Dr Ken Yeang is one of the world’s leading architects. Here are his views on architecture for the serious challenges that lie ahead for the planet and design…
Providing ecological corridors and linkages in regional planning is crucial in making urban patterns more biologically viable.
We must biologically integrate the inorganic aspects and processes of our built environment with the landscape so that they mutually become ecosystemic. We must create “human-made ecosystems” compatible with the ecosystems in nature. By doing so, we enhance human-made ecosystems’ abilities to sustain life in the biosphere.
Understanding the ecology of the site
Ecodesign is also about discernment of the ecology of the site. Any activity from our design or our business takes place with the objective to physically integrate benignly with the ecosystems.
We must first understand the locality’s ecosystem before imposing any human activity upon it. Every site has an ecology with a limiting capacity to withstand stresses imposed upon it, which if stressed beyond this capacity, becomes irrevocably damaged. Consequences can range from minimal localised impact such as the clearing of a small land area for access, to the total devastation of the entire land area such as the clearing of all trees and vegetation, levelling the topography, diversion of existing waterways, etc.
To identify all aspects of this carrying capacity, we need to carry out an analysis of the site’s ecology.
We must ascertain its ecosystem’s structure and energy flow, its species diversity and other ecological properties. Then we must identify which parts of the site, if any, have different types of structures and activities, and which parts are particularly sensitive. Finally, we must consider the likely impacts of the intended construction and use.
This is, of course, a major undertaking. It needs to be done diurnally over the year and in some instances over years. To reduce this lengthy effort, landscape architects developed the sieve-mapping technique for landscaping mapping.
As we map the layers, we overlay them, assign points, evaluate the interactions in relation to our proposed land use and patterns of use, and produce the composite map or guide our planning, for instance, the disposition of the access roads, water management, drainage patterns and shaping of the built form(s).
We must be aware that method generally treats the site’s ecosystem statically and may ignore the dynamic forces taking place between the layers and within an ecosystem. Between each of these layers are complex interactions. Thus, analyzing an ecosystem requires more than mapping. We must examine the inter-layer relationships.
Designing for low energy systems
We must also look into ways to configure the built forms and operational systems for our built environment and our businesses as low-energy systems.
In addressing this, we need to look into ways to improve internal comfort conditions. There are essentially five modes: Passive Mode or bioclimatic design, Mixed Mode, Full Mode, Productive Mode and Composite Mode.
Designing means looking at Passive Mode strategies first, then Mixed Mode to Full Mode, Productive Mode and to Composite Mode, all the while adopting progressive strategies to improve comfort conditions relative to external conditions.
Meeting contemporary expectations for comfort conditions, especially in manufacturing, cannot be achieved by Passive Mode or by Mixed Mode alone. The internal environment often needs to be supplemented by using external sources of energy, as in Full Mode.
Full Mode is the full use of electro-mechanical systems, as in any conventional building, to improve the internal conditions of comfort. This often requires use of external energy sources (whether from fossil-fuel derived sources or from local ambient sources.
If our users insist on having consistent comfort conditions throughout the year, the designed system heads towards a Full Mode design.
Ecodesign of our buildings and businesses must minimize the use of non-renewable sources of energy. In this regard, low-energy design is an important objective.
Passive Mode is designing for improved comfort conditions over external conditions without the use of any electro-mechanical systems. Examples of Passive Mode strategies include adopting appropriate building configurations and orientation in relation to the locality’s climate, appropriate façade design solid-to-glazed area ratio and suitable thermal insulation levels, use of natural ventilation and use of vegetation.
The design strategy for the built form must start with Passive Mode or bioclimatic design. This can significantly influence the configuration of the built form and its enclosural form. Therefore, this must be the first level of design consideration in the process, following which we can adopt other modes to further enhance the energy efficiency.
Passive Mode requires an understanding of the climatic conditions of the locality, then designing not just to synchronize the built form’s design with the local meteorological conditions, but to optimize the ambient energy of the locality into a building design with improved internal comfort conditions without the use of any electro-mechanical systems.
