Earthship is out of this world

Take a pile of old tyres, tonnes of dirt and throw in some cans and bottles and various other recycled bits and pieces and the result is a bed and breakfast like no other.

But then Martin Freney sees little place for conventional design and materials when constructing the ultimate self-sustaining home.

The University of Adelaide PhD student is building an 'Earthship' on his four-acre property at Ironbank in the Adelaide Hills in a project which is exciting environmental enthusiasts and testing government approval agencies.

Earthships are the creation of US architect Michael Reynolds and are starting to appear around the world. They don't require heating or cooling, even in harsh climates, and they operate independently of electricity, water and sewerage grids.

Mr Freney's Earthship is the second in Australia - another has been built in Queensland - and his PhD aims to establish the thermal efficiency and environmental impacts of the homes compared to traditional dwellings.

His research has taken him overseas to log temperatures in Earthships built in the US and the results are encouraging.

"I've now got data which confirms anecdotal evidence about the efficiency of these homes and I've developed a simulation model which can predict the thermal performance of an Earthship in different climates,"
Mr Freney said.

"With the help of my PhD supervisors, Terry Williamson and Veronica Soebarto, I've also written a paper on the theoretical performance of Earthships in different parts of Europe where they are starting to be built."

Earthships challenge conventional design by having a sun-facing 'greenhouse' at the front which acts as a natural convention 'engine' to heat and cool the home without energy.

"The concern was that in Australia the homes would overheat, but with some design modifications my study demonstrates there is still a cooling effect in summer," he said.

An industrial designer by profession, Mr Freney leapt at an opportunity to build an Earthship after organising a trip to Adelaide by Mike Reynolds in 2009. The two have since visited each other several times and developed a good working relationship as he perfects his modelling program.

Mr Freney has run workshops for architecture and design students - and many other interested people - who work alongside him to help construct the Earthship and gain a greater insight into self-sufficient living.

The design includes an internal garden to grow food and filter captured water, it has minimal solar power and the external tyre structure can be rendered with a choice of materials.

But gaining approvals can be problematic.

"Planning approval was given for the home to become a bed and breakfast and structural engineering has been completed, however construction was stalled because of delays in receiving building approval which was eventually given in June," Mr Freney said.

"I was a bit concerned that the absence of concrete footings under the tyre walls might be an issue, but the engineer I used was very enlightened and confirmed the design was structurally sound.

"It has also passed energy assessment, but only just because the nationally accredited software is not capable of accurately modelling the heat transfer through the greenhouse, the living space and out through the very thick tyre and earth walls."

The CFS also gave the thumbs up describing the home as highly bushfire resistant.

However, one issue involves the use of grey water for the indoor garden which has been queried by health authorities. Mr Freney intends using captured rainwater four times - for a bath or shower, irrigating the indoor garden, flushing the toilet and then for irrigating the outdoor garden.

"I'm in the process of convincing the heath authorities that this is perfectly safe and this will involve a PhD student conducting scientific testing of the greywater system," he said.

With development approval now in place Mr Freney plans to run a series of workshops in January 2014 to complete the project. For information on the workshops email Mr Freney at martin.freney@internode.on.net