Earthships represent a convergence of modern alternative construction methods and ancient building materials. The typical earthship is constructed of a combination of natural and recycled materials, incorporating everything from bottles to tires to mixtures of earth and clay. Primary goals of earthship construction also include energy independence--hence the name "earthship," a building designed to be as autonomous as a ship at sea.
Earthship construction takes advantage of the rammed earth technique, which forms exterior walls by building up layers of construction materials within a wooden framework and then compressing them. Traditional rammed earth homes use a mixture of soil, water, gravel, and lime. Earthship walls, on the other hand, are often constructed of automobile tires that have been packed with soil. These tires are laid similarly to traditional bricks and mortared together. Mud is then used to fill the space left between each linked tire, and the whole wall is covered with a layer of stucco or plaster.
The thick-walled earthship home provides excellent insulation in a wide range of climates. These insulating properties are further enhanced by passive solar design, which can be used to maximize or minimize a home's exposure to sunlight depending on whether heating or cooling is desired. Solar panels as well as wind and water turbines are often built into the home to provide renewable off-grid power.
Earthships in their modern, energy-independent incarnations have their roots in Taos, New Mexico, at the Earthship Biotecture firm owned by Mike Reynolds. Reynolds has been responsible for the development of several earthship communities in the local area, as well as putting together kits and workshops for potential homeowners. The earthship movement has since spread abroad, with workshops being offered in France, England, and South Africa. Students interested in alternative construction may also apply for an internship at Earthship Biotecture to learn the craft.