripening veggies give off then the temperatures will reach the outdoor temperature unless we add heat.
Is it worth doing a root cellar at this point? Or can you design a room that can get by with the heat of an incandescent light bulb for instance where this still represents a better approach than using the refrigerator?
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A root cellar works because it's a cellar - under the ground but outside the thermal envelope - so minimal heat and minimal ventilation will suffice. But make sure you understand the parameters required for it to function.
I lived with a root cellar for three years. In my experience, when the smell was strong enough to need venting that was a sure sign we weren't eating things quickly enough or had not let in enough winter air. Our cellar had only latent heat from the earth and no intentional venting. Seemed to work great. We used wood shelves, wood boxes, and lots of straw for packing.
Its temp was a bit too high for dairy products or meat storage so we had to have a fridge (and in any case, the cellar was a long way from the kitchen). I think of a root cellar as a good place for longterm storage of things that are not particularly fragile. They aren't a substitute for an icebox, whether you cool it with your own blocks cut from the ice for summer use or plugging into an outlet (hopefully clean-energy powered).
If this will be a large cellar, then consider how the truck will pull up, and how you will physically pass fresh items down and rotten items back out again. Straight stairs beat angled stairs! Fewer people needed on the veggie-toss line. Our record loading day was 3 tons of squash, 2 tons of which later came back up again for the food bank. You wanna make that kind of thing as easy as possible.
J Chesnut,
If you live in a cold climate, you are lucky -- your cellar will work better than a cellar in a mixed or hot climate.
Right now, the dirt-floored cellar in the house where I live in Vermont is full of potatoes, beets, carrots, and cabbage. The cabbages were harvested roots and all, and they were replanted in the dirt floor of the cellar. They will stay alive and delicious until May, without any light.
If you build your root cellar with attention to air tightness, it shouldn't get too cold, as long as it is mostly below grade. In my area of Vermont, the challenge faced by my friends and me is keeping our cellars above freezing; we generally don't have to worry about the cellar getting too warm, from October to late April.
If your cellar is part of your house, having a water heater or furnace in the basement can be an advantage (by ensuring that the cellar never freezes) or a disadvantage (if you forget to build an insulated wall between your appliances and your vegetables, resulting in a room that is too warm).
In my case, I have a cellar with no heating appliances at all. By careful attention to air sealing, I manage to keep the temperature at 32.5°F or above.
When building my house, I considered installing a dumbwaiter, built so that the dumbwaiter was in a shaft below the kitchen counter. The normal position for the dumbwaiter would be in the cellar, where it would act as a refrigerator. At any point, the dumbwaiter could be cranked up to the height of the kitchen floor, and I could open the cabinet door to get my butter and milk. I never built it, but I know it would work. Another six-digit idea that I never capitalized on.
Now there's a good idea.
That's neat, Martin.... what's the annual max temp in your root cellar?
"I considered installing a dumbwaiter, built so that the dumbwaiter was in a shaft below the kitchen counter. The normal position for the dumbwaiter would be in the cellar, where it would act as a refrigerator."
If you ever build it, post a video on YouTube!
My cellar stays at refrigerator temperature (32.5 °F to 40 °F) from late October to the end of April. By August, it's probably up to 50°F or 55°F, but I don't pay much attention in the summer, because my vegetables are in the garden at that time of year.
Martin this is an excellent thread and a worthy topic for its own Blog spot. I hope you do such. Fantastic info for someone like me who is slowly getting into veggie gardening a large enough crop to store. And what the hey, let's start a thread on canning and smoking and other preservation methods. Useful green advice greenies, thanks.
Martin,
A dumbwaiter shaft from your refrigerator-cold cellar to your kitchen cabinets would have to be pretty well insulated and sealed, including the cabinet door, to keep from chilling your toes or risking freezing of your pipes, and it may require fire-stopping since it connects floors.
Maybe that's why they called it "dumb".
Robert,
Yup, that's what I had in mind. Rigid foam around the part of the shaft that penetrates the kitchen, and a carefully made cabinet door with full weatherstripping.
