Today's so-called low-energy buildings consume more fossil energy than the average building constructed 25 years ago. They cause more car use, increase the consumption of raw materials and generate more waste. This can hardly be called sustainable.
But how do you define sustainable? Perhaps
the most commonly used definition is from
the international Brundtland Commission:
"A development that meets the needs of the present without compromising the ability of future generations to meet their own needs."
More applicable to construction is the "triple bottom line". This says that a sustainable development is one that delivers identifiable performance improvements according to social, economic and environmental criteria.
What is needed, however, is a definition that makes sustainable development different. Construction needs to address what is behind the words "triple bottom line".
A socially sustainable project must go beyond the usual client needs to address community needs and improve local quality of life. It should identify and plug gaps in the local community so that it integrates into, and reinforces, local life. Ultimately, it should enable the community to sustain itself indefinitely by empowering individuals and giving them more choice and control over their local work and home environments.
To be economically sustainable, a project must look beyond the client's narrow financial objectives and consider its long-term economic impact. In generating wealth, a sustainable project should stimulate local business, provide job opportunities and address employment deficiencies. It may also have a more indirect impact by assisting the financial viability of public transport systems.
To create environmental sustainability, material consumption needs to be substantially reduced, as does the pollution and waste these materials produce. This involves extending the life of buildings by reusing them, as well as sourcing non-polluting materials and recycling waste materials. This kind of sustainability must also address the indirect aspects of a project. For example, can people get to and from it without relying on a car?
So is the industry even capable of producing
Producing a truly sustainable development will probably involve a 90% reduction in resource and material consumption
a truly sustainable design or project – one that can be sustained almost indefinitely? Arguably, yes – the solution will probably involve about a 90% reduction in material and resource consumption and be community-driven,
instead of focusing on the product or on consumption.
Although there are buildings that address
parts of the triple bottom line, it is likely to take 50 years to develop the techniques and understanding to achieve it completely. Interestingly, according to the United Nations, this same timescale is predicted for the
world population to stabilise and for global resource demands to be fully considered. In the meantime, we are in a process best described as "development towards sustainability".
How can projects today address sustainability? The whole project team must first acknowledge the aims of the triple bottom line: identifiable improvements on social, economic and environmental issues. These issues should then be assessed in the context of the area. Remember,
it is the simultaneous improvement on all three aspects that makes a development sustainable; improvement on just one or two aspects is
This approach is called a "multispeed" sustainability response in technical jargon. This means that we are
all starting from different baselines and responding to different pressures in a broad range of business areas.
Chris Twinn is associate director of multidisciplinary consultant Arup