Houzz Tours
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Sustainable Homes
Houzz Tour: A Super-Sustainable Home Houses Three Generations
This house, designed specifically for a multi-generational family, takes sustainability, accessibility and affordability to a new level
There are three pillars of sustainability we should aim to balance when building or renovating. Many of us only concentrate on economic sustainability (keep that budget in check or you might end up with a hefty mortgage and only half a house). The eco-friendly warriors among us might prioritise environmental sustainability instead (tread lightly or suffer the wrath of Mother Nature), but while economic and environmental sustainability are crucial, there is also social sustainability to consider. This means the project should be inclusive, and not displace the wider community.
The house seen here, named Solar Sollew by building design firm Positive Footprints, is a pre-designed, industry-leading home which considers all three pillars of sustainability, to create an energy-efficient, mid-range project home that is also wheelchair accessible. Trifecta!
The house seen here, named Solar Sollew by building design firm Positive Footprints, is a pre-designed, industry-leading home which considers all three pillars of sustainability, to create an energy-efficient, mid-range project home that is also wheelchair accessible. Trifecta!
From the outside, Solar Sollew looks like any regular modern home. And in many ways, that’s the beauty of the project. It demonstrates that an environmentally sustainable home doesn’t need to look any different from other homes in the street. The fact that it doesn’t stand out in the street is also an example of social sustainability – the home doesn’t dramatically alter the character of the neighbourhood.
By using readily available materials and standard building techniques, costs can be managed, ticking the economic sustainability box. At first you might not notice the gradual slope or the width of that path to the front door, but that’s a hint that the home is also wheelchair accessible – an important consideration for the brief, since this is a multi-generation home and the owners’ elderly parents live here too.
By using readily available materials and standard building techniques, costs can be managed, ticking the economic sustainability box. At first you might not notice the gradual slope or the width of that path to the front door, but that’s a hint that the home is also wheelchair accessible – an important consideration for the brief, since this is a multi-generation home and the owners’ elderly parents live here too.
Inside, the home is surprisingly light and bright. While the house recedes deep into the block (typical of suburban homes), clerestory windows in the living area help to bring light deep into the house. This is particularly noticeable in rooms which are further to the south.
The ground floor consists of a shared open-plan living, dining and kitchen space, which opens onto a sunny north-facing backyard. This space serves as a hub for all three generations of the family to gather for meals, relaxation and entertainment. The grandparents’ bedroom, with ensuite bathroom, is also located on the ground floor to make it easily accessible for them.
The ground floor consists of a shared open-plan living, dining and kitchen space, which opens onto a sunny north-facing backyard. This space serves as a hub for all three generations of the family to gather for meals, relaxation and entertainment. The grandparents’ bedroom, with ensuite bathroom, is also located on the ground floor to make it easily accessible for them.
In fact, everything on the ground floor is designed with accessibility in mind, making it easier for the grandparents to navigate. Flowing spaces in the kitchen, dining room and pantry, wider-than-standard doors, a cantilevered kitchen bench and low power points all allow for easier wheelchair manoeuvrability.
Above all, the owners wanted “a home that was energy- and water-efficient to minimise bills, and was in line with how they felt they should be living on the planet. That is, one that is as low impact as possible,” says designer Chi Lu from Positive Footprints.
The owners also wanted lots of light and warmth in their home, so measures were taken to ensure this was provided in the most eco-friendly way possible. The home is designed to be passively warmer in winter and cooler in summer. A reverse recycled brick veneer wall in the living area, along with polished concrete floors, help to moderate the home’s temperature.
The challenge was to bring the winter sunlight deep into the rooms further to the south, according to Lu. “The solution was to create a tiered design with a raised central clerestory, to bring northern light deep into the belly of the house,” she says. “This means that it heats quickly when the sun comes out in winter.”
In summer, the concrete and brick help to keep the home cooler, and the higher angle of the sun in summer means it is blocked by carefully designed eaves. At night, opening clerestory windows and ceiling fans draw in cooler night air and capture sea breezes.
The owners also wanted lots of light and warmth in their home, so measures were taken to ensure this was provided in the most eco-friendly way possible. The home is designed to be passively warmer in winter and cooler in summer. A reverse recycled brick veneer wall in the living area, along with polished concrete floors, help to moderate the home’s temperature.
The challenge was to bring the winter sunlight deep into the rooms further to the south, according to Lu. “The solution was to create a tiered design with a raised central clerestory, to bring northern light deep into the belly of the house,” she says. “This means that it heats quickly when the sun comes out in winter.”
In summer, the concrete and brick help to keep the home cooler, and the higher angle of the sun in summer means it is blocked by carefully designed eaves. At night, opening clerestory windows and ceiling fans draw in cooler night air and capture sea breezes.
Reverse brick veneer construction (seen here) is the opposite to what we’re used to in Australia. The typical brick veneer house has the bricks on the outside and lightweight plasterboard on the inside. This method of construction is great for durability, but it wastes bricks’ inherent thermal mass properties.
By flipping the bricks to the inside, and using corrugated iron, fibre cement or weatherboards outside with a layer of insulation between, your home with have far superior thermal performance, meaning less energy waste, a more comfortable home and cheaper utility bills at the end of the month.
