These self-sustaining, eco-friendly, off-the-grid homes will blow your mind.

The term “Earthship” may conjure images of spaceships and UFOs. But this house concept is totally grounded.

In fact, Earthships are self-sustaining, zero-waste homes made from natural and recycled materials, and built with systems for water harvesting, sewage treatment, food production, solar and wind electricity, and thermal/solar heating and cooling.

We’re talking true off-the-grid living.

From sea to land

The Earthship concept originated with self-sustaining ships, called sea-dwelling ships; these vessels have everything necessary to sustain life for months at a time and produce little waste.

When applied to homes built on land, the name evolved to earth-dwelling ships.

Inspired by this concept, Earthship Biotecture, founded by architect Michael Reynolds, has created hundreds of sustainable, off-the-grid homes all around the world from recycled materials. Although controversial at first, the concept is gaining steam.

A six-point plan for zero waste

Over the decades, Earthship Biotecture has perfected six design principles to guide the creation of their zero-waste homes. They dictate that Earthships must:

Be made from recycled materials Create their own passive heating and cooling Create their own passive electricity Harvest and treat rainwater Produce food Contain and treat all sewage

Following the principles creates “possibly the best house on the planet,” according to Earthship Biotecture Team Leader Phil Basehart.

Every Earthship — from the 480-square-foot “simple survival” model to a 6,000-square-foot high-end custom home — adheres to the six tenets.

It’s all about the environment

Climate makes no difference for an Earthship — they can be constructed almost anywhere. The firm has plans to build homes in regions from tropical to deep-winter.

The construction materials vary as much as the locations. Tires jammed full of earth make walls that will last for thousands of years.

Panels from old washing machines and refrigerators headed for the dump become metal roof panels. Recycled bottles create stained glass; bottle caps turn into mosaic flooring; and scrap wood from commercial pallets become doors.

Indoor greenhouses and systems that treat and reuse gray water to grow food are present in all Earthships. Water is used three times: once for bathing or washing dishes, then it goes into the indoor greenhouse, which purifies the water, and, finally, it can be used to flush toilets. Some models also have fish ponds as part of the system. Nothing goes to waste.

As whimsical as you want

Given their unique construction materials, Earthships tend to be a bit whimsical in their appearance. The plaster used for walls creates more rounded edges and shapes than typical stick-frame buildings. The spaces are also filled with natural light because of the use of passive heating and cooling.

Another positive feature: Disturbances from neighbors will be a thing of the past. The homes are so solidly built that outside noises are barely detectable.

A typical two-bedroom Earthship measures 2,000 square feet, and includes all the typical comforts of home. Wi-Fi? Yes. Cable television? Sure. High-end kitchen? Done. And it’s all powered by solar energy or wind-generated electricity.

Earthships can be “over-the-top ornately designed and finished … or they can be other-worldly,” says Earthship Biotecture Education Director Kirsten Jacobsen.

The Earthship lifestyle

Creating an Earthship is more than simply constructing a house. It’s a lifestyle.

Earthship Biotecture’s clients run the gamut. They include “young couples who don’t want to pay a mortgage; people who are interested in learning how to build their own homes; people who live on a fixed income and don’t want monthly bills; families of all ages, artists, professionals and business owners,” states Jacobsen.

Building the average Earthship takes about six months, and prices vary depending on the size and location. The structures require little to no maintenance once completed, and the best part is, there will be no utility bills piling up.

“The owners are now happy when it’s sunny for power, happy when it’s raining because they’re collecting water — they’re more in tune with their environment,” Jacobsen notes. “It is completely fulfilling and inspiring.”

Learn more about green home-building trends.

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