Martin I hope you are putting some of that cabbage to good use by making kimchi : )
From what I have read about root cellar fresh air circulation was emphasized in order to evacuate the ethylene gas given off by the ripening produce. But from what I am gathering in the comments here is that when it is really cold you can stop ventilating and make the root cellar air tight in order to keep the air temps from dropping below freezing. Again I'm talking about circumstances that don't have the benefit of incidental heat loss from a conditioned space that can help keep temperatures above freezing.
To you guys in Ole' New England any examples of homes with larders lingering?
J Chesnut,
I think that the concern about ventilation only arises when the root cellar is very small. My cellar is 16' by 24', and odor has never been a problem. The only ventilation happens in October, when I open a couple of vents for two weeks to cool off the cellar for the season.
I used to make huge amounts of kimchi, which of course requires Chinese cabbage. (European kimchi is called sauerkraut -- basically the same process, but without the garlic and hot pepper.) These days I buy my kimchi in jars at an Asian market when I can find it; unfortunately it's not widely available in Northeast Vermont. Your reminder makes me salivate; next year I really should make 10 or 20 gallons of kimchi.
One good, fairly passive design is to install two vent pipes leading to the outdoors. 4" PVC would work. One pipe terminates close to the floor; the other terminates close to the ceiling.
In the fall or whenever you need to cool the root cellar down you open the vents and warm air exits at the top while cool air comes in at the bottom. Once the root cellar is at the temperature you want, close the vents. Keep a remote temperature sensor down there so you know when it needs attention. Keep a tray of water on the floor to provide humidity. The temperature will be cooler near the floor so keep vegetables that need it cooler closer to the floor. Or keep the vegetables in lidded plastic containers which will conserve moisture and the chance that ethylene gas will cause accelerated ripening.
Another option for a root cellar is to dig a hole outdoors, bury a large trash can, fill with vegetables layered with clean straw, and cap with the trash can lid and bales of straw or hay. Not as convenient as an in-house root cellar but the idea is to keep the vegetables in something close to their natural environment, in the ground....
One other idea is to "clamp" potatoes or other root vegetables. Place them in a pile outdoors and cover them with straw and a layer of dirt.
Interesting sidenote, although in the US Kimchi is always made with cabbage, in Korea it includes any fermented vegetable.
For more information check out this article: http://www.mofga.org/Publications/MaineOrganicFarmerGardener/Fall2008/RootCellars/tabid/984/Default.aspx, or this book: http://www.amazon.com/Root-Cellaring-Natural-Storage-Vegetables/dp/0882667033.
Michael,
When I made kimchi, I added white Daikon radishes. You're right -- you can add almost any vegetables you want.
However, I want to strongly disagree with your advice to put vegetables in a plastic container with a lid. Don't do it! The vegetables will soon rot. (I know a neighbor who put his entire carrot crop in sheetrock compound buckets. All his carrots rotted.)
I pack my carrots and beets in clean sawdust and store them in cedar boxes. You can also layer your carrots and beets in dry autumn leaves. No plastic!
Potatoes do fine in a wooden box without sawdust or leaves.
Martin... your "healthy vegetable advice" sounds very much like Robert's "healthy house" advice.
John,
It's only a matter of time before someone shows up and points out that "carrots gotta breathe."
10,9,8,7............
Martin, I only know the Kimchi trivia because a friend happened to live in Korea for a while. I haven't made it myself...yet. I'm ordering Daikon seeds soon but hadn't thought of fermenting the root when it's ready--good idea.
I wouldn't have believed the plastic bin theory either if Cheryl Wixon hadn't recommended it. She is licensed engineer, former chef, and now works for MOFGA (Maine Organic Farmer's and Gardener's Association). I attended a talk she gave on root cellering, and that's how she does it. She checks on the vegetables regularly and uses the ugly ones first, which probably helps a lot. Her root cellar is dryer than ideal, as I recall, so the plastic bins were a way to make up for that shortcoming.
The sawdust technique isn't foolproof either. My father in law stored his carrots in sawdust this year (granted, in sheetrock buckets, but without a loose-fitting lid) and they quickly rotted. I just dug the last of my carrots from the ground last weekend, but with a thick covering of straw they would have lasted a while longer.
Michael,
The problem with your father-in-law's carrots is the sheetrock bucket, not the sawdust.
My method has worked for me for 35 years. Now we have two anecdotes of rotten vegetables stored in sheetrock buckets -- from my neighbor and your father-in-law.
