Sanctuary: Modern green homes

Open Plan Gone Mad?

This is an excerpt from an article in Sanctuary magazine issue 16.

Open-plan living has many benefits, but also potential drawbacks in loss of control over noise, heating and cooling, says building designer Dick Clarke.

Words Dick Clarke

If there’s one idea that has permeated contemporary home design more than any other, it would be “open plan”. Open-plan living has many tangible benefits, but also some serious drawbacks if not done well. Combined living, kitchen and dining areas should be no larger than 70 or 80 square metres – any bigger and things get out of control. It’s reasonably well known that houses with large living areas and circulation spaces which connect the house from one end to the other have poor thermal control, but if they have lots of exposed thermal mass inside, such as concrete floors and masonry walls, they may also have extremely poor acoustics.

The concept of open-plan living comes from our love of big living areas with plenty of light, where all household activities happen in close proximity. This is in stark contrast to houses built before the 1950s, where kitchen, lounge and dining activities each had their own separate room, quite disconnected from the rest, and certainly disconnected from the outside world. During the 1950s and 1960s, lounge and dining often came together in one larger space, with direct access to the kitchen. Then during the 1970s the kitchen was liberated from its second-class status, freed from isolation and brought joyfully into the core of the household.

If you’d like to read the rest of this article you can buy this issue here.

Building your sustainable dream home

From Sanctuary issue 10. More articles like this

By Alan Strickland with Judy Celmins

Excerpt: Wanting to live sustainably is not a fringe occupation. Millions of Australians want to make a difference to their homes and lives. But as a member of the Alternative Technology Association and an organiser of Sustainable House Day the question I am constantly asked is: “Where do I start?”

Many people come away from Sustainable House Day fired with enthusiasm. They see homes that are warm in winter and cool in summer, without the need for large heaters or airconditioning. They see water-wise homes that gather rainfall and greywater and use these to produce wonderful, food-producing gardens. They want that for their own home. The problem is that visitors only see the finished house. Time doesn’t usually allow visitors to ask the owners about how they went through the whole saga of planning and creating a sustainable home. The wondering, the indecision, the frustration and dead ends, and the many stages of learning they had to go through.

This article aims to help fill that gap. The more you learn before you start, the easier the process will be and the less the likelihood of repeating the mistakes that others have made before you.

Further information

This article is the combination of two online posts at shmeco.com: “I’d like a sustainable home but where do I start?” by Alan Strickland and “Building the self-sufficient dream” by Judy Celmins. Alan Strickland is the Alternative Technology Association’s South Australia Branch Treasurer. Judy Celmins is a director and co-founder of shmeco.com. shmeco.com invites people to exchange their ideas, stories and experience on sustainable living choices. shmeco are managers of Sustainable House Day.

www.ata.org.au
www.shmeco.com
www.sustainablehouseday.com
www.yourhome.gov.au
www.sanctuarymagazine.org.au

Free home health checks

This is an excerpt from an article in Sanctuary magazine issue 8.

The Australian Government’s Green Loans program, launched on July 1 2009, aims to help homeowners improve their existing home. As part of the program, more than 1000 people will undertake Home Sustainability Assessor training to become accredited Green Loans assessors.

A tailored home sustainability assessment, coupled with access to a four-year interest-free loan of up to $10,000, will enable homeowners to make immediate energy and water-saving changes, from draft-sealing to installing solar panels and greywater systems.

Getting a free home sustainability assessment is the first step to qualifying for a Green Loan of up to $10,000. To find out if you are eligible for a Green Loan or to register for a home sustainability assessment, go to www.environment.gov.au/greenloans.

Apart from reducing your carbon footprint, making your home more environmentally friendly is a timely investment. The next 10 years will see the housing market shift towards environmentally friendly homes in response to pricing shifts for water and energy, smarter environmental building regulations and consumer demand.

Design for climate

This is an excerpt from an article in Sanctuary magazine issue 6.

One size does not fit all. Australia has eight climate zones, ranging from tropical to alpine. Make sure you employ a designer who is familiar with your zone and who designs climate-appropriate buildings (for instance light-weight and ventilated in hot, dry climates, well insulated and with good solar access in cool climates).

In tropical and hot, dry climates, orientate the house to exclude the sun year-round and to maximise cross-ventilation. In all other climates, your aim should be to minimise the summer sun and maximise the winter sun, which basically means a northern orientation.

Couple your “passive solar” design with thermal mass (materials that absorb heat energy) to retain the warmth of winter sunlight and/or the cool of summer shade.

Hot sun, cool house

This is an excerpt from an article in Sanctuary magazine issue 6.

The sun is beating down on the roof. The garden is wilting and so are you. Wouldn’t it be nice to turn some of that heat against itself?

You may be surprised to know, it’s actually possible to convert heat on the outside of your house into a cooling breeze inside. Solar airconditioners are coming your way.

The models in development now mostly use evacuated solar thermal tubes, like the ones used in many solar hot water systems. Instead of drawing on mains power on the hottest days, pushing power grid peak loads into the red, these systems would just hum along on solar energy. And the hotter it is, the better they work.

