How an Oxford college's focus on low carbon materials led to champion status

As of late, energy efficiency has been the name of the game.

It was also the challenge set to the Gradel Quadrangles team when working on a new development for New College, part of the University of Oxford.

The team could've followed existing practice and boasted about the scheme's sustainability.

But associate professor of engineering science, Barbara Rossi, decided they should go further.

Dramatic carbon reductions

Located close to the medieval Oxford City walls, the development will host student accommodation, teaching spaces, and a porter’s lodge for New College.

Professor Rossi worked with Richard Bayfield, project director at New College and sustainability officer at Sir Robert McAlpine.

Together, they made a plan to dramatically reduce the embodied carbon of the project, resulting in carbon savings of more than 650t of CO2e (embodied carbon) from the build.

This, without affecting the energy efficiency of the finished structure.

For their work, Professor Rossi and Bayfield gained ICE Carbon Champion status.

‘Fresh thinking’ reduces carbon

Professor Rossi highlighted that achieving Carbon Champion status is accessible to all. It just requires ‘fresh thinking’ and positive action.

On the Gradel Quadrangles project, the team realised that operational efficiency was close to optimal.

So, to reduce the impact on the environment, they chose to use less carbon-intensive materials and techniques. All while meeting the existing performance criteria.

The Gradel Quadrangles team tried the following:

• By moving to a timber-and-aluminium roof rather than using sprayed-concrete, the team saved more than 200t of CO2e.
• By being selective about types of cement for piling and sub-structures, they cut out a further 380t.
• Use of local stone for cladding shaved off almost another 100t.
• Sustainable staff transport and renewable electricity were other measures incorporated throughout the build.

With half the project left to go, there's huge potential to minimise the carbon footprint of the project.

Professor Rossi also recommends:

• Foundations don't need to be 100% Portland Cement, substitutes are available.
• Use the embodied carbon footprint database to tune material requirements to low-carbon alternatives.
• Avoid over-designing beams and columns for strength or thermal performance.
• Work with suppliers to see what types of materials they can provide. Look for low carbon alternatives.

Seeing the potential

Professor Rossi said she initially doubted they’d get Carbon Champions status for a small project outside of London. She said the team was thrilled to be recognised.

“It backs up what we're trying to do. Everyone on the project is working even more sustainably since receiving the award," she said.

“It also means a lot to me as an early-stage professor, building my team and my lab," she said.

"People contact me asking to know more about the project and my peer-review, so I am increasing my network. Graduates and undergrads want to work with me,” Professor Rossi said.

There are benefits for the wider industry too. And let's not forget, progress towards net zero.

“People who didn’t know the impact of construction on carbon emissions suddenly see the potential,” said Professor Rossi.

Recognise and recreate

The starting point for the Carbon Champions programme was to help the industry take the lead on the UK’s drive to net zero.

There's so much information out there on decarbonising construction. It can be overwhelming.

ICE wanted to provide accessible examples of real-life interventions.

There are two tiers to our approach. First, recognising best practice and sharing it with the world so it can become the industry norm.

Then, we want to share these examples of sustainable innovation in more detail. These could become the norm in the future and they should if we're going to achieve our climate goals!

The future of Carbon Champions

In the end, we hope the Carbon Champions programme will be so successful it becomes redundant.

Why? Because it'd mean that everyone in and around the industry is working at these levels.

Who knows? Someday, achieving the status could be mandatory to become a chartered civil engineer.

How to become a Carbon Champion

The ICE Carbon Champions is a platform to recognise people doing important work.

You don’t have to be working on a hard-hitting flagship project or be one of a handful of senior individuals usually in the public eye.

The only criteria are having specific examples of saving carbon and being able to prove it.

The process

Applicants must identify carbon savings and share their method for calculating them.

The ICE Carbon Champions Review Panel then assesses each entry against a pre-determined scoring matrix. A grading is determined, then the entry is discussed at a regular meeting of industry experts.

Those who meet the standard are officially recognised as ICE Carbon Champions.

Those interventions are seen as having game-changing potential. Thus, they're often shared with the ICE community as case studies and videos.

If more information or work is needed to become a Carbon Champion, ICE will try to pinpoint areas for improvement.