By, Ben Williamson
Earthbag construction is a natural building technique that uses local materials to build low cost structures. Using materials available usually from earthworks near, or on, the building site, this style of construction lends itself to aesthetically pleasing curvilinear designs that are strong and insulative.
The basic technique uses poly-fabric sacks filled with earth and then tamped on top of each other with barbed wire in between for strength. The bottom tier is filled with gravel and sits atop a gravel base at subsoil level. Chicken wire is then attached to the final walls surfaces with sod staples and plaster is then applied for a smooth finish. Earthen plaster mixes can create beautiful earth tone finishes that are comforting and warm. Domes and arches help one area flow to the next.
With an artistic eye, you can really create a unique structural feature both inside your home and out. Glass, windows, doors, shelves, vents, and many other objects can be framed into the wall. Fireplaces and rocket stoves can become part of a heat-holding wall mass, or a bench nook that stays warm all winter long. The possibilities are open, the design is fun, and the workload is best tackled with a group of family and friends.
On our yurt build in Louisa County, VA we used earthbags for the foundation wall which seals and insulates beneath the wooden deck platform supporting the yurt. The yurt was built on a slope, so the earthbags helped tie the home to the land and curved well with the round shape and sloping land. We used a stucco plaster finish that could be painted, but we were pleased with the look after two coats.