Evidence that sustainable homes are both affordable and achievable will be on display this Sunday 13 September, as residents across the country open their doors as part of Sustainable House Day.
The close to 150 homes taking part will offer public tours and information sharing on topics ranging from renewable energy, designing for passive solar benefits, aquaponics and making use of reclaimed materials.
Jointly hosted by the Alternative Technology Association and EnviroShop, the national open house event aims to showcase the value of sustainability in building and renovating. As well as talks and tours by the homeowners, sustainable architects and designers will also be sharing their expertise.
ATA chief executive Donna Luckman said the event aimed to educate and inspire people as to what they can achieve in their own homes and gardens.
“It really is amazing what we are seeing people do – from aquaponics and backyard food farms to thermal mass walls, off-grid energy and beautiful renovations,” Ms Luckman said.
“Motivations are clearly about improving environmental footprint but they are also about creating much more liveable and economic spaces.”
Here’s a taste of what you can see.
Austerity Era Home – Pascoe Vale South, Victoria
Creating a more liveable space was the priority for Paul McKay, who had been living in his “terribly dumpy austerity era weatherboard” home for 20 years before his partner motivated him to start renovating two years ago.
McKay has invested around $40,000 in the improvements to his Pascoe Vale South home, which he said is now virtually zero-net energy, growing a vast proportion of the family’s food, and warm and cosy in winter.
The process of going greener has also created new income streams in the form of timber milling and making pellets for pellet stoves and heaters from grass clippings and wood waste.
In the initial stages, when the internal plasterboard was removed, he found there was no insulation, just studs and the exterior weatherboards.
McKay says he had done a straw-bale building course, but it couldn’t easily be retrofitted. So instead straw was stuffed in between the studs with a layer of Sisalation behind it for water proofing, chicken wire to keep the straw in on the internal face, and the whole then covered with a mud render.
A pellet oven with a wet back provides heating for the house via a hydronic system comprising a hot water manifold feeding into seven radiators.
He has invested in a hammer mill for converting wood chips into sawdust, and a pellet maker that uses sawdust or grass clippings procured from a lawn mowing company to make the pellets. This, he said, will eventually become an income stream.
Another income stream is the timber milling equipment he purchased, which has produced all the timber used for construction and is also producing saleable timber from urban recycled timbers.
The sharing economy has played a major role, with McKay using tradespeople found through HelpX, which is similar to Willing Workers On Organic Farms (WWOOF).
In exchange for four hours electrical, plumbing or other construction work each day, travellers are fed and housed by the family.
The garden with its aquaponics system, bees and chickens has been producing fruit, vegetables, eggs, honey and around 1.5 kilograms of fresh fish a day.
The house has a three kilowatt solar PV system that is grid connected, and McKay said nothing is spent on electricity.
It’s a showcase of sustainability, but McKay said that was not his prime motivation.
“I’m basically just a really lazy man. I want to be able to earn a really luscious living without having to work,” he said.
“It’s getting pretty close – in a year or two I will probably never have to work again.”
Passive Resistance House – Semaphore Park, South Australia
This $240,000 home constructed by builder Beechwood combines lightweight timber construction with reverse brick veneer to improve thermal performance, and has Aircell insulation wrapping the building plus slab-edge insulation. The majority of windows are double-glazed with high-performance framing.
The floors are polished concrete throughout all living and wet areas, with an inslab hydronic heating system throughout, and the carpet in the bedrooms has a low insulation underlay to enable heat transfer. An internal courtyard captures northern sunlight for the back section of the house.
The house has a 4kW solar PV system and evacuated tube solar hot water system, and 10,800 litres of rainwater storage that is plumbed to every tap in the house. Energy efficiency initiatives include almost 100 per cent LED lighting, energy-efficient appliances and energy monitoring.
