The construction and demolition sector is the largest contributor of waste in the UK, responsible for generating 120 million tonnes of waste every year – around one third of all waste in the UK. But great progress is being made.
In the UK, we generate more than 434m tonnes of waste every year. According to DEFRA, the total quantity of waste produced (household and municipal) in the UK has fallen from 27.33m tonnes to 26.89 m tonnes, or 1.6 per cent, since 2008. In addition, the quantity of waste sent to landfill has decreased and recycling increased.
In spite of these positive indications, Waste Watch suggests that 54 per cent of our waste is still being sent to landfill, over 80 per cent of waste that could be recycled is not, and valuable raw materials continue to be consumed at an unsustainable and environmentally destructive rate.
In 2010 government statistics suggested that the construction industry produced in excess of 47 million tonnes of waste from construction and demolition processes. As a major resource generator, consumer and producer of waste, it is crucial that the construction industry finds a means of designing, building and managing waste that will allow it to meet government targets and contribute to the sustainability agenda.
The waste hierarchy is now a well-recognised approach to managing waste. The hierarchy is as follows:
- Preparing for re-use
- Other recovery
The 2008 Strategy for Sustainable Construction found that over 25 million tonnes of construction, demolition and excavation waste ends up in landfill every year. As a major resource consumer and producer of waste, it is crucial that the construction industry finds a means of designing, building and managing waste that will allow it to meet government targets and contribute to the sustainability agenda.
Resource efficiency - Prevention
In 2008 BRE and Defra funded the development of the Construction Resources and Waste (CRW) roadmap, with the objective to present a longer term perspective and vision for improving construction resource use and waste. The intent of the process was to define priorities for further work and action with subsequent action plans being more focussed on specific objectives/ sectors. This work then transitioned into other initiatives such as the Resource Efficiency Action Plans which were developed with industry and WRAP.
The UK-GBC Sustainable Community Infrastructure Task Group identified some of the most beneficial alternative methods of waste management and reduction. These include waste collection systems, diverting waste away from landfill and recovering energy from waste.
The Construction waste strategy for England is now the Construction 2025: Industrial strategy for construction – Government and industry in partnership. In this document the Government set out the benefits of offsite construction as a method for significantly reducing construction waste (statistics suggested the waste could be halved). The Government Green Construction Board (GCB) are working to drive procurement efficiency and explore options for further efficiency gains in the procurement process with expected targets to be outlined in due course.
The GCB are working to drive forward the actions set out in the Low Carbon Construction Action Plan, which includes the within its remit issues associated with waste.
Waste Strategy for England 2007, states that by 2012, there will be a 50 per cent reduction of construction, demolition and excavation (CD&E) waste to landfill compared to 2008. The Strategic Forum are taking this work forward.
Re-use and recycling
In order to divert waste from landfill, one concept that has been developed is the circular economy which is an alternative to a traditional linear economy (make, use, dispose). It encourages industry to keep resources in use for as long as possible, extract the maximum value from them whilst in use, then recover and regenerate products and materials at the end of each service life. There are several reports which provide guidance on employing this approach, which include the Aldersgate Group’s Report: “Resilience in the Round”.
Some manufacturers also offer something called a take back scheme, and are encouraged to use reclaimed building materials. Design teams can also use concepts such as ‘design for de-construction’ in order to reduce wastage.
Waste to energy - Recover
The most significant, long-term opportunity to improve waste management processes and reduce carbon emissions comes from the recovery of energy from waste. The government has pledged to ensure that energy is recovered from 25 per cent of the waste we produce by 2020.
The UK Biomass strategy report published in 2007 indicated that there are approximately 24 million tonnes per annum of biomass within the waste stream which is appropriate for fuel use (compared with 2 million tonnes per year of clean wood in England and Wales). The more recent UK Bioenergy Strategy report published in 2012 indicates that by 2020, between 8-11% of the UK’s total primary energy demand will be met by bioenergy and by 2050 could be 12%.
Up until now, local authorities and industry have perceived waste to energy plants as unpopular with the public. However, research conducted by a UK-GBC Task Group (UK GBC Consumer Perceptions survey, Appendix G) reveals that 71 per cent of consumers found them acceptable. The UK-GBC Task Group concluded by urging local authority waste managers to conduct carbon flow analysis when procuring waste contracts, to commit to a common methodology on the valuation of carbon, and to identify the optimum locations for waste to energy plants.
Additionally, the Defra has now published a guide for businesses to identify opportunities in energy from waste. Read more here.
Diverting construction waste from landfill - Disposal
The European Landfill Directive states that England and Wales must landfill no more than 12 million tonnes of biodegradable municipal waste by 2009/10, 8 million tonnes by 2012/13 and 5.5 million tonnes by 2019/20. The Directive has led to a significant reduction in the use of landfill sites and an increase in recycling and composting, due to increasing landfill taxes and gate fees. In 2010, 19 million tonnes of commercial and industrial waste were sent to landfill, compared with nearly 24 million tonnes in 2008. See more here.