Mixed Mode is where we use some electro-mechanical (M&E) systems. Examples including ceiling fans, double facades, flue atriums and evaporative cooling.
Productive Mode is where the built system generates its own energy (e.g. solar energy using photovoltaics, or wind energy).
Ecosystems use solar energy, which is transformed into chemical energy by the photosynthesis of green plants and drives the ecological cycle. If ecodesign is to be ecomimetic, we should seek to do the same.
In the case of Productive Modes, such solar collectors, photo-voltaics and wind energy, these systems require sophisticated technological systems. They subsequently increase the inorganic content of the built form, its embodied energy content and its use of material resources, with increased attendant impacts on the environment.
Composite Mode is a composite of all the above modes and is a system that varies over the seasons of the year.
It must be clear now that low-energy design is essentially a user-driven condition and a lifestyle issue. We must appreciate that Passive Mode and Mixed Mode design can never compete with the comfort levels of the high-energy, Full Mode conditions.
Recycling and waste
Ecodesign also requires the designer to use green materials and assemblies of materials, and components that facilitate reuse, recycling and reintegration for temporal integration with the ecological systems.
We need to be ecomimetic in our use of materials in the built environment. In ecosystems, all living organisms feed on continual flows of matter and energy from their environment to stay alive, and all living organisms continually produce wastes. Here, an ecosystem generates no waste, one species’ waste being another species’ food. Thus matter cycles continually through the web of life. It is this closing of the loop in reuse and recycling that our human-made environment must imitate.
We should unceremoniously regard everything produced by humans as eventual garbage or waste material. The question for design, businesses and manufacturing is: What do we do with the waste material?
If these are readily biodegradable, they can return into the environment through decomposition, whereas the other generally inert wastes need to be deposited somewhere, currently as landfill or pollutants.
Ecomimetically, we need to think about how a building, its components and its outputs can be reused and recycled at the outset in design before production. This determines the processes, the materials selected and the way in which these are connected to each other in manufacturing and in our built form.
For instance, to facilitate reuse, the connection between components in the built form and in manufactured products needs to be mechanically joined for ease of demountability. The connection should be modular to facilitate reuse in an acceptable condition.
Integration with nature
Another major design issue is the systemic integration of our built forms and its operational systems and internal processes with the ecosystems in nature.
This integration is crucial because if our built systems and processes do not integrate with the natural systems in nature, then they will remain disparate, artificial items and potential pollutants. Their eventual integration after their manufacture and use is only through biodegradation. Often, this requires a long-term natural process of decomposition.
While manufacturing and designing for recycling and reuse within the human-made environment relieves the problem of deposition of waste, we should integrate not just the inorganic waste, such as sewage, rainwater runoff, wastewater and food wastes, but also the inorganic ones as well.
We might draw an analogy between ecodesign and prosthetics in surgery.
Ecodesign is essentially design that integrates our artificial systems both mechanically and organically, with its host system being the ecosystems. Similarly, a medical prosthetic device has to integrate with its organic host being – the human body. Failure to integrate well will result in dislocation in both.
By analogy, this is what ecodesign in our built environment and in our businesses should achieve: a total physical, systemic and temporal integration of our human-made, built environment with our organic host in a benign and positive way.
Discussion here on some of the key issues will help us approach the ecological design of artifacts and our businesses to be environmentally responsive.
There are of course other aspects. There are still a large number of theoretical and technical problems to be solved before we have a truly ecological built environment.
Ken Yeang © 2008
Note: The above essay is expanded in the new book authored by Dr. Ken Yeang, Ecodesign: A Manual for Ecological Design, published by John Wiley & Sons (2006) . The book contains most his recent theoretical work, technical interpretations, design ideas and notes for future work. The book can be viewed at www.amazon.com and is available in Australian bookshops.(see our the review by Rand Ekman)
Dr Ken Yeang is an architect-planner, ecologist and author best known for his signature and innovative green buildings and masterplans. He is regarded as one of the foremost designers and noted authority on ecologically-responsive architecture and planning. He is a principal of London based architectural firm Llewelyn Davies Yeang and Malaysian based T.R Hamzah & Yeang.