Casa 31 – City of Vincent, Western Australia
An architect-designed renovation and extension of a 1936 Queen Anne Federation home, the house features what the owners believe to be Perth’s largest Coolgardie safe for low-tech cooling. This system comprises drip-fed irrigation that wets the fabric on the upper level’s facade, so when the hot wind blows through there is a cooling effect.
During the build process, removal of material from the site was minimised, with materials including bricks, timber, windows, doors, paving, insulation, kitchen and bath cabinets, light fittings, tiles and landscaping reused or upcycled.
Timber-framed fixed and operable screens protect the interiors from hot summer sun, and a north-facing highlight window achieves passive winter heat gain. The house also has a solar PV grid-connected system and flat-panel solar hot water system, and uses low-energy light fittings throughout.
The Vicker Ridge – Logan Village, Queensland
A four bedroom, three bedroom luxury home, this owner-built house achieved better than net zero for water and energy in 2014 – exporting more energy to the grid than it used, and harvesting more rainwater than the quantity used, treated via chemical-free means and then reused on site.
The net positive result was achieved even though the household uses the clothes dryer, has a home theatre, multiple fridges, swimming pool and even outdoor airconditioning[?!].
Energy efficiency features include efficient lighting and appliances, energy monitoring and use of retailer controlled off-peak tariff, as well as a solar PV system and solar hot water.
The house is a lightweight construction with some recycled materials, roof and wall insulation, and extensive use of clerestory and louvre windows for cross-ventilation. There is over 100,000 litres of rainwater storage, and both greywater and blackwater treatment systems installed.
Eco-Tourism Village – Huon Bush Retreats, Tasmania
Entirely off-grid for both energy and water, Huon Bush Retreats comprises 11 buildings from tepees to two-bedroom houses set within the Mt Misery Habitat Reserve.
The dwellings are lightweight construction comprising steel, timber and mudbrick, with full insulation, wood stoves with wetbacks for heating and hot water, in addition to solar PV systems. In the reception building, the 12-volt solar is converted to 240-volt to run office equipment.
The resort has 130,000L of multi-tank rainwater storage and a water treatment system that separates out grease, lint and particles before the water enters evapotranspiration beds. The use of composting toilets means there is no blackwater discharge.
It has a private community reserve and grows its own timber and firewood, and calculations using the National Greenhouse Office methodologies have shown it has an overall positive carbon balance.
Chifley PassivHaus, ACT
One of only a handful of homes in Australia that have been certified under the European PassivHaus standard, this nine star NatHERS home was built using structural insulated panels for thermal performance.
The home has double glazing throughout, a hot water heat pump and a heat exchange ventilation system. Passive solar principles were used in the design, with north-facing windows, deep eaves for shade in summer, high thermal mass floors and windows placed for cross-ventilation.
Airtight membranes completely seal the house and insulation was used to decouple the slab from the ground. The owners say that independent testing measured an air infiltration rate of 0.1 ACH at 50Pa, about 200 times tighter than the average Canberra home, and that the house needs virtually no cooling or heating.
Millers Point Residence – Sydney, NSW
Architect Caroline Pidcock is opening the doors of her super-sustainable Millers Point renovation, a labour of love that showcases how modern technology like solar PV can co-exist with restoring a historic slate roof and a complete low-toxic interior makeover.
The house is a State Heritage-listed house, which limited the changes that could be made to the building envelope and interiors.
“However, the devil is in the detail and this project enabled some interesting thinking on how we can make a 130-year-old house very comfortable by subtle means,” Pidcock says.
Aspects of the makeover include:
- moving towards a totally electric-powered house with maximum PVs on the roof and carefully selected energy-efficient appliances, fixtures and lights throughout, including ceiling fans and hydronic heating
- sealing up the house, adding secondary glazing to existing windows and doors and installing appropriate new glazing where required
- installing high-performance insulation in the roof space and the few new timber framed walls
- carefully selected paint and timber finishes, with a range of options selected so we could see how they worked
- a restorative food producing garden
See Sustainable House Day for information on homes open in your area.