By Jarrad Warhurst
Why Circular, Why Now?
The world is at a precipice. We’re living through a climate emergency, with global ecological systems approaching or past dangerous tipping points. Through the sheer scale of its demand on energy and resources, construction has a significant impact on climate and ecological systems, contributing to biodiversity loss, habitat destruction, unsustainable resource consumption and carbon emissions. But there’s momentum for change.
At a time when our resources are finite and our population is growing, the circular economy offers a different path forward. At its core, it’s about transitioning to a closed-loop system where resources are reused rather than continually extracted and discarded. In a circular model, we minimise waste and design for long-term adaptability. We reuse materials from demolition sites, repurpose structural components and build in ways that give the built environment the ability to regenerate rather than deplete.
At a technological level, many of the solutions already exist. We know how to produce steel with a low carbon footprint. We’ve developed safe, practical ways to use timber in commercial buildings, overcoming previous limitations around fire safety. New technologies are emerging all the time, and innovation in materials and construction methods is moving quickly. But barriers still persist.
The ultimate goal? For the built environment to give back more than it takes, to reach a point where buildings actively support biodiversity and improve the ecological conditions around them. Is that achievable? Maybe. The process is complex, but we need ambitious goals to strive for. Even when we fall short, we’re making positive progress.
Economic Pressures and the Business Case
In principle, clients want to be sustainable. But the reality is that construction is under a lot of pressure. Since the COVID-19 pandemic, we’ve seen labour shortages and rapid cost inflation in materials, and many contractors are struggling just to stay profitable. In some cases, major construction firms have gone under.
So, it becomes a question of prioritisation. How do we balance immediate business pressure with what’s important for the planet?
Clients answer to many different stakeholders: shareholders expecting a return, tenants who occupy the space, lenders, supply chain partners and government regulators. Sustainability becomes a much easier sell when those stakeholders are all aligned. We’ve got to make sure it’s not left to the developer, the architect, the engineer, or any single stakeholder to decide on sustainability. Renters need to be clear about what they expect from a building’s sustainability credentials, and shareholders also need to be pushing for change from their side. If we are to effectively tackle the climate emergency, we need a unified, collective approach.
Government policy plays a big role too. With the right incentives and a strong commitment to green infrastructure, governments can tip the economics in favour of circular solutions. That could mean shifting subsidies away from fossil fuels and towards renewable energy, or investing in circular economy sectors to support job creation.
We need to make sustainable choices the most straightforward option. When circular solutions are also the most cost-effective and commercially sensible, clients will embrace them without hesitation.
Embedding Circular Thinking in Design
At Robert Bird Group, circular thinking is at the heart of what we do. There are a few key principles we try to apply across every project:
Use less stuff
If a component isn’t needed, we try not to build it. That might mean eliminating a basement level or reducing a building’s height if those upper floors aren’t adding real value. We aim to make the materials we do use work as hard as possible.
Design holistically
We look at the full lifecycle of the project, not just the finished building. That includes enabling works, groundworks, basements, the frame, temporary works and more. Sometimes a so-called “green” material can extend the programme or require lots of temporary works, which adds extra lifecycle carbon and cost. We always aim for the best overall sustainability outcome.
Prioritise longevity and flexibility
Some of the world’s most beautiful buildings have stood the test of time. Instead of the standard 60-year design life, can we make it 120 years? And can we design for flexibility so the building remains useful over time? It’s disheartening to see buildings constructed 20 years ago already being demolished. It tells me they weren’t adaptable enough – they didn’t meet the needs of the future. Prioritising longevity and flexibility inevitably increases costs. What we need are government incentives that reward circular thinking and balance the short-term financial loss. The industry should not be penalised for doing the right thing.
Plan for end-of-life reuse
Once we’ve optimised and extended the life of a structure, we still think about what happens when that building is eventually decommissioned. Can steel be recovered and reused? Can components be catalogued in a database for future use? At the moment, reclaimed supply doesn’t match demand, but that can change if the industry starts sharing data and planning ahead. Material passports should be mandatory, regulated and standardised.
