Earthships are buildings made of recyclable materials and are able to provide itself with electricity. They are aesthetic to look at and attract an alternative, sustainable and independent lifestyle. In times of climate change increasing rents and housing crisis, Earthships become increasingly popular. To point the way against wasting resources and climate change by using recycled materials and living in self-sufficiency. How works an earthship and are they a true alternative to conventional structure? // By Sebastian Nußbaum
07.02.2018//In front of an grassy hill a wooden Infobox is sticking out. "Earthship" is written in bold typed letters. Following a path around the hill it becomes clear the hill is more than soil and grass. It looks like the ground has foaled a giant bubble – a bubble with windows and doors, like a hobbit house with a sun-room. The Earthship is grounded on the site of Doepark Nooterhof in Zwolle, a town in the Netherlands and is used as a public teahouse. It is early in the morning, customers has not yet arrived and the smell of Falafel is in the air. The visual appearance of the Earthship is similar to its unconventional structure. Specially round and curved proprieties are predominant in its architecture. Characteristically, the Earthship's interior architecture are glass bottles that serve as a substitute for clinker bricks in the walls. Zwolle's Earthship contains 7000 glass bottles within its walls. When sunlight shines upon those coloured glasses, a play of colours dances across the wall, like a church window. Much of the glass forms mosaics that crest the walls artfully. The builders has inspired by architects like Antoni Gaudi and Friedensreich Hundertwasser.
The matter with the tyres
Scrap tires are the heart of an Earthship. They are a wall and a heater in one. The rear walls is, like a clinker-containing wall, structured of layered and offset tyres. Layer by layer, the tyres are filled with compressed soil. Another important component of this heating concept are the wide front windows. The structure of an Earthship aligned such that its windows face south, collecting the maximum daylight and infuse the tyres with thermal energy. If the outside temperature is sinking, the collected thermal emits into the room. This principle of thermal energy transfer is called convection. Noticeable for Zwolle's Earthhouse is the indoor climate, bearing in mind that the teahouse in not actively heated. Outdoors a cold wind is breezing around bare trees, the heaven is drab and covered. By contrast, the indoors is a balanced warmth, a temperature that harmonizes the radiating thermal and cold autumn weather. Altogether 1000 tyres were used in the building's construction. In the finished Earthship the tyres lay unseen, with clay plastered over them. The wide windows give a panorama view.
Power and water supply
How self sufficient is an Earthship with regards to its power supply and technology? For example, are the solar cells on the roof enough, or is an additional mounted wind turbine needed? How much wattage is needed? The Earthship in Zwolle is an teahouse for them a professional kitchen with an appropriate amount of wattage is required. In this particular case it is necessary to be able to draw on a electricity grid. This Earthship has two water tanks with a capacity of each 2000 liters. Therein filtered rainwater will be collected and used to flush the toilettes. But its not for drinking, because through the european drinking water ordinance, rainwater is not potable water approved.
Gift to the community
The Earthship was started in 2008 as a gift to the Zwolle community by a buiding society. For the occasion of the society's centenary, the building society SWZ wanted to set it as an example for sustainable building. Not for promoting it as a new problem solving, but to light a point in the right direction. Looking for a suitable ground, the society's cooperation with Doepark Nooterhof started. After a ten month constructing phase, in June 2009 it was done and marks the first Earthship in the Benelux countries.
Crucial point construction permit
Lots of Earthship-projects looking like that in Zwolle – as an idea for a joint project and supported per a solidarity of interests. The problem is that glass bottles and tyres are not licensed construction materials, an absolutely necessity for legal construction. Certainly there are exceptions, which can be alleged with explanatory statement. For example, if there exists a scientific aspiration or a special public interests. ”If such exceptions wouldn't be allowed, innovation wouldn't rise and "that's closely the reason why Earthships have character of experiment, and as a concept for classic town houses unsuitable", says architect Ralf Müller
Earthship projects will implemented by international aid workers with special know-how and enthusiasm for Earthship projects. Officially educated and qualified experts, as well as specialist companies who are specialised in Earthships, are non-existent. And for compressing the 1000 tyres by hand and with a sledgehammer, one must rely upon the help of friends. As an architect, Ralf Müller has accompanied the construction of Germany's first Earthship in Tempelhof. For him especially the social compatibility as characteristic of sustainability gets complied. "I have never experienced a construction site where so many enthusiastic people were working," says the Earthship expert. In comparison to similar concepts – for example like passive houses – it is this special enthusiasm that makes the difference. To build a sustainable house by using recycled materials in all manners of its construction, that would be the point, where Earthships go one step further in the direction of sustainability, says Ralf Müller.