Reducing the carbon footprint created by the construction and operation of buildings, which is responsible for almost 40% of the world’s CO2 emissions, is imperative if the sector is to deliver on Net Zero targets. Discussed within the context of the Cities, Regions and the Built Environment day at COP26 climate change conference, to make significant progress in the built environment sector, regulatory interventions and incentives will be required at a national level, together with innovation in materials development and technologies at a global level.

In the UK, the Green Building Council launched its Net Zero Whole Life Carbon Roadmap for the Built Environment, setting out proposed actions and milestones for achieving Net Zero carbon in the built environment sector by 2050, looking at all stages of the project lifecycle. The Roadmap focusses both on reducing operational carbon (emissions created by day-to-day use of a building), and embodied carbon (emissions created in the manufacture, delivery, installation and disposal of building materials).

As part of COP26, the Roadmap was launched at the Blue Zone event called UK Green Building Council Launch of Whole Life Carbon Roadmap for the Built Environment. The speakers pointed out that much has already been done to reduce operational carbon emissions, and whilst there is progress still to be made to reduce operational carbon, addressing embodied carbon will be much harder. A sea change in policies and regulation will be required to achieve the objectives and ambitions of this Roadmap.

Significant, targeted measures – especially for embodied carbon – are needed to incentivise change. The inevitable cost increase involved in product development and sourcing low-carbon materials cannot be borne by any one stakeholder or part of the supply chain. The government may therefore consider fiscal incentives for low-carbon new buildings in order to assist the industry in making the progress required if Net Zero is to be achieved.

Other non-policy levers to lower buildings’ carbon footprints could include:

• increasing the use of Building Information Modelling (BIM) to design energy efficiency into buildings and track what materials are used so they can be reused/replaced efficiently;
• deploying contractual mechanisms to deliver agreed green requirements, e.g. a ‘pain/gain’ element to reward the achievement of certain outcomes or penalise failure to do so; and
• an increase in the use of offsite manufacturing (OSM) as a means of reducing waste, controlling material/energy use, and tracking materials across the whole project lifecycle.

Much of this progress relies on making more use of technology and data to align the industry’s drive for digitisation with the inevitable push towards sustainability. However, the globalised nature of today’s supply chains poses a significant challenge to addressing the issue of reducing embodied carbon.

The industry is already taking innovative steps to optimise how buildings are designed, built, used and refurbished, which is to be commended. It is however acknowledged that the existing policy framework will not be sufficient for the sector to achieve Net Zero targets, and government intervention and incentivisation is required to achieve the transformational shift necessary, particularly in respect of embodied carbon. The new Roadmap is a welcome call to arms; it gives the built environment sector a clear vision for the future and a framework for the government to move from careful deliberation to concrete action.