Working towards a more sustainable construction sector

11 February 2022

Last year, COP 26 drew all eyes on the UK as world leaders and sustainability experts came together to plot out a renewed strategy for a greener future.

Construction, which is a substantial net contributor to current global emission levels will rightly be in the spotlight, and in the aftermath of the event, there will no doubt be an expectation that everyone from specifiers and asset owners to building product manufacturers and ConTech providers will double-down efforts to achieve Net Zero by 2050.

Taking a top-level perspective, we urgently need to adopt a more circular and imaginative approach towards the built environment, from the smallest dwelling to the largest piece of critical infrastructure.

So, when construction sector boards gather over the coming months, to review their ESG strategies post-COP26, I hope they take a holistic view as they plot a more eco-friendly path for their businesses to follow. Fundamentally, we need to use less stuff. Then we need to use the right stuff (low carbon). And then to get over the line we need to offset, if necessary. We literally have all the building blocks in front of us already – we need to (re)use them.

First and foremost, we need to drastically reduce the excavation of virgin raw materials and the manufacturing of high carbon ones. Although the manufacturers have their role to play in driving down emissions, specifiers and contractors can play a key role too. It would be great to see them champion better use of the materials which are currently held within the existing built environment, investing more in exploring emerging concepts such as ‘urban mining’ as well as traditional ones like smaller supply chains.

We also need to review many of our existing built assets, looking at where we can give older, perfectly acceptable structures a second life, whether residential or commercial. We need to make demolition a last resort rather than a primary course of action. Through this we can lower the amount of fuel, energy and human power on-site and drive maximum value in ready-built, structurally sound stock by increasing its lifespan.

Amazing initiatives, such as the Iceni project are demonstrating how adapting existing, derelict stock can help to drive growth and regeneration, especially in urban areas, highlighting the socio-economic benefits of repurposing.

Adopting a broader, more ecologically intuitive approach to design and construction is all part of this. Thinking of ways to deliver more with less to bring maximum comfort with maximum sustainability, should now be a priority for any engineer or architect to then cascade down through the construction journey, encompassing the whole building life and beyond. I should add that this includes looking at where technology can be incorporated to reduce waste and investing in appropriate solutions where relevant.

Equally as important, we need to establish a much more rigorous and discerning approach to conversations with clients. We need the ability to re-imagine the brief such that the outcomes are met, but possibly through building far less, if anything at all. We need a business model to drive the ‘minimal intervention’ intellectual contribution which engineers and architects can (and must) make to reduce our reliance on project cost.

However, there are plenty of small gains which could be made before we have to start looking at overhauling business models. Our design load assumptions offer huge scope for being revisited to slim down our structures. How many designers ever picture what 5kN/m2 actually means in terms of loading in an assembly area, for instance? Not only will rationalization of loading, coupled with rationalization of serviceability requirements, reduce waste, but also deliver better margins and efficiencies in the construction journey.

Going forward, construction without purpose or value will push us further towards an ecological point of no return. If we go beyond it, we’ll be irreversibly damaging our planet and society simultaneously. So the sector needs to adopt a more intuitive and responsible approach to future projects. The question that should always be asked is ‘Is it necessary?’

Technology definitely has a role to play in this, and we have a plethora of advanced digital tools and systems which are proactively helping with this journey, including parametric design tools, carbon accounting indicators and real-time capable BIM Modelling software. We could use traffic lights in spaces in buildings, akin to lift and airplane loading limit alarms. And we could use white noise to dampen vibrations, or actuators to dampen sway.

It’s all there, ready to use. However, the issue now is less about technology and more about know-how.

Technology will play its part in reducing waste through delivering greater precision, automating processes and managing consumption. However, as was the case in the journey towards greater digital adoption, we need attitudes to change more urgently.

Hopefully, the next fortnight’s events will encourage greater reflection on the sustainability topics, encouraging the sector to make a renewed, and firm commitment to mitigating and reversing climate change.

Prof. Tim Ibell, Dean of Engineering & Design, University of Bath

Tim joined the Department of Architecture & Civil Engineering at the University of Bath in 1997. In 2002, Tim spent a year in the United States on a Fulbright Distinguished Scholar Award. He was promoted to Professor in 2003 and held the role of Head of Department from 2005 to 2008, and again from 2010 to 2013. Tim was Associate Dean (Graduate Studies) from 2008 to 2013 followed by Associate Dean (Research) from 2013 to 2017. After a year at Cambridge as the Sir Kirby Laing Professor of Civil Engineering, he returned to Bath in 2018.

Tim was President of the Institution of Structural Engineers in 2015, and he is a Fellow of the Royal Academy of Engineering. He and his team have received six best journal-paper awards, including three each from the Institution of Structural Engineers and Institution of Civil Engineers