This urban ecological development in Adelaide demonstrates a sustainable urban lifestyle. The 14 environmentally sustainable dwellings built to date use a range of sustainable construction materials and systems and are independently funded with ethical finance. Water saving is a high priority, as is the use of solar energy, healthy non-toxic materials and natural ventilation systems. The local community has been supportive and involved throughout the project.
Aims and Objectives
To provide a living example of ecological, community oriented urban development in an environment where this did not previously exist.
The prevailing housing conditions in urban Australia are of suburban sprawl with little opportunity for the development of community in a car-based society. There is high consumption of both water and energy in a country where there are massive water shortages. Inner city living is seen to be unsuitable for children and families with no safe places to play, meet or socialise. Inner city development generally neglects to provide any green spaces and all Australian city centres experience significant heat island effects.
Adelaide has a Mediterranean climate with warm to hot summers and cool winters. It is subject to ‘cool changes’ when temperatures can plummet from the high 30s to low 20s in less than an hour. Heating is required in the winter months and cooling in the summer months.
Christie Walk is an ‘eco-city’ infill development in Adelaide, South Australia. It consists of 14 dwellings, which include four linked three-storey townhouses made of aerated concrete blocks, a three-storey block of 6 apartments, 4 standalone straw-bale cottages and community facilities. A further 13 apartments are currently under construction in a five-storey apartment block that incorporates a small community hall, kitchen and toilets. It is due for completion in June 2006. The project is on a T-shaped 2,000 m2 infill site. All dwellings are of the highest ecological standard, with both active and passive solar heating. The building designs take advantage of high thermal mass and extensive insulation. The dwellings rely on a natural ventilation system and are provided with no mechanical means of heating or cooling other than ceiling fans. There are also roof and community gardens. Storm water is used for irrigation and toilet flushing and non-toxic materials are used for construction. Black water will eventually be treated on site in a chlorine free system and directed to a nearby public park for irrigation. There is unrestricted access to the community.
Urban Ecology Australia set up the not-for-profit Wirranendi Housing Cooperative to own the land during construction and individual properties were then sold on a community title. Each purchaser owns their own dwelling but also shares ownership and responsibility for the landscaped community areas. The site is within walking distance of Adelaide’s Central Market and a full range of public transport services. It has reduced car park provision and there is no internal traffic. Those purchasing are individuals committed to ecological design principles and include first time home buyers, investment purchasers, experienced homeowners seeking the advantages of an urban lifestyle and older people wanting to retire in the context of an active, mixed community.
The owners have been attracted to and support the project because of its wider goals. A few of the owners are currently renting their property to families on lower incomes. . The project has tried to develop a model of community politics that recognises shared interests and collective effort despite operating within an economic system that has traditionally relied heavily on private ownership and profit making.
House prices are similar to those in the locality. The non-profit structure of the development cooperative and building company was an essential part of keeping house prices in a range comparable to conventional inner-city properties in Adelaide.
Residents and local community volunteers were involved throughout all planning and design stages as well as the construction processes. Through this process, the residents have acquired knowledge and expertise of development and financial mechanisms of the project. Local volunteers have also been involved throughout the project in addition to those who now live in the dwellings. The design of the project encourages social interaction through the incorporation of pedestrian paths and meeting places within the development.
All construction materials and finishes have been selected for their non-toxicity, including paints, stains, varnishes and glues. No formaldehyde has been used in the project to date and PVC has been avoided as much as practicable with most plumbing in polythene and some in copper.
Apart from a grant from the federal government for the initial sewage treatment system, all funding for Christie Walk has come from the personal savings and ethical borrowing, notably the Community Aid Abroad Ethical Investment Trust and Bendigo Community Bank. Residents are responsible for on-going management of the properties. House prices which include all the community areas and facilities range from A$150,000 (US$115,000) to over A$400,000 (US$306,000). The house prices are comparable with similar size properties in the area.