Material Passports
We need a system that allows materials to be tracked, reused and valued beyond the life of a single project. Processes do exist, but they are not standardised across the industry. Too often, products come to the end of use with no clear route forward, not because they have reached the end of their life, but because no one is prepared to take on the warranty or the risk. That gap in responsibility is one of the main reasons why valuable resources continue to become waste.
Material passports provide the framework to change this. By tracking all of the materials, members and products we put into projects, we can build an ecosystem for circularity that allows materials and products to be reused at scale. A passport acts as a record of how a material has been used, what condition it is in, and how it can be recertified for future projects. With that information in place, buildings stop being seen as a collection of disposable components and start to act as repositories of resources for the future.
Adaptive Reuse: Seventy Gracechurch Street
An ongoing project in London that exemplifies these principles is Seventy Gracechurch Street. Located in the heart of the city, it involves the transformation of an existing eight-storey Marks and Spencer office building, originally built just over 20 years ago. Rather than demolish and start from scratch, we are retaining around 60% of the existing structure. This includes the basement and much of the superstructure, with a new 33-storey tower being constructed above and around it.
This approach allows us to preserve embodied carbon and avoid unnecessary waste. At least 120 tonnes of steel beams are being reclaimed from the original structure, recertified and reused within the new build. Any steel we cannot reuse on site is being sent for recycling.
It’s a fantastic adaptive reuse story and a strong example of how circular design can deliver commercially viable, future-focused outcomes in dense urban settings.
Shifting Mindsets
One of the most encouraging shifts I’ve seen is at the grassroots level. More and more people in the industry, especially younger engineers and designers, are personally motivated to drive sustainability. That individual momentum is really powerful.
On the flip side, I’ve noticed a slowdown at the broader industry level. Sustainability doesn’t feel as urgent or visible as it did two or three years ago. There’s a kind of fatigue that’s set in. After years of constant climate news and economic stress, some people are just tired of hearing about it. That fatigue is dangerous because it can stall progress right when we need to accelerate.
We have to cut through the noise. We know this is the right direction, and we know it’s going to benefit everyone, especially those with fewer resources who are likely to be hit hardest by environmental decline.
Clean Energy is the Future
One innovation that I believe will define the next decade of engineering is the transition to cheap, abundant and clean energy. Energy is the cornerstone of everything we do. If renewable energy becomes cheap and widely available, it has the potential to transform the economics of sustainable construction.
Suddenly, producing green steel or recycled aluminium becomes not just possible but cost-effective. Running buildings becomes cheaper. Recycling materials becomes more viable. Clean energy has the power to trigger a domino effect across the entire supply chain.
The UK has already made big strides with wind power and nuclear, but there’s potential to go even further. Tapping into all our renewable resources, including tidal and hydro, which is massive in this part of the world, could position the UK as a leader in exporting low-carbon construction materials globally.
Cheap energy can enable the industrialisation of low-carbon materials. But it has to be clean. If we chase cheap energy from fossil fuels, we undermine the whole effort.
Collaboration is Key
Collaboration has to become cultural if we are going to deliver circularity at scale. Progress will only come when working together is embedded at every stage of a project and seen as part of the industry’s identity. It cannot be about business interests on one side or sustainability on the other. A holistic approach is needed, where engineers, architects, contractors, clients and supply chains join up their expertise and share responsibility for outcomes.
This means setting up systems that allow information about materials to be shared, warranties to be carried forward, and risks to be placed in the right areas, so that reusing components becomes routine. It also means thinking about how success is defined. If the industry continues to reward individual gains or short-term outputs, progress will be slow. Real change will come when success is measured collectively and when behaviours are shaped by the goal of achieving lasting positive outcomes for society and the environment.
Circular engineering is not something that can be delivered by one discipline or organisation alone. It has to be driven through stronger partnerships, built on a culture of collaboration rather than competition.
The challenges are vast, the barriers significant, and our ambitious targets in response to the environmental emergency may be missed. But I am optimistic. People, industries and organisations can find a route through this time of political and ecological turmoil. We are moving in the right direction, and we need to maintain that momentum.