I'm glad it works for Cheryl Wixon, but the storage method is too risky for me.
6,5,4,3,2,1...
CARROTS GOTTA BREATHE!
Biological entities can no more live in a plastic bucket than humans can live in a plastic house.
But I like the answer given by Stephen Gaskin, founder (and head guru) of The Farm in TN, the most successful and longest-lived commune in the US of A, when asked why he prefers eating vegetables to eating animals when even carrots have feelings.
He said, "I've been to corn-shuckin's and pig-stickin's and the vibes are better at the corn shuckin's." But, then again, I met him when he came with his entourage in a big rock-n-roll tour bus to Seabrook in 1978 to join in the planned occupation of the nuclear power plant construction site. When we patiently explained to him why it was necessary to make a last minute change from civil disobedience to a legal rally, he decided to leave, saying "The vibes here are f*cked." Maybe that was because our command post was set up in a chicken coop and he thought the smell was because we were all full of sh*t. So much for vegetarian "good vibe" gurus!
BUT IT'S STILL TRUE THAT CARROTS HAVE FEELINGS AND THEY HAVE TO BREATHE!
Speaking of Stephen Gaskin (as opposed to air tight gaskets)...
I just learned that, in an informal rating of the Guru Quotient (GQ) by a simple 15-question test, Gaskin came out at the top of the pack (70 or better is a good score):
Out of a potential 100
- Bhagwan (Osho) 17
- Maharishi 23
- Leonard Orr of the Rebirthing movement 53
- Swami Bhaktivedanta of the Hare Krishna movement 60
- Krishnamurti 73
- Stephen Gaskin (from the Tennessee farm commune) 77
And, speaking of ROOTS...
I also just learned that my old nemesis, Stephen Gaskin, was the recipient of the first Right Livelihood Award in 1980, for his private "peace corps" called PLENTY, which - among other things (see below) helped rebuild 1200 homes and lay 27 kilometers of waterpipe in the Guatemalan highlands after the 1976 earthquake.
PLENTY is an international, non-profit, non-sectarian agency for relief, development, environment, education and human rights. It was founded in 1974 by Stephen Gaskin on the principle that all people are members of the human family and that, if we protect and share the abundance of the earth, there is plenty for everyone.
From 1976 until the end of 1980, PLENTY employed more than 100 American volunteers in projects with the Mayan people of Guatemala - in fields such as primary health care, drinking water systems, soya bean agriculture, food processing and communications technology.
While working with the Mayans in Guatemala, PLENTY gave priority to the strengthening and preservation of indigenous cultures. "We learned to that an amazing degree we shared the values and visions of these precious cultures and that, for us, development was no longer a one-way trip in which we, the privileged, provided help to the underprivileged. We saw that, in truth, it was a fair exchange where every participant had something valuable to give."
In 1978 the PLENTY Ambulance Service was established in the South Bronx, New York, providing free emergency medical care and training to the embattled residents of that sprawling American ghetto. In the same year, a rural village development programme was begun in tiny Lesotho, a country landlocked by South Africa. Then, early in the 1980s, PLENTY founded a free health clinic for Central American refugees in Washington, DC, and undertook small-scale agriculture projects in Jamaica, St Lucia and Dominica in the Caribbean.
PLENTY donated an ambulance in the early 1980s to the Akwesasne Mohawk Reservation in upstate New York. Two Farmies - one a paramedic and one an EMT - taught a licensed Emergency Medical Technician course to 22 reservation residents, helping them set up their first Mohawk-run EMT service.
PLENTY maintains an office in Belize, Central America, which initiated a school lunch program based on organic gardens planted next to each school to help provide more vegetables for the children's diets. A midwifery program helped train over 60 Mayan women from villages throughout the region in prenatal care and safe delivery techniques.
PLENTY was one of the first relief organizations to enter New Orleans, getting past federal roadblocks to bring supplies to survivors just three days after Hurricane Katrina. PLENTY helped establish a base camp for volunteers and channeled funding to Common Ground, a local group assisting in clean up, legal defense services, and the operation of free clinics. PLENTY volunteers purchased and restored a home in the area to serve as a headquarters for housing relief volunteers and construction crews helping to rebuild homes.