The production and use of building materials consumes large quantities of energy and resources and generates waste. The choice of materials used in a building therefore has important implications for the environment; wherever possible they should be selected to minimise negative environment impacts and the consumption of non-renewable resources.
A key concept when thinking about what materials to use is ‘life cycle stewardship’. This means that the consequences and impacts of using materials must be considered from the point at which they are mined/harvested, through processing and manufacture, to installation, use, reuse/recycling and disposal.
Key considerations regarding sustainable materials include:
- reused or recycled – where possible reuse materials or use recycled materials instead of new ones as this cuts out the emissions and energy consumption associated with producing new materials and reduces waste. For example, where demolition is involved, identify opportunities for reuse or recycling of demolition materials (e.g. use recycled aggregates in new concrete)
- low toxicity - use non-toxic materials that are free of harmful chemicals such as CFCs
- local sourcing – sourcing of materials locally may help to reduce the energy use and environmental impacts associated with transportation
- responsible sourcing - independent certification schemes exist to confirm that specific materials comply with responsible sourcing standards. For example timber from well-managed forests is certified by the Forest Stewardship Council (FSC).
- maintenance/replacement and durability – using materials that are long lasting and that are cheap and relatively easy to maintain, adapt and/or replace will ensure that buildings are flexible and built to last
- reusable or recyclable – select materials that can be easily dismantled and reused or recycled at the end of their useful life
The Building Research Establishment’s Green Guide provides a simple tool to enable the identification of the environmental implications of different materials choices. It measures and assesses a range of environmental impacts from “cradle to grave”, and offers a summary rating (A+ to E) indicating each material’s environmental impact.
Of all building materials, concrete deserves special mention because its production is highly energy intensive - some claim concrete production is responsible for 5% of the world's carbon emissions. Therefore where use of concrete is required it is important to consider the opportunities for using ‘greener’ forms of concrete such as by using ground granulated blast furnace slag (GGBS) cement and/or recycled concrete aggregates.
Islington Council encourages developers to achieve high levels of environmental performance in all developments through robust application of planning policies and promotion of relevant options and technologies. For example, we encourage developers to use low impact, locally and/or sustainably sourced, reused and recycled materials and to select major building components with high BRE Green Guide ratings. For more information see the Sustainable Design webpage.
Sustainable building standards such as the Code for Sustainable Homes and BREEAM also encourage sustainable use of materials. For more information on these standards see the downloadable document at the bottom of the page.