By flipping the bricks to the inside, and using corrugated iron, fibre cement or weatherboards outside with a layer of insulation between, your home with have far superior thermal performance, meaning less energy waste, a more comfortable home and cheaper utility bills at the end of the month.
Large double-glazed bi-fold doors, which are thermally broken (containing an element that lowers thermal conductivity) connect the indoors with the backyard, without jeopardising the home’s thermal performance. Given that windows and doors are responsible for the largest proportion of unwanted heat loss/gain, it makes sense to pay extra attention to the performance of glazing. This design proves that you can have generous openings – really connecting indoors and outdoors – while still being energy efficient.
While concrete is often not the most environmentally friendly product to make, being very carbon intensive, it does have a number of benefits. Concrete is a great example of thermal mass, helping to store thermal energy, and it’s very hard wearing, so it requires very little maintenance and has a very long lifespan.
Lu and the team took steps to mitigate the problems with concrete, while drawing on its inherent strengths, to create an insulated floor slab for the home. This ‘eco-slab’ uses up to 60% cement replacement (utilising waste products from other industries instead) as well as recycled materials, to reduce its ecological impact. It also has recycled glass seeded into the surface of the wet concrete, so when the surface is polished it has a unique glimmer – a nice combination of style and substance.
Lu and the team took steps to mitigate the problems with concrete, while drawing on its inherent strengths, to create an insulated floor slab for the home. This ‘eco-slab’ uses up to 60% cement replacement (utilising waste products from other industries instead) as well as recycled materials, to reduce its ecological impact. It also has recycled glass seeded into the surface of the wet concrete, so when the surface is polished it has a unique glimmer – a nice combination of style and substance.
The stairs and the flooring upstairs are made from bamboo, a sustainable alternative to timber as it is a fast growing grass where the shoots are harvested without killing the plant. A bright yellow wall in the stairwell helps to liven up what might otherwise be a dark space, continuing the sense of a bright, light-filled home.
Upstairs are the parents’ bedroom, the children’s bedroom, a bathroom, a rumpus area (pictured) and a generous deck. “While the ground floor and garden make sure that there is plenty of shared time between the generations, the upstairs provides a retreat for the young family when required,” says Lu.
To help counteract the fact that hot air rises, and aid in keeping the second floor cooler in summer, special phase change sheets were installed behind the plasterboard walls. These help to absorb excess heat and maintain a pleasant temperature in the upstairs bedrooms and living areas.
To help counteract the fact that hot air rises, and aid in keeping the second floor cooler in summer, special phase change sheets were installed behind the plasterboard walls. These help to absorb excess heat and maintain a pleasant temperature in the upstairs bedrooms and living areas.
It’s impossible to tell from this image, but that lush looking lawn is hiding a secret weapon in the home’s environmental sustainability arsenal. Three metres below the surface is a looped pipe, which is actually an ‘earth tube’ cooling system. This uses energy-efficient fans to draw warm air out of the home, bringing it underground where the soil sits at about 18 degrees celsius. The lower temperature of the ground chills the air, before the system returns it back to the house.
A grey water recycling system, which helps to keep the lawn looking green, also helps to increase the conduction of heat from the earth tube.
The earth tube cooling system was also one of the biggest challenges of the project. “As there is no such thing as an off-the-shelf earth tube cooling system, it needed to be designed from the ground up, using logic, common sense, internet trawling, and a fair bit of ‘try it and see’,” explains Lu. “Fortunately it has been successful.”
A grey water recycling system, which helps to keep the lawn looking green, also helps to increase the conduction of heat from the earth tube.
The earth tube cooling system was also one of the biggest challenges of the project. “As there is no such thing as an off-the-shelf earth tube cooling system, it needed to be designed from the ground up, using logic, common sense, internet trawling, and a fair bit of ‘try it and see’,” explains Lu. “Fortunately it has been successful.”
A framework was erected along this east-facing wall, which acts as support for creeping plants. In addition to looking beautiful, the creepers will eventually grow to shade this wall from the brunt of the morning sun.
Raised planter beds in the garden, used to grow organic produce for the family, are at a good height for wheelchair-accessible (and/or back-friendly) gardening.
From the sunny backyard you can see some of the utilities which help to make the home more eco-friendly. A good-sized rainwater tank provides water to the toilets and laundry. Solar panels on the roof collect energy to help power the home. You also get a good sense of how the eaves help to keep the sun out during summer, and how nice the connection between indoors and outdoors is when those bi-folds are opened.
While most of the energy efficiencies come from the carefully planned 9-star passive design, an integrated Building Control Management System (designed by MacTech) operates all of the home’s active systems to ensure peak performance. It has the ability to open and close windows, turn on fans and operate the earth tube cooling system, to ensure the home maintains a comfortable temperature.
This design tackles all three pillars of sustainability to create a comfortable home for all three generations of a family. Perhaps this a model more of us could consider as our population ages and energy efficiency becomes ever-more important.
This design tackles all three pillars of sustainability to create a comfortable home for all three generations of a family. Perhaps this a model more of us could consider as our population ages and energy efficiency becomes ever-more important.
Who lives here: A multi-generational family – two elderly grandparents, two parents and two young children
Location: Seaholme, Victoria
Size: 230 square metres, 3 bedroom, 2 bathrooms
Designer: Positive Footprints
That’s interesting: The home achieves a 9-star energy rating, and the ground floor and garden are wheelchair accessible to cater for elderly grandparents.