Leading businesses from different disciplines within the built environment have worked together on an industry-first digital twinning project that will challenge existing design, procurement and construction practices to deliver low carbon buildings and help address the climate emergency.

The landmark study, known as Circular Twin, involved digitally building a school that has already been completed and reworking the scheme from start to finish so that each decision and design choice favoured a lower carbon outcome.

Through this process, the project radically experimented with new working methods, notably adapting who was involved in design work and when, to form an early alliance of experts, with a shared goal to reduce the building’s Whole Life Carbon.

Circular Twin began in response to the climate emergency, now declared by over 300 councils across the UK. The project is possibly the first in the construction industry to put into practice the strategies of the Construction Playbook and guidance from the UKGBC. It proves how the ultra-early alliance of designers, clients, contractor, and the supply chain leads to significant reduction in Whole Life Carbon for modest capital cost uplift.

The project team was brought together by Morgan Sindall Construction as a top tier contractor with design and build responsibilities, along with procurement specialist SCAPE, architects HLM and Lungfish and the multi-disciplinary engineering consultancy Cundall. They discarded conventional industry approaches and collaborated, pooling their extensive experience in both education, construction and sustainable design.

SCAPE, acting as the client, challenged the team to find a better way of delivering projects that achieve the outcomes needed to create a net zero built environment.

In response, they facilitated decisions that were made by the client based on the modelled lifecycle carbon of the building, not cost. Capital and operation costs were evaluated and forecast, but carbon was the key driver. This allowed the traditional paradigms of value defined by cost to be challenged and invited the assembly of the project team, and their behaviours, to change – ultimately helping to achieve long-term cost savings through operational efficiency.

In comparison to the original school – built in 2017 – Circular Twin achieved:

  • 67% reduction in Whole Life Carbon
  • 72% reduction in upfront embodied carbon (EC) (48% reduction in lifecycle EC – this achieves the RIBA 2030 and LETI 2030 Embodied Carbon targets)
  • 52% reduction in annual energy consumption
  • 39% reduction in forest consumption (for products and 30-year UK offset)
  • CAPEX delivered within standard budgetary parameters with multiple over asset lifetime

The project broke the procurement conventions that shackle carbon-reduction innovation, to reap huge benefits. Its key findings highlight how procurement affects the design decision making process and showcases the value that could be captured through vitally important collaboration with the supply chain.

Circular Twin is an industry first, producing hard data, accessible costs and a credible template for a new approach to the built environment.

Louise Townsend, director of social value and sustainability at Morgan Sindall Construction, said: “This initiative has uncovered a revelation – that low carbon construction is inhibited by our industry’s reliance on traditional design and procurement approaches. The outcomes show that achieving low carbon buildings IS possible today.

“Our proposition is that by engaging with contractors at the design stage, we can work with customers to design significantly lower carbon buildings, whilst also working within their budget parameters. Of course, there will be trade-offs and the ultimate cost depends on how far the client wants to go in terms of reducing carbon.

“Ultimately, Circular Twin represents hard evidence of what can be achieved and is a much needed industry-led response to all the urgent challenges we face that will be highlighted at COP26 and have already been made explicit by the climate emergencies declared by local authorities around the country.”

By applying lessons learned from past projects, challenging existing assumptions and utilising unrivalled input from supply chain, the Circular Twin findings have the potential to radically alter how the construction industry achieves its low carbon targets and empowers prospective education clients, local authorities, and other sector-specific clients to achieve their sustainability goals.

Chris Clarke, director of performance and improvement at SCAPE said: “SCAPE advocates that construction clients adopt the environmental standards which have been identified to respond to the climate emergency, which mirror those applied in the Circular Twin project.

“Any part of a project team basing decisions on cost alone is inhibiting low carbon construction. We need to find a better way forward, and ensure carbon is considered an integral part of our decision making hierarchy.

“At the outset of this study we asked ourselves: ‘What would happen if we re-thought the procurement and design process, putting carbon before CAPEX?’ What we discovered is that in re-thinking the end to end process we can balance both without notable compromise.”

Alex Carter, partner at Cundall commented: “The education sector is leading the way when it comes to low carbon design and Circular Twin addresses many of the key challenges we see when designing sustainable schools.

“We’re working together as an industry to create low carbon design solutions and therefore greener, more sustainable learning environments for our children. Working with the supply chain on material selection and collaborating with the wider design team to develop low carbon design options will allow us to make more informed decisions in the future. This not only increases the skills of all involved, but also helps the whole of the building industry to raise its game.”

Yasmin Nally, associate architect at Lungfish Architects said: “The project has allowed Lungfish to work alongside a team of likeminded individuals from different disciplines, giving everyone a place to discuss, deliberate and challenge what low carbon truly means, and how to get to a result which meets the ambitious targets set out.

Philip Watson, director, head of design at HLM Architects said: “Circular Twin has evoked and demonstrated that a sustainable school with carbon at the centre of the decision making is completely possible without special measures, provided a collaborative team and environment is established early.”

“The Circular Twin initiative has uncovered what has been hidden in plain sight by traditional procurement approaches. Namely, that earlier collaboration between client, design team, contractor and supply chain in the procurement process can make low carbon construction and operation possible for very minimal cost uplift.“

Embodying the philosophy of Less Net, More Zero it meets or exceeds industry-leading standards and methodologies such as the Construction Playbook, the UKGBC Net Zero Buildings Framework Definitions, and the RIBA and LETI Guides, as well as SCAPE’s own Recommended Project Environmental Standards.

Circular Twin drew on contributions and guidance from over 250 supply chain partners, enabling the generation of a comprehensive future forecast for the 60+ years life expectancy of the asset in the form of a Lifecycle Cost Model. This helps to create a compelling business case for public sector clients to offset even modest capital cost uplifts.

In practice, this will involve significant upskilling of the workforce through behavioural changes, which will enable embodied carbon to be removed through careful design. Ultimately, this creates operational energy savings, after which, renewable solutions, and finally offsets, can be considered.

To find out more about Circular Twin, please head to YouTube to watch animations that bring the project to life.