6.2 Environmental Impact of Construction Materials

 

 

6.2 Environmental Impact of Construction Materials

Building and construction activities worldwide consume 3 billion tonnes of raw materials each year, which is 40% of total global use. The UK's annual construction output requires 170 million tonnes of primary materials and products, 125 million tonnes of quarry products and 70 million tonnes of secondary recycled and reclaimed products. To manufacture and deliver these products, 6 million tonnes of energy are consumed and 23 million tonnes of C02 are emitted [see reference 2]. The main materials used in construction are steel and concrete, both of which have a high embodied energy.


The
choice of materials and building elements for any building will mainly be made on the basis of thermal properties, structural properties and cost. As well as the energy implications of the materials, other factors to be considered include:

  • the implications of mineral extraction to derive the basic product
  • the pollution and energy consequences of the manufacturing/production process
  • toxicity of product and chemicals etc. used in manufacturing process e.g. global warming potential/ozone depletion potential
  • waste issues at all stages of the production and construction processes
  • distribution/transport issues
  • life-cycle and recycling options at the end of its expected life


One measure often used to measure environmental impact is embodied energy. A number of Green Guides have been produced that include the above issues and attempt to provide some weighting on the likely impact of all the above [see reference 6].