Earth-sheltered construction

DEFINITION: Construction of homes or other buildings mostly underground

Compared with traditional aboveground structures, earth-sheltered buildings have several environment-related advantages, in particular the fact that they require significantly lower amounts of energy for heating and cooling.

Human beings have been using earth-sheltered construction techniques since they first began creating shelters for themselves as protection against the elements. In the past, earth-sheltered buildings were often carved into hillsides or constructed from turf, but modern versions are usually made of concrete. Earth-sheltered homes have been found in all cultures and all parts of the world, from Iceland to China to the American Southwest.

During the 1970s “back to the land” movement, building earth-sheltered homes became popular with many people who wanted to live in harmony with nature. Malcolm Wells, often referred to as the “father of earth-sheltered construction,” was an architect who believed that underground architecture was a promising and overlooked way to build without destroying the land, a “silent, green alternative to the asphalt society.” Wells credited his interest in such building to an underground housing exhibit he saw at the 1964 New York World’s Fair and to a trip he took to Taliesin West, the Arizona home of architect Frank Lloyd Wright, where an underground theater stayed cool despite soaring outdoor temperatures.

An earth-sheltered building is best located on a well-drained hillside; correct excavation and preparation of the building site are critical. It is not recommended that earth-sheltered buildings be constructed in areas of permafrost, areas with high water tables, or areas with high underground concentrations.

Two basic types of earth-sheltered buildings are common: underground and bermed. In underground construction, the structure is created and then covered with earth (at a depth of anywhere from 15 centimeters to 2.7 meters, or 6 inches to 9 feet). In a bermed building, the structure is banked with earth surrounding one or more outside walls. Both types generally have earth-covered roofs. The choice between underground or bermed construction depends on the vegetation, climate, soil, and drainage of the building site area.

An earth-sheltered home may cost 10 to 20 percent more to construct than a typical above-ground dwelling, but often low maintenance costs and energy savings offset these higher costs somewhat. The earth surrounding an earth-sheltered building serves as insulation, so that the interior maintains a constant temperature. Proponents of earth-sheltered construction have estimated that families living in earth-sheltered homes can save up to 80 percent in heating and air-conditioning costs in comparison with these costs for a traditional above-ground house. The insulation of the earth on earth-sheltered homes also keeps water lines from freezing, makes these buildings safer than traditional houses during storms, and provides soundproofing. Proponents of earth-sheltered construction also note that the outer parts of these structures are nearly maintenance-free (they require no painting, for instance) and that, compared with above-ground buildings, earth-sheltered structures have fewer problems with break-ins (as earth-sheltered buildings have fewer entrance points) and with damage from fire (as they are usually built of concrete).

Problems can arise in earth-sheltered buildings if they are not properly constructed. Potential problems include poor air circulation, flooding, condensation, and water seepage. Earth-sheltered homes may also not have very good resale value, as the numbers of people seeking out such homes remain somewhat limited.

Bibliography

Everett, Jaeger. "Earth-Sheltered Home: An Eco-Friendly, Passive Housing Alternative." Insteading, 5 Sept. 2023, www.homecrux.com/earth-sheltered-homes/94481/. Accessed 16 July 2024.

Roy, Rob. Earth-Sheltered Houses: How to Build an Affordable Underground Home. Gabriola Island, B.C.: New Society, 2006.

Sood, Gaurav. "15 Best Earth-Sheltered Homes That Promote Sustainable Living." Home Crux, 26 June 2024, www.homecrux.com/earth-sheltered-homes/94481/. Accessed 16 July 2024.

Underground Space Center, University of Minnesota. Earth Sheltered Housing Design: Guidelines, Examples, and References. New York: Van Nostrand Reinhold, 1979.

Wells, Malcolm. The Earth-Sheltered House: An Architect’s Sketchbook. Rev. ed. White River Junction, Vt.: Chelsea Green, 2009.