Buildings currently use nearly half the total energy consumption of the developed world with artificial lighting and air-conditioning being the biggest culprits.

With natural ventilation people accept, even enjoy, more widely fluctuating temperatures in buildings ventilated by passive systems, especially when under personal control, eliminating the defined comfort standards of mechanical systems.

Incorporating light shelves and reducing deep spaces in a building can reduce or eliminate the use of artificial light.

In climates where some mechanical input is necessary the energy use can be minimised by the use of ambient energies such as solar, use of ground water, or of evaporative cooling. The time honoured provision of overhangs to a building maintains optimal conditions as seasons change.

Focus on the use of non-depletable ambient energies and replenishable or near inexhaustible materials will curb the escalating impact of the over-use of fossil fuel derived energy on the environment.

Non-depletable ambient energies include sun, wind, waves and gravity (hydro-electricity). Designed well a building can harness the ambient energies around them, and in fact a building already stands to generate more energy than they use. Such excesses can be stored or passed on to others.

Although difficult for all buildings to totally use replenishable or near inexhaustible materials, such as wood, mud, clay and recycled materials, these can be incorporated into a building to encourage sustainability.

The efficiencies of organic cycles in nature, where the waste of one creature or process becomes the nutrient of another, are impressive. Although a hard act to follow these templates can be used to reduce the burden of waste and toxic pollution particularly related to the building industry.

The re-use of an existing building or its components is one of the most simple and obvious forms of re-cycling. The future need to recycle can be incorporated into the building design. Such buildings are referred to as a loose-fit building. Coupled with the re-use of grey water, the storage of rainwater, and the re-use of heat, a modern building can become an artificial interface with nature.

Many modern materials currently in use are both toxic in their manufacture and when installed. With careful selection of materials these high levels of waste and pollution can be significantly reduced.

Embodied energy includes all the energy required to extract, manufacture and transport a material along with the energy to assemble and finish the material in a building.

The material with the least embodied energy is wood followed by concrete (in contrast to aluminium which has an embodied energy 126 x that of wood). This fact reinforces the advantages of recycling wood from existing structures and embracing the concept of loose-fit buildings. Other considerations such as the use of locally sourced materials all contribute to a reduction of embodied energy in the materials selected for a building.

Long life, loose fit buildings have attributes such as adaptability, are accommodating, dignified, hospitable, and are relatively timeless. They steer away from being merely utilitarian and gratuitously fashionable (and soon passé).

To design a loose-fit building gives consideration to the legacy of future generations. These buildings lend themselves to being conserved which in turn increases the returns on the initial investment as well as the obvious benefits of conserving nature and energy. Historic buildings are inherently long life, loose fit buildings. They have repeatedly displayed an ability to be adapted to the changing needs of society. They were built with materials that lasted and often improved visually with age.

This is a departure from costing on a narrowly economic manner. It involves a holistic approach that includes the costs applied to the building for its life time and beyond.

As well as utility and maintenance costs it includes costs to society, individuals, ecology and the larger environment. When applied it illustrates that the initial capital cost is only a fraction of the total costs of the building.

Although this may sound lofty thinking in the current consumerist society, total life costing as an ideal is already being adopted in progressive societies such as Scandinavia. Once embedded in our thinking this holistic approach to architecture sets us firmly on the path to a 'built' ecosystem.

Consideration of the context of where a building sits is fundamental to our design approach. Instead of being conceived as a stand alone object this approach to design goes some way towards creating a symbiosis between the building and its setting to ensure minimal negative impact.

Consideration of the context of where a building sits is informed by knowledge of the place, building traditions and local materials as well as rigorous surveys and use of technologies for predictive analysis of ecological conditions.

We have all heard of the 'sick building syndrome'; where a building is constructed from toxic materials, uses artificial light, mechanical air-conditioning, and has no access to natural light or fresh air. Not only are these psychologically and physically unhealthy they are not cost effective to operate and are harmful to the ecosystem.

The creation of 'green' architecture is more than just a technical issue, it embraces the concept of health and well-being of the occupants, relationships to the community and reduced impact to the ecosystem. Buildings can be part of a much enhanced quality of life with the capability of a long life and a gentle touch on the environment.

The role of architecture to bring about a sustainable culture, a change in the inherited mindset, is not to be underestimated. Most people today interact with a building in their day to day life.

The considered design of a building can strongly assist the regeneration of a sense of community and connection to the natural world. How a community functions can be designed in to all levels of the built environment. A building can assist in the education of people to make them more sensitive to nature and increase their sense of connection with other people.

Obviously this role extends beyond the architect to urban planners and decision makers on many levels. However choices people make every day concerning even the smallest of buildings all form part of the greater built environment.