Earthbag Pit House
In the fall of 2000 at TerraSante Village, our first experiment with earthbags was a simple, partially subterranian adobe-in-a-bag (aka earthbag) 12-foot circular structure with interior ferrocement retaining wall below grade.
The structure has a slightly sloping flat roof, one door, one window, an opening skylight, as well as 4-inch PVC "vent" tubes in the walls, and a floor of sand from the local wash and cement.
Material for the bag walls was excavated from the interior space, walls were stuccoed with 1" chicken wire mesh for extra strength. The roof is built-up 4x8 beams on 2-foot centers, with a 1/2-inch plywood deck, roofing felt, mesh and stucco. The ceiling is insulated with 8 inches of reused fiberglass. Doors, windows, and ceilings are made of recycled wood, metal, and glass.
Most of the structure was created by two people in about 6 weekends (thank you Cory and Andreas), with additional volunteers completing the stucco and finish work over about two years. Total cost of materials was about $600.
The space has a special energetic quality which is magical, probably due to its circular nature, and a surround of earth. It is quiet and tends to be cool inside when it's too warm outside, and vice versa.