Living in a sustainable house is not as hard as you might think.
Sophia MacRae and her son Derek have made The Iris House in Camperdown their home after completing the build for around $200,000 and achieving 7.7 stars in the National House Energy Rating scheme.
Ms MacRae is encouraging anyone thinking about sustainable housing to educate themselves, take the plunge into the market and reap the benefits.
"I really want other people, who don't have a lot of money, to know they can live in a house with low running costs," she said.
"I think it's just so nice to not stress out about bills. I have basically no gas bill and I designed the house to use hardly any electricity.
"It doesn't cost much to get a house built the right way."
Ms MacRae returned to Adelaide from living in Barcelona about 12 years ago. After meeting a range of people who were interested in sustainable housing and through her own studies in town planning, she began to research how different housing options could work for her.
The family moved to the south-west in 2017 and earlier this year Ms MacRae completed the build of The Iris House.
"I'd been following sustainable living when I moved back to Australia but I always felt like it was an impossible dream," she said.
"I'd look at these houses and think how can I ever make this possible?
"Finally I've proven that even if you don't have a lot of money you can do it."
The Iris House faces north meaning it gets great sunlight to warm up the building. Ms Macrae has also collected a stack of wine bottles, filled them with water and placed them along two walls so when the sun hits them, the thermal mass of the water radiates heat throughout the house, well into the next morning.
The house is not connected to the gas network, which means Ms MacRae can save money and know the building isn't emitting fossil fuels.
The 86 metre-square electric-running house also has a reverse-cycle air conditioner, double-glazed thermally broken windows and eaves among other sustainable features.
Ms MacRae and Derek moved into The Iris House two months ago and are encouraging others to join Sustainable House Day's online events on Saturday.
"People can learn so much and explore houses all over Australia," she said.
"There's so many resources out there to help you make your own home energy efficient.
"I feel like I've hit the jackpot hit and I love the south-west, we're here to stay."
Sustainable House Day's online events can be viewed through sustainablehouseday.com with live panels, Q&As and tours taking place on Saturday.
You can view The Iris House via sustainablehouseday.com/listing/affordable-sustainable-house
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