What is an Earthship?

by David Knapp

typical American home is radically different than an Earthship. Most homes are designed to protect it's occupants from the environment. The Earthship works in the opposite direction by taking advantage of the cycles of Mother Nature. A normal subdivision would be in great trouble if the incoming electrical power lines failed for an extended period of time due to a natural disaster such as a tornado or earthquake. Such homes would loose their ability to function without electricity to provide lighting or AC power for appliances such as a furnaces, deep well pumps, or freezers. Earthships produce their own electricity, water, and food supply. Due to the Earth berming concept, they are far less likely to sustain damage from natural disasters.

"Planters" are found in all rooms along the south side of the Earthship including kitchens and bathrooms. A typical house plant can mushroom into the size of a small tree with little known features of that species popping out. You can practice "raised bed" gardening indoors all winter long. Only natural fertlizers from earthworms and composting are needed to produce a rich crop of produce. Finally, you can participate in indoor gardening without being terrorzied by mosquitos.

An Earthship is a dwelling made mainly from recycled components and is independently powered from any utilities. Few, if any, non-renewable materials are used to build this vessel. Constructed mainly from recycled automobile tires and aluminum soda cans and mortar, this structure is built into the ground to take advantage of the ability of the Earth's thermal tempering. A typical Earthship generates it's own electricity from a solar photovoltaic array (solar panels) and collects fresh water by catching naturally soft rain water. All used gray water from kitchen, bathroom sinks and showers is recycled by filtering it through long planters along the front windows which produce much of the households food supply. The gray water nourishes the roots of the plants and is cleansed in return. The recycled water is run through a mechanical filter and recovered to provide a supply for the low flow flush toilets. This way, all recovered water is used at least two - three times.

An Earthship receives all of it's winter heating from large sloping double pane windows located on the south side. The lower angle of the Sun in Winter provides radiant heat which is absorbed by the thermally conductive walls and floor. At night time, this heat is released back into the rooms. The high angle of the Sun in Summer blocks the heat by the design of the Earthships roof, preventing the penetration of the Sun's long wave radiation. The Earth berm and the internal walls (constructed of automobile tires and earthen plaster), has a very strong capacity for moderating inside temperatures due to it's large thermal mass. A rear skylight brings in extra light and allows for fesh air ventilation under the front windows by exiting warmer stale air above the north side of the rooms. Prewarmed air is often brought in via "earth tubes" which travel approximately six feet under the ground. Travelling a hundred feet or so, the air is prewarmed or precooled to approximately 58 degrees F before entering the Earthship.

By the Winter Solstice on December 21st, the Sun shines deep into the rooms. The floor feels toasty warm to the bare feet with the sun shining on it. The best floor surface is darker ceramic tile, earthen mortar or flagstone. On June 21st during the Summer Solstice, the sun only hits the front planters. Without direct sun contact, the Summer time floor will feel refreshingly cooler. Insulated sunshades were later added to sheild the Summer Sun and to prevent heat loss on Winter evenings.

The skills required to build an Earthship can be learned in relatively little time. The automobile tires, each packed with about 300 pounds of soil, lock in place like a jig-saw puzzle. Internal non-load bearing walls are constructed of aluminum cans and mortar. All surfaces are coated with earthen adobe plaster and are very pleasant to view. You can decorate the inside of an Earthship to look any way you want. Once built, it is impossible to tell the interior contents of the walls. Often, people avoid examining non-traditional housing because the exterior doesn't quite look like a "Colonial" or "Victorian" style house. It is very hard to set aside our human dogma, but those that do learn to live and work in harmony with Mother Nature. This is one case where your pocket books wins also!

Many Earthship owners build out-of-pocket and therefore construct a smaller dwelling and add on as they can afford it. A room has a basic U-shape and you can add additional "U"s as money permits. With a mortgage free home, the pressures to work at a "high income" stress filled job are lessoned. This allows you to pursue meaningful work in your lifes passion after you construct your Earthship.

I have just scratched the surface on Earthships. The information presented on this page should be considered as a brief introduction. The reader is encouraged to explore the other Earthship web sites, as many are published by those who already live in an Earthship. Earthship Global Operations has published a series of newsletters, books, chronicles, and video tapes designed for the do-it-yourself home builder and those wanting to learn more information about Earthships.