Earthships As An Affordable, Sustainable Part Of Vernacular Architecture

EarthzineEarth Observation, Essay Contest 2010, Essays, Original, Sections

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University of Sussex logo

University of Sussex

By Nikolaos Meintanis

University of Sussex

Abstract

This article defines shortly the term ‰ÛÏvernacular architecture‰Û with examples, presents some of the world’s energy issues regarding homebuilding, and describes the construction process of an earthship and the systems it constitutes. There is a lot to gain from this type of building, and society needs to start thinking ‰ÛÏgreen‰Û and more economically.

Introduction

Vernacular architecture is a term used to categorize methods of construction which use locally available resources and traditions to address local needs. Vernacular architecture buildings do not need expertise of any kind: they are just simple buildings built by local people in order to have their needs satisfied. They differ from area to area. For example, dwellings built in the Philippines differ completely from those built in the Middle Eastern deserts due to different climates and different local materials. Vernacular architecture tends to evolve though and today people have to see the potential of something which looks like the perfect solution for the people’s pocket and the planet’s health. Earthships can be the perfect autonomous dwellings at low building cost, taking in mind the economical crisis of today. They are built from recycled ‰ÛÏgreen‰Û materials available everywhere. Furthermore, they have renewable energy systems which make them off the grid with low to no utility bills.

Environmental Functions Of Buildings And Affordability

Vernacular Architecture

Historically, people have always been modifying the internal environment in which they were living. Caves and other primitive types of dwellings were used in prehistoric times for protection from the external environment like rain, wind and earthquakes. These have developed later to simple artificial enclosures as civilization continued developing, and, in this way, different types and styles of identifiable dwellings started to appear around the world, depending on the climate, technologies and available local materials of the place. Therefore, the term vernacular architecture evolved, and is used to relate to these different styles of building around the world.

Energy Issues

Later, through the ages, technologies developed, cities evolved, and transport means were invented, all resulting in the more refined and complex dwellings of today as materials could be handled better and transported from everywhere. People’s never-ending desire for modification and control of the living environment resulted in a 60 percent increase of an average 2007 house’s size compared to a 1970 average one, which is a significant percentage increase1. Moreover, co2 emissions from buildings have been significantly increased as well due to this change of house size. According to the American Institute of Architects national government advocacy team, the largest source of ‰ÛÏgreenhouse gas emissions and energy consumption in America, as well as around the world, is buildings. Buildings account for an estimated 30-40 percent of all energy used globally. Citing the example of Europe, more than one-fifth of present energy consumption and up to 45 million tonnes of CO2 per year could be saved by 2010 by applying more ambitious standards to new and existing buildings2. Therefore people have to start thinking of new styles of dwellings, and new economical and energy efficient methods of controlling their internal living environment.

Affordability

When buying a house, the question ‰ÛÏwhat would I feel like if I lived in this house?‰Û isn’t usually the first one people ask– it’s more likely to be ‰ÛÏcan I afford it?‰Û They don’t ask whether the house will help them grow, to be purposeful, to contribute to the society, or whether it will make them feel small and mean. Although people have the power to change things, and the ability to make choices, these can often feel severely limited by a culture dominated by financial imperatives rather than principles of well-being. It can be hard to envision a world for ourselves that nurtures and sustains us. But why should we accept anything less? Earthships are the ‰green‰ economical future lying ahead when the people cannot keep up with the economical crisis of the present.

The Earthship structure

Earthships are ‰green‰ sustainable buildings made out of recycled everyday life materials. It is a compilation of systems which make it autonomous like waste water treatment, water gathering from rain or snow, passive solar gaining, hot water system, electricity production from renewable energies like solar and wind. A lot of problems occurring in towns could easily be solved by building earthships and adopting this economical ‰green‰Û way of building. Some of these include: sewage contamination, dwindling energy and water resources, garbage and the lack of affordable housing.

Construction Materials And Process

As already mentioned, earthships use recycled ‰green‰ materials as the primary building source. Used automobile tyres filled with earth and rammed by hammers are used for load- bearing walls of the earthship. These massive construction walls are 3 feet wide and virtually indestructible. These walls are built in rammed earth as seen from the picture on the left, resulting in thermodynamic living spaces where the temperature is stabilized and controlled better. Recycled cans and glass bottles are used for filling the gaps between the rammed tyres, and then a matrix of cement is formed which strengthens the walls. Moreover, they serve as bricks for the creation of the interior non-structural walls. It is worth noting that the cans and bottles are not used for either insulating or to strengthen the walls in any manner, but it is a way to form concrete into the walls without using more cement or wood thus making the house ‰ÛÏgreener‰Û.

Temperature, Sun And Air

The massive construction of the house acts like a storage heater, and, in conjunction with passive solar gain, the temperature of the environment is comfortable to live in every hour of the day. The large windows of the south side are more than enough to let adequate sunshine in, which is stored in the building’s fabric (walls and floor). As soon as the temperature falls some degrees, heat is released, stabilizing the temperature again to match the zone in which the dweller feels comfortable. Insulated shades can be used on the large windows in order to keep undesirable hot summer rays out, and keep heat inside during cold winter. Fresh air is circulated in the house at all times or when desirable due to dormer and hopper windows as well as skylights and doors. Everything works together for natural air convection.

Image of an earthshipElectricity Generation

Electricity is generated in an earthship by using renewable energy systems, which use sustainable sources for their purpose (sun, wind). Solar photovoltaic panels are installed on the roof of the earthship and generate electricity during sunny days in order to meet the earthship’s household and system needs, which include electric appliances, heating water, electrical water pumps. The electricity is stored in a battery bank and is more than adequate to provide the earthship with electricity even in continuous cloudy weather. A wind turbine can also be installed to boost the earthship’s energy performance if needed.

Water Management

Earthships efficiently use fresh water by reusing it four times. A cistern is installed to store water coming from rain or snow. The fresh water is prepared by the Water Organizing Module which consists of a panel of filters and a DC pump which pushes the water into a conventional pressure tank. After that, the water needed for household needs is filtered, pumped and pressurized. Water that drains from the sinks and the shower passes through a grease and particle filter and then onto a gray-water treatment planter where plants flourish from the water. The extra water not used by the plants drops into a reservoir at the far end of the planter where it pumps and sends the cleaned gray-water to fill the toilet tank for flushing. Used toilet water known as black-water is flushed outside for treatment in a conventional septic tank with a line out to a conventional leech field in an alternative series of rubber-lined planter cells, which feed the exterior landscaping while further cleansing the water.

Conclusions

The interest in Earthship building is highly noticeable and more and more people build their houses using this method. There are already a lot of earthships in Europe which attract visitors and a lot of them are amazed by the idea and concept of the earthship. Small steps towards money saving and co2 emission reducing are taken with the hope of more to come.

Thanks to Earthship Brighton!

Citations

1 http://www.nahb.org/news_details.aspx?newsID=10898

2 http://www.unep.org/Documents.Multilingual/Default.asp?DocumentID=502&ArticleID=5545&l=en