Back in the ’70s, earth-sheltered housing enjoyed great popularity, thanks in part to the energy crisis resulting from the 1973 oil embargo. Adventurous builders and researchers explored various forms of earth-sheltered building, from underground excavated spaces to surface-level buildings with earth piled in berms against their walls. People searching for alternatives to conventional building showed that sheltering a building with earth could reduce energy costs for both heating and cooling by half or more — at little or no increased expense.
Once again, America’s over-consumption of energy has made energy efficiency an important consideration in all facets of our lives, including home design. In addition, there is a new awareness among “green” and “natural” builders that we are “paving and roofing this country to death,” in the words of architect and underground-building guru Malcolm “Mac” Wells. (See “The Father of Earth-sheltered Design,” Page 119.)
An earth-bermed house can reap about 95 percent of the energy advantages of a fully underground home, and adding an earth roof, or living roof, further promotes planetary health by “greening” the house’s footprint. Most buildings have a negative impact on the planet. Combining earth-sheltered walls with a living roof has the potential for the least negative impact.