Introduction
Solar panel above front door
Three energy and water efficient homes are on display in Canberra from February 2006 to May 2007 in the "Eco-living Exhibition". The web site includes a 264kb Flash interactive tour of the homes, with floor plans and garden designs. The general public can visit the real homes during the opening hours and school groups can book a tour. As well as be showcases for the particular products and designers, the display homes are GreenSmart certified, and intended to educate the public about an integrated approach to sustainable design for energy and water conservation. Designers of the houses, gardens and water systems will be on hand to answer questions at set times. The houses are at North Watson, in Canberra's inner north, near the main road to Sydney.
Tour
Sample of insulated concrete wall
In April I looked at one of the houses, at 13 Roma Mitchell Crescent, and talked to Ngaio Fitzpatrick, from Strine Design. This is a single story, four bedroom detached house of 207 square m. It uses insulated precast concrete panels. These were completed with a clear finish is some parts of the house, but can be painted.
Photovoltaic cells above the front door
The house has photovoltaic cells above the front door to produce electricity. The panel looks an attractive feature of the hose from the street. But as you walk in you can see the electrical connections above your head. Like the concrete walls, this might be something you want covered in other than a display home. The electricity generated by the house is fed back into the power grid, earning the householder a credit against their power bill. Compact fluorescent lights are used to reduce power consumption.
Moveable awnings and solar chimney
Solar chimneys are fitted on the roof to remove hot air in summer. These also provide an attractive roof feature. The solar chimneys are air vents on the ridge caps of the roof which can be manually opened or closed as required. There are also moveable awnings outside the north facing bedrooms to shade them in summer, which can be moved up to provide winter sun, or lowered to completely cover the window.
Terracotta panels
Several of the rooms have terracotta panels on their eastern walls, near the windows. These are designed to act as thermal mass. In winter during the day, the sun comes through the windows and warms the panels. This heat then is radiated out into the room. The system used seems to be one designed for external cladding of commercial buildings, with a metal frame screwed to the wall and terracotta panels clipped to them. The terracotta has a very attractive finish, giving both an old fashioned warm feeling to the room, while being a modern rectilinear design. This system would be good for retrofitting to older homes with hollow wooden walls, but doesn't seem to be needed in this one with solid concrete ones.
The concrete slab is insulated at the edges to reduce heat loss. In-slab electric heating is fitted in the bathrooms, which don't get direct sun and so are cooler. While this would be very cosy on the toes, I am not sure this is such an energy efficient idea, compared to other forms of heating, but at least the householder could use off-peak electricity for the slab. The slab has a polished finished and left visible as the flooring. Like the walls, this is not a finish everyone will like (it looks to me like a concrete warehouse), but other fishes are possible.
The kitchen has a "Cent-a-meter" electricity meter. It displays the cost per hour on a large screen above the kitchen bench. This should be useful to remind the householder how much power is being used. In the future it should be possible to build this into an household houshold system. The energy use could then be displayed on a mobile phone, or a wall mounted, flat screen.
The house collects rainwater from the roof for garden irrigation. It also has a Perpetual Water grey water treatment system installed. This cleans greywater from showers and basins to a standard which could be used for washing clothes and flushing the toilet. However, it is not clear if the system is being used for this. I would be happy to use the water to flush the toilet, but would take some convincing it was okay to wash clothes and in that case a simpler system could be used.
Trellis and solar panel
The front wall of the house, which faces the west, as a steel mesh trellis for growing a creeper. This is designed to shade the wall from the harsh Canberra sun in summer. This should also considerably soften the slightly harsh look of the concrete walls. There is evacuated-tube solar hot water system, with electric-booster. This is a set of glass tubes on the roof, which looks like a modern sculpture.
Overall the home passes the credibility test. Unlike many envro-display homes it is something I could imagine being able to afford to buy and be happy to live in (with a coat of paint over some of the concrete). Look as hi-tech as the design by Ian Douglas for my Smart Apartment, which is perhaps a good thing. It could do with a few more homely environmental touches, such as a worm farm. Presumably it has a ultra low water dual flush toilet cistern.
Environmentally Sustainable Cluster Housing
What Canberra needs is environmentally sustainable cluster housing equivalents to the display homes in North Watson. The general public, builders and developers in Australia, could then learn about sustainable design principles for apartments. An example of this is my proposal for Environmentally Sustainable Cluster Housing, for Canberra's centenary in 2013.