Going the extra mile in learning how to produce sustainable buildings
It shouldn’t come as a complete surprise but generally around 40% of the UK’s carbon emissions can be linked to the built environment. The construction sector is also responsible for around 60% of total UK waste. These facts are part of our inspiration and drive to help the industry become more sustainable.
When considering the future and our transition to Net Zero by 2050, until now, when it comes to the built environment, most of the attention has been paid to quantifying and reducing the operational carbon emissions over the lifespan of a building. This work has focused on aspects such as heating, lighting and operating appliances, as its easier to understand why they contribute to operational carbon. And luckily, as we move towards renewable energy sources and improve the energy efficiency of our appliances, operational carbon emissions are forecast to significantly reduce.
However, reducing the overall carbon emissions of our buildings is a two-pronged approach.
The second aspect focuses on construction, maintenance, and deconstruction, and mostly involves the embodied carbon in the building materials we use. Embodied carbon is essentially the total of all the emissions which a certain amount of material produces, and in turn contributes to climate change, over its entire lifecycle. Only recently has the construction industry been able to precisely quantify the embodied carbon – the total carbon released in manufacturing, transporting, constructing and eventually deconstructing each individual building material, or element.
Simply put, the higher the carbon intensity factor a material has by weight, the worse for the environment it is. Yet, some materials – generally concrete – which have lower carbon intensity factors get used in such significant quantities, that their overall contribution to the total embodied carbon of a project is significant. Putting it into context, something widely reported, is that if the cement industry were a country, it would be the third largest emitter of CO2 in the world.
It is predicted that in the not-so-distant future those who design the built environment will be mandated into measuring the embodied carbon of the materials in their buildings. Ultimately, there are likely to be limits placed on the upfront embodied carbon in the structure, with upfront meaning that it is measured up to the point of handing over the final built asset.
So, to pre-empt the drastic changes the industry faces, the team here at Superstructures is committing to drive innovation around sustainability and decarbonisation. We want to do the right thing, not just do things right, and above all else, we want to ensure that when regulations are imposed, we are prepared for the dramatic changes the industry faces.
I am part of the sustainability team at Superstructures with my colleagues, Charlie Dando and Holly Peirson. We are encouraged to work together, to not only learn more about how to produce greener buildings, but to create a strategy that focuses on what our company should do, and how this can be implemented.
Fundamentally, as well as reviewing methods and process, and the materials specified, we are looking at how we can work collaboratively with our clients, ideally earlier on in a project’s overall development, so we can have more impact in the design process. A good first step is to reflect on past projects, revisiting original ‘business as usual’ designs to quantify the impact of using more sustainable design approaches.
For instance, we looked at The Cart Lodge, a steel and concrete building covering 67 square metres which was designed in 2021. Revising the design of this small building helped reduce the embodied carbon emissions of the structural elements by around three tonnes. In itself, this doesn’t mean much, so to bring context to the savings made, we compared it to how many years of cycling to work it would take me to offset the first design against the second. The answer was an astounding seven years! Open the accompanying pdf to delve deeper into the numbers. What’s interesting is that if we can make these savings on a comparatively small project, how significant would they be for a larger scale building, such as a school, or a commercial retail outlet?
Why aren’t we already doing this?
The answer to this isn’t straightforward and involves many different factors, some of which include: industry norms, lack of established standards, limited architectural influence to enable sustainable materials to be used, a lack of client demand and an educational gap.
Overall, cost is probably the most prohibitive factor when it comes to implementing sustainability. Currently, to apply sustainable building practices, upfront consultancy fees are higher, but the result is that by seeking professional input earlier, your design will be better optimised to efficiently use specified materials.
An example of this is using a timber load-bearing frame, as opposed to using heavier masonry. Doing so means that the building is lighter, meaning less structural materials are required to simply hold itself up, which in turn creates less load from their own weight. Ultimately there is a cascading effect; a lighter Superstructure requires a lighter Substructure. Simply put, when one process becomes leaner and more efficient, the next process gets leaner and more efficient and so on.
Here at Superstructures, we are being proactive, choosing not to ignore the issue, but preparing for a future where buildings are totally sustainable as the norm.
Sustainable design philosophies can and should be used in every project; by creating a numerical framework for comparing designs, we are in essence teaching ourselves iteratively on how to make ‘greener buildings’ which align with the UK’s Net Zero ambitions.
The crucial ingredient needed to help us implement these changes is collaboration. To deliver a successful green building, the parties involved cannot work in isolation; they must be united in both their ambition and execution of sustainable building strategies.
We are continually developing important skills in our team so that all of us can produce and talk competently about more sustainable structural designs. Importantly, we are not complacent, and we all acknowledge our personal and professional responsibility to push harder towards a more sustainable future together.
By Michael Kaye, Graduate Structural Engineer, Superstructures
