The Return of the Root Cellar
Written onJune 26 , 2013
The globalized food chain that Americans have increasingly relied on for over 50 years has begun to show its weaknesses—and inevitable failure. There are many weak links in the chain, but the weakest are storage and distribution. These aspects of modern food production contribute significantly to energy consumption: fossil fuel is required to ship food from far away, to keep food fresh during long–distance transport, and to store food over a long period of time. How can we opt out of this destructive system?
Enter the humble root cellar. This simple structure, and others like it, offer homeowners a chance to save money on food purchases, trips to the grocery store, and energy bills. They also allow local farmers to have readily available storage for winter CSA shares. In short, root cellars offer us a way to addressfood security in simple, accessible, and sustainable ways—and they can be built in most homes.
Found almost everywhere in the world in some fashion, food storage structures have a history dating back to 3,000 BC. Some of these ancient structures, which are still standing, can be found in the Middle East, where they offered access to cool earthen temperatures, shaded food from the desiccating effects of the sun, and offered protection from freezing and hot temperatures.
Root cellars and other forms of subterranean food and crop storage structures were also once the norm on farms and in homes in northeast North America. During the 17th and 18th centuries, root cellars were built at almost every farmstead as a means of keeping food safe throughout the winter when exposure to freezing temperatures could easily turn a hard labor’s bounty into famine for a family.
In Vermont, food storage structures were created in basements (cellars), submerged into hillsides, and established in outlying farm buildings, such as barns. Many structures contained several rooms or chambers, which allowed for the storing of different types of crops at their optimum conditions. Some structures even contained springs and wells, that allowed for the creation of cold–water baths for cooling milk, beer, and other beverages.
With the advent of pasteurization and canning in the 1700s, convenience in food storage was born, and food was able to be stored for much longer than pickled or raw foods. As industrialized areas grew, “stores” took the place of cellars and city folk began to rely on readily available food bought daily or weekly. With the development of refrigeration, root cellaring and its associated ways of life took their final blow and were considered an aspect of antiquity. Only on actual farms and in rural areas would you still find people storing crops throughout the winter.
Recently, farmers and other supporters of sustainable agriculture have remembered the necessity and accessibility of low–energy forms of food storage. CSA members are taking responsibility for storing what they pick up weekly from their farmers, and localvores who like to buy their foods in bulk are finding spaces big enough to fit their bounty. Communities and villages are building shared food storage spaces with all sorts of materials. Root cellars are becoming a form of social capital, offering resplendent bragging rights and the safe and secure feeling of knowing where food has come from.
Storing food isn’t rocket science, but it’s an art that must be engaged in with patience, reverence, and determination to live, eat, and work healthfully. It also helps to know some basics. Root cellars and similar structures meet storage needs by three means: conduction, convection, and thermal mass.
Conduction: The Earth is one big superconductor of energy and it retains a constant mean temperature four feet below ground. Underground masonry walls conduct these temperatures into the structure, providing protection from heat in the summer and cold in the winter.
Convection: This process uses two vents, one to bring cold air into the structure, another to release warm, stagnant air back outside. Convection also releases vapor so that condensation does not form on vegetables and bring rot, mold, and bacteria.
Thermal Mass: Materials that are dense and have lots of weight have large amounts of thermal mass, and thus maintain temperatures for longer periods of time than low–mass materials. Thermal mass is generally used in passive solar applications for retaining and releasing heat. In cooling, thick masonry walls and the earth itself are used to store cold energy.
Design requirements for root cellars and other storage structures include:
Shade from the hot sun: for example, on the north side of a house or hill
Venting: this should always be above snow line, and located (ideally) on gable ends to keep out rainwater
Drainage: while humidity is key for roots, too much can be bad; make sure to include footing drains and other forms of daylight drains to keep humidity controllable; standing water and condensation promote rot
Insulation: used to keep the cold in when the structure is less than four feet from the ground surface
As for the food, it all has different needs, but none should be kept above 65 degrees Fahrenheit. Many foods can be stored up to six months in some situations. Foods such as brassicas and leeks should be dug up roots and all and be replanted in sand and moist peat in containers. Carrots and other roots can be best maintained when repacked in moist sand. Apples and other fruits need their own chambers and vents to release ethylene gas.
Creating your own food storage space can be done in several ways. Retrofitting existing basements is a great option for homeowners looking to use already available space. Creating an attached but separate root cellar allows for access through the existing house and limits having to brave the cold during frequent winter trips. Then of course, there is the iconic, standalone root cellar, which could have a shed on top or be completely subterranean, allowing for less insulation and more thermal mass, and hence more protection.
All of these structures are ideally created with some form of masonry building material. Poured concrete, surfaced bonded block, stone, gunite, concrete board, and/or brick are the most common materials used for thermal mass, load bearing strength, and water protection. When building a storage structure, don’t forget to obtain all local and state permits, as underground structures require special permitting in some places.
There are several alternatives to full–size root cellars that would allow for storage in a city, the suburbs, or where there is a need to feed only one or two people. These include clamps—insulated and above–ground caches covered in chicken wire, hay bales, and hardware cloth for rodent protection—and pantries, which are usually uninsulated spaces with vents for cooling and which are maintained in the spring, summer, and fall months by opening a door at night to let in cool air and closing the door in the morning to keep warm air out.
Almost any interior space near an outside wall, especially a closet or an attic, can serve as storage for some, if not most of your crops. Most important is to make your storage area easy to check on, so be careful of putting it too far from your home.
Root cellars offer us a new glimpse of sustainability through the guise of food security. By creating these storage spaces, we can protect our own harvests, support our local farmers, save trips to the store, and begin to take responsibility for the economic and ecological consequences of our food consumption.
The five main conditions found in the root cellar