Funding for future stages of the project is now being provided by a mixture of community investment and commercial enterprise through a joint venture between Wirranendi Inc. and EcoCity Pty Ltd. Although construction costs have been contained within reasonable expectations, development related costs escalated when the project was delayed. Sound project management has ameliorated but not entirely eliminated those years of slow progress during the development phase.
The first stage of 14 houses was completed and occupied in 2002. The final stage of 13 dwellings and community buildings is due for completion in 2006. There were plans for a possible further development but shortage of capital and local development conditions now make this unlikely to eventuate.
Why is it innovative?
- Ecological community oriented development in an urban setting.
- Energy and water saving.
- Use of ethical finance.
- Non-toxicity of construction materials used.
What is the environmental impact?
The dwellings have a planned lifetime of 100 years rather than 25, which is the norm in Australia. Extensive use has been made of recycled materials. Brick and stone from demolished buildings on site have been re-used in the construction as well as the use of straw bale for part of the construction. Fly ash has been used in concrete and recycled timber in the windows.
The project is predicted to produce more energy than it uses. Natural cooling systems are used with stairwells acting as ventilation flues and water use is limited by low flow showerheads and low energy/water use appliances. All water caught by roofs, balconies and other impervious surfaces is collected, filtered and used for irrigation and toilet flushing.
It was intended that greywater be re-used and blackwater treated but there were technical problems with the original system. A new on-site sewage treatment system is now being planned in partnership with the state water utility, SA Water, and the Adelaide City Council. It is anticipated that surplus energy generated by the photovoltaics will be sold to the grid. Tours are held regularly for raising awareness of the energy conservation issues that need to be addressed both locally and globally, as well as giving an example of how these issues can be addressed.
Is it financially sustainable?
All development is privately funded through the ethical banking system. Fuel costs for both heating and cooling) are 50 – 90 per cent lower than average. Purchase costs were kept down by the not-for-profit structure and the volunteer labour that kick-started the project.
What is the social impact?
The project has always enjoyed support at the immediate neighbourhood level, possibly because the local community was informed about the project from the very early stages. The project exists because of an active community of committed individuals, all from diverse backgrounds who are equally interested in creating healthier, ecologically responsible futures.
- Surprising little difficulty was experienced in persuading planners and building departments to accept unconventional water and sewage treatment systems.
- Tensions often existed between the democratic co-operative approach to the development and the need for more immediate entrepreneurial decision making.
- Reliance on the membership to volunteer the skills required to create the development led to unevenness and inconsistencies that were acceptable at the community level but which eventually meant organisational and financial shortfalls in the delivery of the project.
- Difficulty experienced in sourcing recycled materials locally.
- The importance of understanding of the financial ground rules for development.
- Clearly delegating areas of responsibility and having clear boundaries between different organisations.
- The importance of building in sufficient profit margins to ensure creditworthiness.
- The business case must be examined objectively to fairly and evenly spread the financial responsibilities.
- Independent project management provides an effective route towards balancing community and business interests.
Places and spaces are generally quieter, with low running costs and genuine community/village atmosphere that finds expression in a number of ways.
Working examples are powerful tools to change public perceptions and aspirations, and to inform and change industry practices. Regular site visits are available to members of the public as well as Open Days and many individuals have been influenced after visiting or reading about the project. School and civic groups (including overseas delegations) also make regular visits.
Adelaide University has set up energy monitoring devices both within the homes and on the roof garden and an independent research study was undertaken on energy use of a sample of the dwellings.
The built form of Christie Walk has influenced community oriented design approaches both locally and nationally. The Aldinga EcoVillage with 142 lots on a greenfield site has been inspired by the experience at Christie Walk which has broken the mould of development in Adelaide. They have also been able to learn from the organisational and financial problems that the project has had to face.
It has been used nationally by the Canberra Co-Housing Association which is developing a similar project for 25 – 30 households in a suburban site in Canberra.
CBO, Local Community