Earthship principles

oostzijdeHere follows a brief description of how an earthships functions.

The features at a glance are:

  • extremely low power consumption
  • own water supply and sanitation
  • independent of the sewage system
  • lower building costs
  • outstanding energy performance
  • harmonious fit with landscape

All these characteristics apply for the approximately 100 earthships that have been built worldwide over the last 35 years to the complete satisfaction of their residents and the local governments. In other words, the pioneering phase of the building concept has past and while perhaps new by Dutch standards, an earthship is no longer an experiment. All technical questions relating to building and safety are answerable and supported by years of practical experience in both construction and habitation.

More information about the earthship building concept along with technical data, photographs and maps can be found at www.earthship.net, the website of the aforementioned architect Michael Reynolds.

 

1. Energy use and thermal mass

Heating constitutes a substantial portion of the total energy consumed in conventional homes. Earthships are designed to minimize this expenditure by focusing on the optimal use of thermal mass whereby the interior temperature of the houses is stabilized year round at approximately 15 degrees Celsius without the need for additional heating.

This is achieved by a glass facade along the entire south-facing side of the buildings. The three remaining walls are made from earth-rammed (recycled) tires and backed up by massive earth berms. In our project we are also making use of the thermal mass below ground by floor-isolation. During the coldest period of the year, additional heating can be deployed via special high performance wood burning ceramic heaters or other heating installations.

Solar panels can easily meet all the electricity demands of the residents.

2. Water supply and sanitation

Earthships are designed so as to minimize or eliminate any environmentally harmful impact. Besides being CO2-neutral, they are also fully autonomous in terms of water supply. In our project, we will purify ground water so as to make it suitable for human consumption.

We are in the process of deciding on the best handling of waste water in order to meet Dutch Waterboard regulations.

3. Construction costs

The costs of building an earthship are lower than that for conventional houses. Ecologically responsible construction is therefore within reach of basically all income-groups in the population.

The low construction costs are due to three factors:

stamping tiresReuse of materials

Stacked earth-rammed old tires are the load-bearing walls, non-load bearing walls can be filled with empty bottles, cans or other non-biodegradable waste materials. Parts of the insulating layers can be made from freely available recycled materials (e.g. plastic cups). Other reusable materials can be obtained from local demolition and waste management companies.

Use of locally available materials

Additional building materials are as far as possible taken directly from the work site itself. This applies in particular to earth for the construction and finishing of the walls. Even when materials are not locally available, transportation distances are kept as small as possible. Think for example of the use of local wood resources.

Volunteers

Experience in the construction of earthships worldwide shows that such projects are very attractive to groups of enthusiastic volunteers. Consequently, the labor costs for the construction project are minimal. In Europe many volunteers are interested in building, for example to learn how to build their own earthship.

A large part of the construction costs is made up by costs for installations (solar panels, water cleansing filter etc), resulting in slightly -  not substantially - lower building costs than conventional housing. On the other hand, fixed costs for earthships are greatly reduced.

4. Energy performance / environmental impact

Earthships have been assessed on energy performance and environmental impact by the Dutch Institute for Building Biology and Ecology NIBE. The GreenCalc calculation programme helps determine the environmental impact of a building in comparison to conventional building. This programme has shown that an earthship is over nine times more efficient than a conventional house. This is the highest score ever awarded to a building concept.

5. Landscaping

noord-oost-blik

Because the earthships are surrounded on three sides by an earthen wall, a good landscape integration is relatively simple. When the project is realized, passers-by who view the houses from the north, east or west will see the project as hills in a green landscape.

Given the project’s orientation in regards of the sun, the northern edge of the community can also serve as a natural transition between town and countryside.