Why retrofitting is the future of construction

The term ‘retrofit’ is everywhere right now, and it represents a fundamental shift in how we approach the built environment. This move is driven by the urgent need to reduce carbon emissions and achieve Net Zero targets. At Perega, this it is an exciting time as we are very familiar with this type of challenge and we are proud to place engineering innovation at the heart of the UK’s sustainable future.

An engineer’s role in the circular economy

Thinking ‘Retrofit First’ means adopting a circular economy mindset and looking for the value in what already exists. As engineers, our first step is to act as detectives. This means digging into historical archives to find original drawings and designs, conducting detailed structural surveys to map out the existing frame, and often carrying out material testing to verify strengths and qualities of the original concrete or steel. This investigative work uncovers the hidden potential within a building’s structure, allowing us to determine the best ways of adapting and strengthening it, thereby saving vast amounts of embodied carbon that would have been required for new build and ultimately substantially reducing waste. It delivers huge environmental benefits and often results in faster project timelines and significant cost savings for clients.

Innovation in practice

Making an old building fit for the 21st century requires a creative approach. We employ a range of innovative solutions to upgrade structural performance without compromising the building’s character. This might involve introducing lightweight new systems that work in harmony with the old or using advanced materials to selectively strengthen key elements. It’s about finding the smartest, most efficient way to prepare a building for a long and productive future.

Each project presents a unique puzzle and similar solutions can be adapted in different sectors. It could involve strengthening an existing frame to remove internal columns; creating the open-plan layouts that modern tenants demand. It might mean adding new floors using a lightweight timber structure that the original foundations can comfortably support. We can apply advanced composite reinforcements to bolster the strength of existing concrete, yet just as importantly, without adding significant weight. The goal is always the same: a bespoke solution that balances best performance with respect for the original structure, delivering a building that is ready for the future while honouring its unique past.

The tangible benefits: beyond carbon savings

While the environmental argument for retrofitting is compelling, the commercial benefits are just as powerful. By working with an existing structure, project timelines can often be significantly reduced compared to a full demolition and rebuild, meaning a faster return on investment. The cost savings can also be substantial, avoiding the expense of major demolition, extensive groundworks, and procuring an entirely new superstructure.

Furthermore, retrofitting preserves a building’s character and story, creating unique, desirable spaces and can make an existing building stand out in its location and significantly improve local community feel. This authenticity is a powerful commercial asset, attracting tenants and buyers who value distinctiveness and heritage. It’s a strategy that delivers value across the board, for the planet, for the client’s budget, and for the local community. This holistic approach ensures that retrofitting is not just an environmental choice, but a smart, commercial decision that aligns environmental responsibility with sound financial investment and long-term asset value. It’s a win-win scenario.

Designing for the future

Effective retrofitting also means thinking about the next generation. By embedding circular economy principles into our designs now, we can make future adaptations that much easier. Reusing elements of existing buildings by adapting them in different assets is one of the key steps in the hierarchy of net zero. This shift in approach allows for exploring opportunities in design for disassembly and expanding reuse of components at the end of their life.

The journey to Net Zero depends on making the most of our existing assets. By combining a passion for problem-solving with technical expertise, we can transform the buildings we already have into the sustainable, high-performing spaces we need. This is how we will deliver a built environment that is richer, more characterful, more considerate for local communities and truly sustainable for future generations. While safeguarding our architectural heritage and meeting our climate goals, we can build a resilient and prosperous future for us all.

By Monika Rogers, Associate and Net Zero Carbon Lead