Cutting embodied carbon is not going to be easy. It requires in-depth knowledge of often complex supply chains, a willingness to consider new materials and technologies and the ability to weigh up sometimes competing demands says Soben Head of Sustainability, Dr Bonahis Oko.
From a contractor’s perspective, taking on a contract that demands making savings in embodied carbon can simply look like taking on more risk. Lower carbon materials are likely to have a shorter performance track record than traditional ones, they may be hard to get hold of and they may be more costly or difficult to price.
Traditional forms of contract tend to push as much risk as possible onto the main contractor, who in turn pushes it down the line into the supply chain . In his recent blog, my colleague Derek McFarlane called for a move to contractual relationships that allowed for more equitable sharing of risk, such as collaborative forms of contract like NEC4. Collaboration will be vital if we are to develop solutions that come at a lower embodied carbon cost.
Although collaborative contractual practices do require leadership from clients, we are already seeing proactive contractors taking a lead with their supply chains relationships. Some contractors are already taking responsibility for the carbon footprints of their supply chains and working to understand exactly how and where materials and components are sourced.
The biggest possibilities for reducing embodied carbon, at the lowest cost, comes at the very beginning of a project when basic design decisions are being made: retain existing building structure or demolish and start again; concrete, steel or engineered timber frame? With early involvement of the supply chain, including specialist contractors and carbon managers, decisions can be better informed. Designers could look at issues such as whether lower carbon concrete would be viable, whether engineered timber would be insurable, and what buildability, capital cost and programme issues might arise.
Once projects are underway, there may be opportunities to further reduce embodied carbon. Lower carbon technology and materials are developing fast and, particularly for major or complex projects with a long gestation time, solutions may be available when construction starts that weren’t around at the start of the design phase. But to make the most of such developments, contracts must allow change. It should also be noted that the further along a project is, the more difficult and expensive it is to make changes.
In traditional forms of contract, changes tend to be allowed for via variations or claims. But getting these in place can be time consuming, sometimes inflexible and can also lead to conflict. More collaborative ways of working can allow decisions about change to be made more collectively, considering the carbon impacts and the value they will add to the project within pain and gain sharing arrangements.
Change may also be necessary due to ongoing disruptions in supply chains. For instance, the past 12 months has seen projects which had specified lower carbon steel forced to switch to standard steel, due to shortages caused by the conflict in Ukraine.
Projects that are looking to push further in reducing embodied carbon may also run a higher risk of failures. Collaborative contracts and relationships are better placed to be able to move on from such setbacks, rather than get mired in disputes and apportioning blame.
Developers and owners are already demanding that contractors and their supply chains calculate – and reduce – embodied carbon. In the UK, Landsec is building The Forge, the UK’s first net zero office building in construction and operation, in London. Near Stockholm in Sweden, Nordic Real Estate Partners is building a 215,000 sq ft logistics centre that will be carbon neutral, with on-site renewable energy to cancel out embodied carbon produced due to the construction process. And Norway’s road authority Staten Vegvesen already downgrades tenders with higher carbon footprints than the lowest carbon bidder.
Those contractors who are already working with their supply chain partners to understand embodied carbon and to develop new solutions are on the front foot when it comes to bidding for projects like those mentioned above. And it’s only a matter of time before the measurement and reduction of embodied carbon becomes an everyday requirement.
For a deeper dive into the key considerations for reducing carbon emissions in the construction industry click here.
About Soben Carbon Cost Management
Soben’s Carbon Cost Management service is designed to help organisations achieve net zero carbon affordably and sustainably. We combine industry-leading carbon insights with experienced cost management to go beyond carbon accounting and provide practical carbon cost management advice. With a greater level of granularity than the basic carbon calculators on the market, Soben provides precise and transparent embodied carbon calculations. Our accurate baselines and actionable strategies will reduce your carbon footprint, demonstrating the impact of carbon savings.