Paul Astle is Building Structures Sustainability Lead at Ramboll
As an industry, we don’t know how exactly much concrete we use. While the Materials Product Association (MPA) estimates that 37.5 million cubic metres of concrete are used each year across the UK, the reality is that we don’t have a detailed understanding of how much of a given type of concrete is used, where it is used, and the embodied carbon associated with it. However, we do know that we use a lot of concrete and that cumulatively this is a significant contributor to carbon emissions, resource use, and waste generation.
Many efforts are underway to tackle the stubborn emissions associated with the built environment and concrete in particular. But there is a lack of data in relation to the different concretes used, whether they used any cement replacements, and how this varies across projects and regions. We need to develop a greater understanding of how and where we use concrete and what it is made up of, including its embodied carbon. Armed with this information, we can then help ensure that the industry responds in a coordinated manner by sharing best practice and scaling up suitable technologies, which may vary depending on the project.
The Climate Group’s ConcreteZero initiative, of which Ramboll is a founding member, intends to send a powerful signal into the concrete supply chain for lower carbon and, ultimately, net zero carbon concrete. Members of the initiative commit to track and report detailed information on the concrete they specify and procure and will begin to limit the amount of carbon in that concrete, with an ultimate target of all procured concrete being net zero by 2050.
It is incredibly important that we not only record but share this information about the concrete we use. ConcreteZero members will benefit from a better understanding of the concrete they specify and procure, allowing them to focus and refine their own efforts at carbon reduction. Moreover, the whole industry will benefit from sharing this data, which will allow improvements in industry benchmarking and identification of opportunities to make savings. This change in attitude is perhaps analogous to the late Mikhail Gorbachev’s glasnost, or openness. We need to prioritise sharing of information that will allow industry-wide carbon reduction, instead of data protectionism or worse, apathy.
It is recognised that this is a challenge. We need a change in attitude and a significant effort to standardise concrete records. While concrete data is generally recorded on construction sites, for commercial reasons if nothing else, it is rare that it would find its way back to the ultimate client. As well, the format of this data is highly variable and does not necessarily provide a level of granularity that allows future refinement – for example, the total volume of concrete can be recorded, but where it was used on the project is not. Clearly, for us to leverage the power of this information, we need to ensure that it is sufficiently detailed to allow improvement, without placing an excessive administrative burden on contractors. We also need to ensure that the way the embodied carbon of any concrete is calculated is consistent, to allow for fair comparisons on a project and industry level.
To overcome this challenge, a ConcreteZero working group is developing a Concrete Measuring and Reporting tool that will allow specifiers and contractors to record and share their concrete information in a consistent format. Providing data through this tool will provide a huge insight into concrete use and carbon intensity and allow a more rigorous interrogation of where we can make savings. It is also anticipated that by systematically measuring and recording embodied carbon there will be a natural response to seek out opportunities to reduce it. This dividend will start to reap carbon savings immediately and will put us in a good position as we strive for further savings.
The need to rapidly reduce embodied carbon is increasingly a key consideration for developers and construction professionals. With concrete accounting for approximately 25 per cent of the UK construction carbon footprint, there is clearly much work to do. The data produced through ConcreteZero will provide the lens to focus our understanding of how we can make savings and will be a vital endeavour if we are to lessen the built environment’s carbon footprint and ultimately reach net zero by 2050.