Earthship Kansas

Anatomy of an Earthship

Editor’s note: The Millsteins’ earthship is a modified version of the “classic” design invented by maverick architect and builder Michael Reynolds in the 1970s in Taos, New Mexico.

Earthships are made from used automobile tires that have outgassed their toxic additives. However, there’s much more to an earthship than recycling automobile tires. Designed to provide an environmentally responsible, independent lifestyle, they provide maximum comfort while treading lightly on the earth.

The automobile tires are usually placed on compact subsoil (sometimes on foundations), then packed with dirt using sledgehammers or pneumatic tamping devices. After the first course of tires is packed, another course is set in place on top of the existing row. The tires overlap, creating a running bond pattern—like bricks in a wall—to ensure structural stability. These tires are then packed with dirt. There’s typically no need to drive rebar through the tires to support them, and the tires don’t have to be attached to one another.

When completed, the tire walls are covered with stucco or earthen plaster that hides any evidence of them—and blocks any potential outgassing. The stucco or plaster also fireproofs the thick, solid walls, which resemble those of adobe and straw bale homes.

In their classic form, earthships typically consist of a series of articulated U-shaped rooms that open onto a corridor housing the kitchen, bathrooms, and planters, along with components of many of the key systems that foster independent living: the solar hot water system, a water purification system, and the batteries that store electricity produced by the house’s photovoltaic panels, mounted on the south wall.

The front face of most earthships typically consists of a sloping or vertical glass wall. When oriented to the south, the glass allows the low-angled winter sun to enter the building and heat the interior. The dirt-filled tire walls absorb excess energy, and at night the stored heat radiates back into the structure, keeping its occupants warm and cozy throughout winter months. In addition, earthships are typically bermed with dirt on all sides except the south to buffer them from extreme weather.

The south-facing glass also provides sunlight for indoor planters, which produce fruits and vegetables and help purify graywater—wastewater from washing machines, bathroom sinks, and showers. Graywater runs through a pumice bed in the planter’s base, where microorganisms purify it. Plants growing in the overlying soil soak up the water and plant nutrients, further cleansing the wastewater. The naturally purified water can then be used to flush toilets.

Drinking water is collected by the earthship’s unique V-shaped roof, which funnels rain and snowmelt into large cisterns. When needed, the water is purified by a series of filters, then heated by a solar collector.

For more information, check out Earthship Biotecture’s website at Earthship.org.

—Dan Chiras