Buildings impact upon the environment in many ways. Current designs demand vast quantities of physical resources such as materials, energy and money in their construction, maintenance and use. They also can result in effects such as loss of amenity and biodiversity which are much more difficult to assess.
We need to build in an ecologically sustainable manner. It is therefore necessary to consider the impact of a building over it's entire " life cycle".
The life cycle of a building can have a number of stages, all of which need assessment prior to design and construction.
1. Mining and extraction / harvesting
2. Manufacture
3. Construction
4. Use
5. Demolition
The most important stages as far as environmental impact is concerned are
1, 2, and recently 5.
A Building Materials Assessment System based on life cycle analysis has been
developed to compare the ecological impact of various building materials.
The results below are based upon this Australian developed analysis tool.
Walls |
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Roofs |
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Floors |
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Note: The lower the figure the more environmentally friendly the product or system is.
Designers, builders and developers need to seek a balance between conventional requirements for ease of build, design and cost and the equally important consideration of the cost of the building to the environment.
In assessing and choosing materials consider the following:
1. Environmental factors
2. Local materials and transport costs
3. Needs of home owners
4. Appropriate building design for local area.
5. Cost of development
To assess the impact of each building material consider the following issues:
1. The damage to the environment during mining or harvesting of the basic material
2. The source size or renewability of the materials.
3. The recycle content.
4. Waste residue in the manufacture process
5. Air pollution due to manufacturing process
6. The volume of energy used in the manufacturing process.
7. The cost of transportation
8. The volume of energy used in the erection process
9. On site waste and packaging
10. Maintenance required and cost there off during the life span of the building
11. The volume and cost of energy required to demolish the building
12. The re-cyclibility of the materials used post demolition.