Green buildings, which incorporate the principles of sustainable development are becoming increasingly popular in Australia and now represent 34% of the total share of construction activity in the country, according to Dodge Data and Analytic’s World Green Building Trends 2016 SmartMarket Report.
This proves that once-dismissed, sustainable and environmentally-friendly ideas are now gaining traction.
One of these ideas is Earthship construction, which uses recycled, reclaimed and natural materials to build off-grid, passive solar homes that do not rely on traditional carbon-heavy building designs and materials.
Created by architect Michael Reynolds 40 years ago, the Earthship construction principles incorporate specialised systems for thermal/solar heating and cooling, renewable energy, in-house sewage treatment, integrated water harvesting and food production.
After being brought to public attention following the 2007 release of the film Garbage Warriors, there are now more than 2,000 Earthships around the world and Michael’s company Earthship Biotecture has developed construction drawings for a global model Earthship. This model can be adapted anywhere in the world and modified for almost any climate.
Agari Farm, a group of natural builders and permaculturists, has helped to facilitate the build of the first three-bedroom council-approved Earthship residence in Kinglake, Victoria on behalf of Daryl Taylor.
Daryl was one of thousands of people whose home was destroyed in the Black Saturday fire storm in 2009 and saw the re-building process as an opportunity to innovate. He spent five years gaining council building and planning approvals to build a global model Earthship, which began construction in October 2016.
Known as Kinship, the residence has been featured on ABC Radio National, ABC Online, 3CR, RRR FM, in the Age, The Australian Weekend Magazine, The Herald Sun and the Leader Newspaper, as well as being the first stop on CERES’ Australian Sustainability Tour.
The Build team was able to visit the site as part of an article for our trade publication, where we spoke to Agari Farm interior designer and draftswoman Dani Wolff-Chambers.
Dani says Kinship is being built using around 60-70% natural or recycled materials, including tyres, sand, glass bottles, straw, clay, second-hand glazing, salvaged 100-year old pieces of Australian hardwood. Tin roofing and concrete slab flooring were required to obtain council approval but Agari Farm is keeping their use in the construction process to a minimum.
Thermal mass earth berm located at the south end of the building serves as the foundation of the home and is held in place by a retaining wall made from tyres filled with site soil. This thermal mass and a North-facing glass wall form the basis of the passive heating and cooling systems. In winter the northern sunlight warms the thermal mass, which stores the heat and radiates it back as temperatures drop. Then in summer, cooling tubes, which are run underground through the thermal mass, release heat from the air to the surrounding soil, cooling the air as it enters the house.
“With these passive systems the Earthship stays a constant temperature and we’re going to be installing temperature and humidity sensors in the building to monitor this,” says Dani.
Typically, Earthships also incorporate food production, in-house sewage treatment and the ability to use water four times but some Australian council regulations restrict these practices.
Kinship does include an indoor planter for food production but because it’s located on an urban block it cannot contain in-house waste and sewage treatment. This means black water is treated in a sewage treatment plant rather than a contained septic tank.
However, Dani says this could change as more councils begin to recognise alternative systems.
“Councils have begun to take permaculture into account in building approvals and a lot of new constructions in Australia are using alternative energy systems such as solar and passive ventilation. People are starting to get on board and alternative systems are becoming more common.”
Agari Farm ran workshops at Kinship during the building process, educating both home owners and builders about alternative construction.
“When people think of an Earthship they think of a tyre house that looks like a space ship but really it’s just a set of construction principles that can be incorporated into any conventional building design,” says Dani.