While other sectors are reducing their consumption and generating less waste to meet carbon emission targets, the construction sector seems to be the most resilient. lagging behind. This is particularly concerning considering that it’s responsible for 38%global greenhouse gas emissions 62% of the UK’s waste.
The UK Green Building Council (UKGBC), has announced a new roadmap to address construction’s carbon emissions at the UN climate summit COP26. This includes calls for more reuse of existing buildings as opposed to building new ones – something my research suggests is vital.
You’d be forgiven for thinking that many new buildings in the UK are created sustainable. It’s difficult to find a new build that doesn’t claim to be “green”, “eco” or “low-carbon” these days, with over 540,000 buildings now having a BREEAMSustainability rating applauds their environmental performance.
The issue is that most sustainability award schemes place their emphasis on “operational emissions“associated with a building’s use, like lighting, heating and electricity. This means that a new building that is well insulated, has an efficient heating system and uses energy-saving light bulbs will be labelled “sustainable”, regardless of whether its construction was environmentally friendly. What’s more, if this building has bike storage and electric vehicle charging points, its rating is likely to be even higher – even if they are never actually used.
Of course, it is easy to forget about the carbon footprint that was created by the building itself. This is called “embodied carbon”, and refers to emissions from extracting and transporting materials, constructing buildings, and eventually demolishing them.
Embodied carbon emissions could be a representation of up to 70% of a building’s carbon emissions over its lifetime – a figure that will grow as operational energy is increasingly generated from renewable sources. More than half of a building’s lifetime carbon footprint can be emitted before it is even occupied.
To put into perspective the importance and importance of embodied Carbon, an office housing 750 people could produce 10,000 tonnes of carbon. This is equivalent to taking 11,000 flights between London & New York, driving 30,000,000 miles in a car, and boiling a kettle 700,000,000 times. Despite this, unlike buildings’ energy performance (which has been regulated in the UK since the 1960sEmbedded carbon is still not regulated in the UK.
The importance of embodied carbon emissions were first recognised by the government earlier this year in their “Build Back Greener” net zero strategy, which alluded to planned introductions of embodied carbon reporting and regulation.
These suggestions do not focus on reducing the embodied carbon of new buildings. My research focuses on ways we can reduce embodied CO2 even further. reusing old buildings.
Reusing buildings falls within the spirit of a circular economy – an approach to production which aims to keep materials in use by extending product lifespans and looping waste back around as a resource. We’re already practising this with items like water bottles, coffee cups and carrier bags. These items have a much lower carbon content than buildings so reusing buildings offers a huge opportunity to save carbon.
It’s good news that the government is acknowledging the importance of reducing embodied carbon – and that organisations such as the UKGBC recognise how reusing buildings can help achieve this. Without policy backing, building reuse will not become a widespread practice. However, it is important to educate all those involved in building so that they can safely and skillfully reuse buildings.
Building reuse is the focus of my most recent work with the University of Sheffield’s Urban Flows Observatory. As well as how to drive reuse through policy change, my work focuses on educating the next generation of civil and structural engineers on how to reuse existing buildings – topics I feel are not adequately covered at university level. Assessment tools like “regenerate”, which I developed with the Urban Flows Observatory team, are also useful to help people design new buildings with the circular economy and future reuse in mind.
Time to make a change
Despite being increasingly recognized for the importance of embodied Carbon, the proposed UK regulations on the topic are unlikely to make a significant impact. net zero targetsBy 2050. This is because they are more concerned with reducing embodied carbon in new buildings than repurposing existing ones.
These are the suggested measures UKGBC’s roadmapThey have made some progress in addressing this problem, but now the government must adopt them to make changes in construction in the country. The widespread adoption of policies for construction such as those of the Greater London Authority – which promote building reuse and ensure that any newly constructed buildings are reusable in the future – would be a good first step.
The UK’s tax system favors new builds. zero ratedFor VAT. This is a key step to encourage retrofitting and refurbishment rather than demolition.
If the construction industry is to meet its potential, decarbonisation targetsYou can help limit global temperature increases by contributing to it 1.5°CIt is time to stop destroying buildings and replacing them in new ones. Instead, we should begin to use the carbon from the past to prevent the emission of more.