The homes that we live in are the epitome of industrial pillage of the earth. Massive amounts of cheaply built lumber teeming with damaging chemicals from the structure of our homes. To heat and cool our homes, fossil fuels are pumped into our homes leading to excessive greenhouse gas emissions.
Despite the comforts and luxuries that modern-day housing offers, for the most part, it is one of the most unsustainable aspects of our lives. Earthships have been in development since the 1970s and offer a unique and more ecologically friendly way housing alternative.
The Ecological Cost of Modern Housing
The most common construction style which has come to dominate the American housing market is a timber frame made from pressure treated pine wood 2x4s and plywood sheeting. The house façade is covered by either plastic siding or imitation brick and the inside walls are usually made from dry wall.
Since most new houses built for the market in the industrial world are huge structures often measuring well over 2,000 square feet, lots of wood is needed thus contributing to deforestation. The housing industry in the US accounts for close to half of all the softwood timber cut down each year. Over an acre of old growth forest is clear cut every 66 seconds and almost half of that wood is used in homes that whose expected lifetime is less than half a century.
Most houses also use generous amounts of concrete for foundations. Concrete is another unsustainable building material as it accounts for at least 5% of all greenhouse gas emissions. Furthermore, some concrete has traces of radioactive elements within it.
Almost all modern-day homes are heated and cooled by central heaters and air conditioners that run on fossil fuels. It is estimated that almost half of all the energy used in a home is to heat and cool the house. If each square foot of a modern house needs 50 kwH to heat and cool, then for a 2,000 square foot house, this adds up to around 100,000 kwH per year. This causes a large amount of greenhouse gasses to be released into the atmosphere and also leads to a dangerous dependence on fossil fuels. Almost no industrially built home takes into consideration energy efficient building methods that rely on sustainable energy sources. What´s more, many local building codes actually prohibit certain natural ways to heat and cool a home.
Another issue with modern housing is the sheer amount of toxic materials used in the construction of these houses. Asbestos is a known carcinogenic that is still used in many forms of ceiling tiles and insulation. Chromated Copper Arsenate is used in almost all pressure treated wood that is a hallmark of the lumber used for framing modern houses. Though the EPA phased out the use of this type of chemical, many older houses will still have this type of pressure treated lumber. Dozens of other chemicals are also included in the lumber used in modern construction and the effects of these chemicals are unknown.
We have come to accept that the building industry should necessarily be monopolized by a group of specialized contractors and that any type of home that doesn’t offer modern day comforts (no matter how unsustainable they may be) is equivalent to living in a cave.
What Are Earthships?
Earthships challenge the commonly held assumption that: 1) it is impossible to build your home, and 2) homes cannot be a completely sustainable part of the landscape. At the same time, Earthships prove that sustainability doesn’t have to be equivalent with dull, drab and simple housing styles. Rather, many Earthships are beautiful, large homes with many of the comforts that people have come to accept from a home.
Earthships claim to be 100% sustainable homes that incorporate a number of different features. One of the central tenets of Earthship construction is passive solar design. By angling the home towards the south (in the northern hemisphere) and building large windows on the south facing side of the home, Earthships are able to generate much of the heat they need for the cold winter months through capturing the light and the heat from the sun.
Additionally, the walls for Earthships are made from sources that can be considered a thermal mass, or some material that will store heat over time. Originally, most Earthships were made from recycled tires that were rammed full of earth and stacked on top of each other like bricks. By the time each tire is filled with soil, it weighs close to 300 pounds making the walls of an Earthship an extremely sturdy thermal mass. Earthship walls can also be built from adobe, cob, or earth-bags as well.
The inner walls are usually made some sort of recycled material such as recycled aluminum cans bound together by concrete. The cans are then plastered with a natural, earthen plaster so that on the inside it is impossible to tell that you are surrounded by nothing more than walls of tires. Earthships are also designed to harvest all the water that they need from the local environment, mostly through rainwater catchment systems connected to the roof. Rainwater is sifted through t a silt catching device before being redirected to a cistern which provides water for your household needs.
All of the water used in Earthship homes is either reutilized or recycled. The greywater from showers and sinks is redirected to toilets where it is used for flushing the toilets. The greywater is then passed through a botanical cell where the water is purified with the help of beneficial bacteria and a peat moss filter. This water is then used once again to flush toilets a second time.
Another of the defining aspects of Earthships is that they are built to be 100% energy independent and off-grid. They generate all of their own energy needs through the installation of solar and wind green energy systems. This energy is stored in deep cycle batteries that are stored on the roof.
While most of the heat from Earthships is generated through the passive solar design method and through the storage ability of the massive thermal walls, additional heat can be supplied through wood stoves. New Earthship designs have begun to be built in a “double greenhouse” fashion, with two panels of south facing glass making up the entire southern wall of the home. This traps even more heat and keeps the house warm over the winter.
A natural cooling system that relies on convection is also used in Earthships. Pipes are buried underground to gather the cool air from the earth before being brought in to the home. A small window is left open at the top of the home to allow for a steady air flow of cool entering from the bottom and warmer air escaping from the top of the home.
The Example of New Mexico
Reynolds began building his initial Earthship design in New Mexico. Because of the warmer climate and the abundance of sun, the Earthship passive solar design and the thermal mass walls adapted perfectly to local conditions. Since the 1970s when Reynolds built his first “proto” Earthship model, dozens of Earthships have been built by individuals in the region. The Earthship Biotecture is the world headquarters of the Earthship movement. Located in Taos, New Mexico, it is a sort of living museum and school for Earthship construction and sustainable living. They also offer an Earthship Academy where people can go to receive hands on training to prepare for their own Earthship construction.
Additionally, the Greater World Earthship Community is a neighborhood made up entirely of Earthship homes. The 633 acres contains absolutely no power lines or sewage drainage pipes. A 100% off grid community, the Greater World Earthship Community shows how people can come together to live in a sustainable way.
Earthships for a More Sustainable Future
Earthships incorporate numerous elements of sustainable design to offer people the comforts of an industrially built home with the reliance on unsustainably sourced materials and dependence on fossil fuel energy. Through recycling, or “upcycling” materials from our consumer civilization, and through ecological design, Earthships offer one of the most sustainable human dwelling alternatives.