Phillip Johnson must be the Energizer Bunny of sustainable landscape designers. We were at a City of Whitehorse Sustainable Living Week presentation about sustainable home and garden design. Phillip had launched into a talk about his landscaping philosophy based on sustainability principles. As he bounced around the lectern, we knew it was going to be an entertaining, informative evening. His talk was followed by a presentation from the architect Marc Dixon. Though not as extroverted, Marc was equally passionate about sustainable design, this time for houses in an urban setting.
Ideas for creating a sustainable urban landscape
Phillip was keen for us to think about designing a ‘house and land package’. The two should run in parallel with choices in one area (eg location of windows) informing choices in the other (eg what can be seen in the garden outside those windows). The landscaped garden could also provide services for the house – source of stored rainwater for use in the house or a source of cooled air coming off a trickling stream of water.
Indeed, the management of rain water was a key theme in Phillip’s talk. He recommended we find ways to manage the rainwater that fell on a property. In some parts of the block, such as the driveway, it should be allowed to permeate into the soil and not run off to the nearest storm water drain. Other rainwater, particularly that falling on the roof, can be harvested in tanks and a billabong to provide a useful resource for the home. Storing water in a billabong has the added bonus of providing the basis for a thriving ecosystem right there in an urban setting. When built from natural materials (eg rocks that could be found on the building site) and planted with indigenous plants, there is the possibility of attracting local wildlife to create a natural living space in the garden. Essentially, we were encouraged to find ways to use water on the block, not divert it into storm water drains for someone else to deal with. Reducing the initial flow to storm water also means the run-off system doesn’t have to cope with a sudden surge. This leads to local flooding when it becomes overwhelmed. Neighbours benefit when more rain water is kept where it fell. Of course, there is a limit so Phillip was keen to point out it was likely some water would have to go to the drains. It’s not a good idea to flood a neighbour when the billabong overflows.
For ideas as to the key features of a landscaped area, Phillip recommends bio-mimicry. What looks good in nature? What do we find attractive in a natural setting? Nature has spent millions of years experimenting with different landscaping designs. Why should we try to create something from scratch? Having a theme means the landscape design will be sustainable because the components already work together in nature.
Protecting the existing mature trees on a block is an important part of any design. David is a firm believer in this philosophy as well. Apart from providing the foundations for an urban ecosystem, the old trees represent the history of the block. They should be integrated into a new garden design as respected elders in the plant world.
Use passive design elements in sustainable homes
Marc suggested a sustainable home should incorporate a few key passive design elements – correct orientation on the block, cross-ventilation for cooling, good insulation and clever use of light & shade.
Knowing where the sun will be during the seasons is the starting point for the design of many parts of the house. Which windows should allow light through in winter but not summer? What parts of the house are going to have the highest heat load in summer? What shading is required to reduce that heat load. As Marc pointed out, prevention is better than a cure. Externally shaded, double glazed windows significantly reduce the amount of solar energy that enters a home to increase the internal temperature.
Be clever in how shade is provided. Marc showed one design where the solar panel array formed part of a shading system for a north facing room. Long, thin windows were used to allow sunlight into a room during winter, but hardly any in summer when the sun was higher in the sky.
Get the council involved early
Both presenters recommended getting the council involved early in the design stage of an integrated house and landscape package. At the very least, they can provide guidance on what they will and won’t accept. In a more positive light, the suggestion was to go proactive and work towards getting the council on board. Find out what sustainable building/landscaping concepts the council was promoting. Include them in the design and then highlight those items in the discussion. Ideally, the council representatives would then become vocal supporters of the design package as they could see their ideas being put into practice.
Possible theme for our sustainable home and garden design
Mulling over the ideas from the talk has generated a possible theme for our development, in particular the first home which will probably have a larger garden area.
Let’s wind the clock back a bit. Could we create something closer to the earlier settlements? Could we create a story? The landscaping would evoke an indigenous setting of trees, shrubs and grasses surrounding a small billabong. The house was sited near the billabong as a source of fresh water. There are connections to the local environment through the house using passive design features (eg shading from the surrounding vegetation) and taking advantage of local resources (eg water supply, solar energy). Nearby, a patch of the native vegetation has been cleared to provide space for a veggie patch and orchard. This reflects a balance between providing a source of locally grown produce for the occupants of the house while maintaining a habitat for the local wildlife.
Something to think about anyway.