Sustainability

amoeba: Difflugia sand grain housing

A creature that uses it's surrounding local environment to shape it's own dwelling.

Our Built Environment

All building work has an effect on the environment. Unlike the above Amoeba, every stage of our building's life results in pollution to a greater or lesser extent. We need to consider what materials we use, how we build, how the building effects the occupiers, how it effects the environment and what happens when the building is demolished.

Building and construction has an unhealthy appetite for energy and resources. 7% of UK primary energy demand is used for construction materials (9% of CO₂ production). Domestic heating, lighting and cooking is responsible for around 30% of UK energy demand and CO₂ emissions. Around 115,000 kWh of embodied energy are used in the materials, transportation and building of a typical 100m² masonry house, but this is just 5% of the energy needed to power the house during its life. If we get the design right, the potential for energy and resource savings are massive. A low energy timber- frame house can halve both figures easily! The 7.5 tonnes of CO₂ per year created by an average house could be cut by 50% if we adopted simple established energy conservation techniques. Government forecasts of climate change - higher winds, temperatures and increased flooding are already part of our experience, so CO₂ reduction must be the priority.

A sustainable balance between the reasonable requirements of people and nature lies at the heart of environment conscious building. We must take care of the natural world and use its resources wisely because we are totally dependent on its survival. Quality of life for people results from a sustainable, fair and healthy society, working in harmony with nature.

The barriers to sustainable building are bureaucratic and cultural rather than technological. We already have the techniques and materials but cannot let go of the past and turn our fear of the future into a positive move to a better world. Current planning practice stifles aesthetic quality, innovation and choice. Imagine automotive designers being required to make energy efficient cars with traditional classic styling! When compared to other countries in Europe, a recent study showed the UK to be close to bottom in a range of indicators for sustainable housing practice, with Denmark scoring around 69% higher. While other countries care about energy efflciency and emissions, environmental design and aesthetic quality, we seem content with inefficient little houses, so closely packed that there is no room for trees or nature.

All too often, the barren road and pavement dominate the layout, while the houses are 'clad' in odd-coloured bricks and with 'mock' cultural references from the past. The building site becomes a massive permanent disruption of local ecology.

The majority of houses are built for questionable motives, and allow people very little choice or freedom. This, plus the high cost of land and the techniques used, make houses the most expensive single purchase of a lifetime. Everything we do has both good and bad effects and in order to pay for housing, jobs are created which often have a negative effect on the environment. So, can we build housing that is more responsive and adaptable to our changing needs and at lower cost both financially and environmentally? The answer has to be yes - we already know how to do it - and we need to start doing it now.

The "Three-legged Stool" Principle

	This is a model which demonstrates the balance required between the elements of a community to achieve a sustainable way of living. These diagrams show the links between aspects of society. An imbalance of these elements can be better pictured by instability of a three-legged stool that is missing a leg. All projects to do with communities should be based on a three-legged stool approach. The three legs represent the Physical, Cultural and the Financial Aspects of projects - all of which must be in place or the stool falls over. Often development projects have a tendency towards dealing with the physical aspects only and assuming everything else will just happen. It is crucial that involvement with community development and regeneration, addresses the whole gamut and the seat which represents the local environment stays in balance.

The Matrix Model

Using the three-legged stool principle in the urban environment, a more complex picture is formed. As so many of the aspects of urban communities are interlinked in more dependent ways than smaller communities.

Key Points for Sustainable Building

Energy

The facts about CO2 emissions and the 'greenhouse' effect are well known. Vast amounts of energy are consumed in the production of building materials and during the life-time of the building. Select materials and products which use least energy in manufacture (natural or near natural) or that can be recycled or are recycled. Ensure buildings are insulated to the highest possible standards. This will reduce fuel bills. When designing a new building take advantage of the sun's free energy. Site orientation and the use of more glazing can make the best use of passive solar energy. Where possible investigate and consider using alternative, renewable forms of energy such as active solar, bio-fuels and power from wind and water.

Resources

Many materials used in building are from finite sources so it is important to use those that are sustainable. Timber and bio-crops (straw etc) are generally considered to be the most renewable resource provided they are grown and harvested in a sustainable way. Timber can also be recycled and re-used. You can help by asking for timber and wood products that bear the FSC (Forest Stewardship's Council) logo which is an independent, international and credible labelling scheme for timber and timber products.

Atmosphere

The damage to the ozone layer caused by CFC's and HCFC's has been recognised for many years. The problems associated with CFC emissions have been addressed by international intergovernmental agreements. However some insulations use HCFC's which although having a lower ozone depletion potential, do have a very high global warming potential. Alternatives such as cellulose, cork and foamed glass are available and should be used.

Health

It is well known that exposure to chemicals can cause damage to human health and the environment. Hazardous chemicals are found in many products such as timber preservatives, paint and stains, etc. There is still excessive emphasis on treating timbers. For example, most banks, buildings societies and local authorities still insist on extensive chemical treatment of existing wood worm when providing loans or grants.

Sustainable Building Criteria

Avoid damage to people and the environment: use local renewable natural materials and resources; reduce emissions and non-degradable waste; minimise the use of materials and energy; select materials which combine useful properties; design with site and climate; design for low cost, adaptability and recycling; adopt holistic thinking and design principles; protect and encourage biological diversity. Local design and construction to sustainable criteria will directly benefit local economies and will reducetransport and environmental costs. Since we live in a changing world, it is sensible to design buildings which can be recycled, so that materials and foundations can easily be reused and land is not degraded or polluted.

A Worm's Eye View of an Urban Community

Urban sustainable development requires us to look at the regeneration of the built environment from a different perspective. Good infrastructure installed at the initial stages of developmment is necessary for any degree of sustainability.