Consensus is that solar aircon for homes could be only a couple of years away. Currently there are several types of system in development.

How will they work?

One of the most promising systems uses evaporation. The system uses a desiccant to remove humidity from the air, which is then re-humidified using wet pads so the air delivered to the building is both cool and not too humid. The desiccant is then solar-heated to remove the moisture it has collected, so it’s ready to work again.

These systems are very far down the track in terms of technical development and will probably be among the first to be commercialised for domestic use. They’re efficient, robust and easy to maintain. A slight downside with desiccant-evaporative systems, however, is that they use a fair amount of water: CSIRO has estimated 30-50 litres on a hot day for a residential system (that’s about as much as a four-minute shower with a low-flow showerhead).

Another exciting technology, though not as far along as evaporative systems, uses ejector jet pumps, which rely on heat energy to circulate a fluid through a cycle of condensation and evaporation. The principle has been known for around 100 years, and Dr Mike Dennis, who heads the Australian National University’s solar ejector jet program, believes it has the potential to be more reliable, cheaper and smaller than comparable systems. The ANU is working with commercial partners to develop a prototype.

A winning design

Dr Paul Kohlenbach of Solem Consulting is a former research scientist with CSIRO and an expert in residential-scale solar aircon. Dr Kohlenbach says that to succeed in the residential market, manufacturers “need to develop a plug-and-play solution, pre-packaged and ready to use”.

Dr Kohlenbach believes the future for solar aircon is bright. “The CSIRO is currently researching a small solar cooling system which could be market-ready in two to three years. Overseas manufacturers have realised that the Australian market has huge potential and have started to establish themselves here.”

Probably the single most exciting thing about solar technology, he says, is that it has the potential to not only offer airconditioning, but heating and hot water as well. “A possible solar cooling kit can therefore provide all the thermal needs of a residential house.”

The ANU’s Mike Dennis agrees that a system that both cools and heats is the holy grail of solar climate-control technology. “Consider that most of Australia’s population live in a temperate climate that hardly requires airconditioning – in fact requiring a lot more heating than cooling,” he says.

If we allow climate change to continue, of course, more Australians will be concerned about summer cooling than winter heating. Even so, whichever system prevails, the winning design will almost certainly offer year-round comfort and a hot shower.

Mountain views

This is an excerpt from an article in Sanctuary magazine issue 5.

Nestled in the tiny village of Mt. Beauty in the foothills of the Victorian Alpine National Park are the aptly named Dreamers tourist apartments. These self-catering apartments boast the rare accomplishment of meeting all the criteria for a 4-star, AAA accommodation rating while simultaneously attaining a best-practice, 7-star energy rating. Still in its first year of operation, with two apartments open and two more on the way, this luxury accommodation has put environmental sustainability at the forefront of its design.

“Environmental sustainability as we practise it here is site specific. So, for example, we don’t have greywater recycling,” says Malcolm Lee, Dreamers’ building designer and owner, and former lecturer in energy-efficient building design at Melbourne’s Swinburne University. “We’re on a river flat and the water table is only two feet under the ground, so it’s fairly sensitive. Also, with the groundwater so near to the topsoil, watering is not as necessary [as in places where water is less plentiful].”

Passive systems of energy conservation feature strongly at Dreamers. Mal made a conscious decision to build apartments rather than free-standing dwellings, because shared walls enable each unit to “borrow” from next door’s warmth and reduce the need for extra heating. The party walls are made of locally-sourced rammed earth, which produces a heavy mass for excellent soundproofing.

The external walls are made from timber studs that are thicker than standard walls, which allows for a greater amount of insulation. Additionally, all ceilings and exterior walls are insulated using polywool batts of greater-than-average thickness. Thermal mass, which helps to hold heat, is provided by the rammed earth walls and concrete bench tops and floors. All windows are double-glazed to reduce heat loss during winter. This combination of a highly insulated external envelope and significant amount of internal thermal mass creates a stable and pleasant internal temperature that requires little in the way of additional heating.

“This is a challenging climate to design for,” admits Lee. “During summer it gets hot in the day but cool at night. In winter it’s cold both night and day. In effect, you have to design for two extremes of climate. But that’s the point of sustainable design, to use your local microclimate to keep you in your comfort zone.”

At Dreamers’ apartments, the second storey, which consists of the master bedroom and ensuite, is made from a lightweight timber frame and plasterboard. The effect of rising heat means that the bedroom is warmer than the rooms downstairs all year round. It was designed this way so that during the heat of the day in summer, the cool rooms downstairs could be enjoyed during the day. At night, the bedrooms would have cooled sufficiently thanks to the lightweight structure and a specially-designed natural airconditioning system.

Rather than use energy-intensive airconditioning, Lee built a natural evaporative system that draws cool air from a nearby cascading stream into the apartments. This simple, low-impact cooling technique was inspired by centuries-old Turkish technology.