The first earth berm house I ever visited was not a tiny, small or Cozy home, but the house stayed at an incredible 70 degrees during 100 degree temperatures in the high desert summer. This clinched the idea that an earth bermed or earth sheltered home is one of the best and energy-efficient ways to go if you live in a hotter climate.
Earth sheltering is an architectural practice of using earth against a building wall for external thermal mass. This reduces heat or cooling lost and maintains a steady indoor temperature nearly all year long. Earth sheltering has long been a part of human shelter. The first home-dwellers lived in caves and utilized the rock to keep the place cool in the summer, sod home dwellers of the American Plains would use the local earth to maintain heat in the winter. Eventually the prairie grasses would grow up over their walls and roof, creating even more thermal mass. These days, earth sheltering is a rare practice and is considered unconventional by most builders. Some problems like water seepage, condensation and poor indoor quality can be addressed with appropriate design, landscape planning and construction.
Several Cozy Home Plan designs can be turned into an earth berm home with several different processes. The 320 square foot Granite Mountain for example can be bermed with earth piled up against the back exterior walls and sloped away from the house. The mansard roof on the Granite Mountain will help shed water off the main berm. Another way to earth berm is to build your home into a hill. The house is set into a slope or hillside and the open part of the home can face to the south (Northern Hemisphere) or to the north (Southern Hemisphere) to obtain passive solar light and heat in the winter. The 975 square foot Gypsy Rose can be built into a hill with the appropriate foundation and wall materials.
If you want to learn more about earth berm homes, check out the earth bermed house of Dual Survival’s Cody Lundin.
Photos by Natural Building Blog and Energy.gov