As I clear my office after nearly a quarter of century at the SCI, the volume of accumulated material on sustainability is, somewhat ironically, quite staggering.
It also reveals how sustainability issues have waxed and waned over 25 years as the economy has fluctuated and governments and priorities have changed. Despite all the effort, demonstrable progress in many areas of construction is unfortunately not very apparent.
Sustainability or sustainable construction has always been a large, complex and difficult concept to pin down and measure; providing scope for building designers and product manufactures to cherry pick and market their own sustainability claims, aka greenwash.
More recently the urgency of climate change has come to dominate the sustainable construction agenda and for many, the terms are synonymous. From my perspective, while understandable, this is unfortunate and not helpful.
While for some building types, reducing the carbon impacts of buildings through product substitution maybe relatively easy, the reality is that low embodied carbon solutions, are often unsustainable in a wider context. Biogenic construction products may offer carbon benefits however substituting all traditional construction materials like concrete, masonry and steel, is not practically achievable technically or logistically; there simply isn't sufficient land available. Of course, there are also other engineering concerns and challenges with such products in certain applications.
While all efforts to reduce the carbon impact of buildings are to be applauded, low carbon decisions have to be made in a global context and with an understanding of global supply chains; after all climate change is a global issue. Specifying and importing 100% recycled content steel might delight your client on your current project but unless global steel demand is reduced, then net global impacts are unchanged or may even be higher because of additional transport.
Similarly, 'off-shoring' steel production might reduce the UK's national carbon footprint but the global impact will be the same or greater; not to mention the economic benefits and security (of supply) benefits of retaining a domestic steel industry.
Building designers should focus on demand-side material and carbon reductions. Examples relating to steel construction include more efficient and less conservative design, use of higher strength steels, design for deconstruction and reusing structural steelwork; in other words using materials appropriately and as efficiently as possible. Operational carbon savings should also be prioritised. For most commercial buildings operational carbon savings still offer the greatest and easiest reduction opportunities.
SEGRO warehouse and office building deconstructed and relocated on the Slough Trading estate in 2015
This doesn't mean that things don't need to change in the steel sector. Steel is energy and carbon intensive in production and steel-makers need to decarbonise in line with national and international carbon reduction targets. The decarbonisation roadmap for UK structural steelwork was published in November 2021 and the major steel producers supplying the UK construction market have also published their own decarbonisation commitments.
Although the priority for many is minimising greenhouse gas emissions today, the longer term resource and circular economy attributes of products and systems will come to the fore particularly as we transition to net zero. Although we can decarbonise most aspects of society, the resources we need are finite and therefore must be conserved.
During my early time at SCI we were leaders in sustainable construction; arguably a bit too early in some instances. I undertook my first whole life embodied carbon study in 1999 and we first explored reusing structural steel in 2000; both studies that would be timely today. Our first sector sustainability strategy was published in 2002. In Europe we have partnered with leading research organisations on many sustainability projects including those addressing thermal mass, renovation, energy efficiency and thermal bridging and structural steel reuse.
Unfortunately, public funding for construction research has declined sharply over the last 20 years meaning that this early momentum wasn't sustained. More recently, Brexit has meant that we cannot continue to work on EU research projects.
This hasn't just impacted SCI, historically public money was available to fund important pan-industry initiatives including BREEAM, The Green guide to specification, BES 6001, Zero carbon homes and changes to Part L of the Building Regulations. This is no longer the case and important sustainability initiatives are left to volunteer organisations and individuals, with little or no funding. There are also fewer civil servants with knowledge of sustainable construction to facilitate dialogue between government and the construction industry.
Steel construction and steel-framed buildings have many positive sustainable attributes. In the short to medium term, technologies like CCUS and hydrogen will decarbonise steelmaking, deconstruction and reuse will become commonplace and in time, global scrap supply will mean that primary steelmaking is no longer required. At this point steel construction will be carbon-neutral, fully circular and truly sustainable; a vision I remain committed to delivering.
Dr Michael Sansom
Associate Director
