Resource Consumption

Metal consumption continues to show exponential growth.

World steel consumption is growing at a reduced rate due to recycling. China is the major producer of crude steel.

Wood consumption has continuous growth. This has led to deforestation and therefore requires sustainable management to ensure the rate of use is not exceeded by regenerative capacity.

Construction materials are a significant part of the total material resource use around the world.

Life Cycle Impacts

• Unsustainable use of finite and renewable resources

• Hidden impacts - land (areas of land for storing materials), water (significant amounts of water use in the production of materials), transport, energy, waste disposal, and pollution

• Ecological impacts

Construction products have significant emissions, but much of it is ‘imported’. This means that the materials produced for the UK create emissions and therefore pollution around the world through transport, production, etc.

The impacts of production around the world can be positive or negative:

• Positive impacts of production around the world - infrastructure, jobs, restoration, safety, shelter, well-being, etc.

• Negative impacts of production around the world - land use, traffic, noise, etc.

Construction Aggregates

Construction aggregates make up the largest tonnage of UK construction materials, and have significant environmental impacts and opportunities, with a significant portion being from recycled or secondary sources.

Recycled aggregates - reused within the industry

Secondary aggregates - reused from another industry

There is a continuous growth of recycled and secondary materials use, especially in the UK, with around a third of aggregates in the UK from recycled sources in 2018.

Potential Barriers to Recycling

Technical

Design and specification might not allow the use of recycled material.

Knowledge and Experience - construction industry is quite traditional and many in the industry like to stick to old methods.

Standards do not discriminate between natural and secondary/recycled aggregates, so need to make sure the recycled perform the exact same.

There are specifications that tell us what materials can be used for different works.

Quality controls allow us to check recycled materials and see if they can be used as normal - this increases confidence in performance, and the fully recovered product is no longer a waste. Refer to the Environment Agency Quality Protocol document for Aggregates from inert waste - which provides a flow chart for checking.

Case studies:

• BP Amoco Development - contractors were obliged to segregate waste, used SWMPs, materials sourced from suppliers with little packaging, reduced waste and excellent BREEAM rating; this all led to financial benefits.

• Channel Tunnel Rail Link - used sustainable and recycled aggregates, very cost-effective and lots of money saved.

Non-technical

Planning permission is required for recycling facilities.

Investment is needed for building recycling facilities and transport from where it is.

Procurement - client and designer need good knowledge.

• Case study: Olympic Delivery Authority - sourced and used environmentally and socially responsible materials, reduced waste from demolition at the design stage as many buildings needed won’t be used again, many materials used were already recycled or used previously, and timber was sourced from sustainable sources with clear supply chain evidence.

Cost - needs to be profitable in the long run. Fiscal policy can be used as a solution to this - e.g. Aggregate levy and Landfill tax. See Case studies in the previous section on money savings from recycling.

Supply - access is required to these materials, and if it is too far away then the transport of the materials could jeopardise the benefits.

Waste - waste hierarchy and national planning policy for waste (2014) can be used to encourage the use of recycling and reuse. Includes identifying needs and suitable sites for facilities, planning applications and monitoring and reporting.

Site Waste Management Plans

A living plan that details the amount and type of waste that is estimated to be produced on a construction site, and how it will be reused, recycled or otherwise disposed of.

In 2008, was required on all projects over a certain cost, but this was repealed in 2013. It is still a requirement of sustainability assessment tools and some planning authorities.

Prevents illegal dumping of waste, and ensures it is handled by registered waste carriers responsibly.

What is done in an SWMP:

• Identify waste reduction options and waste streams that can be recovered.

• Agree on recovery rates and waste reduction options for demolition or construction.

• How recovery rates will be met.

• Measure waste and compare it to recovery rates.

• Improve performance if targets are not being met.

• Appoint contractors for measuring, managing, monitoring and reporting on waste.

Circular Economy

A circular economy is a model that aims to decouple economic growth and development from the consumption of finite resources. A circular economy is restorative, aiming to keep products, components and materials at their highest utility and value, at all times.

A circular economy is about optimising systems rather than components, including careful management of materials:

• Technical cycles - materials are maintained, reused, refurbished and recycled (at last resort)

• Biological cycles - nontoxic materials are cascaded and eventually returned to the soil, restoring natural capital

Reuse of products - there is more potential for reuse than is currently being done.

Reuse of buildings - don’t demolish old buildings, integrate them into designs if possible. E.g. George Green Library.

‘Product as a Service’ business model - don’t sell the product, sell the service of lending the product, then take it back to reuse parts or fix when broken. E.g. Rolls Royce doesn’t sell the engine.

Challenges of Circular Economy:

• Lack of knowledge and information

• Design for disassembly or refurbishment

• Storage space

• Quality control or recertification of structural elements

• Procurement

• Performance targets

• Long Design Lives

• Different owners and users - all must be interested in life cycle performance