Retrofitting listed London office buildings presents more of an opportunity than a challenge

The journey to net zero is more important than ever, with the UK recently doubling down on its pledge to reach net zero emissions by 2050. Those working in the built environment have a key role to play, and retrofitting is crucial if we are to reduce carbon emissions and protect and sustain the architectural fabric of our cities.

As custodians of Grade I and II listed buildings across prime central London, the Argyll team realises the importance of protecting the history embedded in the walls and streets of the city we occupy. Our recent capex refurbishment programme presented an opportunity to bring the Argyll portfolio up to speed with the demands of the modern workforce while celebrating the architectural history of the buildings and playing our role in the city’s sustainability efforts.

Working with heritage consultants and leading architect Damion Burrows (DMBA) we were able to strategically update seven of our buildings in line with the sustainability demands of the 21^st century. Key to our programme was the ability to see retrofit not as a barrier or obstacle but as an opportunity to preserve the heritage of our office buildings while aligning them with a more sustainable future.

Of course, delivering effective retrofit strategies – particularly when it comes to listed buildings – is not without its challenges. From Argyll’s experience retrofitting its portfolio, and through conversations with heritage consultants and sustainability engineers, it is clear that there are inconsistencies in planning and approval processes. However, the recent unveiling of the retrofit toolkit for heritage buildings of the Square Mile from the City of London Corporation marks a clear step in the right direction for a ‘retrofit first’ approach.

One challenge our retrofit programme has had to tackle is the refurbishment of our Grade II listed building, 1 Cornhill (pictured), at the heart of the Square Mile, opposite the Bank of England. From replacing the heating and cooling system, reducing energy consumption through motion-sensor lighting and designing a heritage lounge that sensitively restored the building’s original grandeur, the retrofit had to navigate complex and inconsistent planning regulations and conservation challenges. Following refurbishment, the building achieved a B EPC rating, having previously been rated a D.

Our site at Central Court, Holborn, is another perfect illustration of the responsibility that comes with retrofitting sympathetically. Formerly the London Patent Office, where household name brands like Lego first got the seal of approval, it is now a state-of-the-art workplace. We have worked with the rich historic fabric of the building to make the most of the high ceilings, sash windows and intricate existing architectural features and while there were challenges, we have greatly improved energy efficiency with a minimum intervention approach.

More government support is needed to unlock the potential economic output generated by retrofit, which was recently estimated at £35bn annually. We hope the new government will recognise the importance of incentivising retrofitting. If only new builds continue to receive VAT exemptions, a demolition-and-rebuild mindset will remain. Financial incentives for retrofitting are urgently needed if we are to bring our existing stock in line with carbon targets.

It is also vital that government introduces a policy to bridge the heritage skills gap currently holding back the sector. If we don’t quickly upskill our engineering and construction industries with retrofit in mind, guidelines like the Retrofit Toolkit will be little help when it comes to sourcing the labour and skills required to secure the future of our heritage buildings.

Heritage buildings at first glance may appear to present a daunting hurdle to net zero goals. However, given 80% of buildings that will be occupied in 2050 already exist, decarbonising existing stock is crucial. A retrofit-first approach requires perseverance but it is feasible and absolutely essential to securing the future of London offices.