If you’re taking afternoon tea in the Foyer at Claridge’s Hotel in Central London, you can be forgiven for looking out for celebrities. Everyone from the Rolling Stones to the Queen Mother has visited this iconic establishment – to name just a few in a long line of famous patrons.
Since the foundation of Claridge’s in 1858 dignitaries from Queen Victoria and Price Albert to Winston Churchill and Jackie Onassis have called by. Legend has it that during World War Two, one room was even dedicated Yugoslav territory – to allow a royal resident, the Queen of Yugoslavia, to give birth to the country’s Crown Prince on “home soil.”
But if you were visiting Claridge’s in 2017, you would have had no idea that the most exciting sight in the hotel was far below your ornate table. In an incredible feat of engineering, McGee undertook a project to create a new five-storey basement beneath the Victorian structure – all while the hotel remained fully open to some very refined guests.
As cities grow, they create increasing pressure to expand and renovate historical structures. As the project at Claridge’s shows, completing work in a living, breathing city can cause fascinating challenges and very inventive solutions.
The popularity of Claridge’s has led the owners to expand many times over the years, ever since the building opened as a single boarding house for guests on a terraced street. As the business took off, the family took the courageous step of purchasing all five neighbouring houses in 1854 – knocking through and renaming the hotel Claridge’s two years later.
At the very end of the nineteenth century, a rebuild was necessary. The old structure was demolished and replaced by the impressive Grade II listed hotel that still stands today. But when even more room was needed in 2015, there was no option to build either side – so the owners instead looked below the street to the ground underneath.
Claridge’s put out a tender for the creation of a five-storey basement. The experience of guests, however, remained paramount. As a result, the renovations had to be completed while the hotel remained open, and the guests had to remain unaware of the building work.
35,000 Cubic Meters of Soil, Without Interrupting Tea
The challenge was so fascinating that engineer Jim Mackay opted to come out of retirement to take it on. To keep the hotel open, his engineers landed on the solution of cutting a two-meter aperture in just one room, in Claridge’s art deco wing.
A mining team then tunnelled through this opening down beneath a heavily reinforced concrete raft foundation, which offered the useful benefit of shielding the guests upstairs from the noise. The mining team worked, often for 24 hours a day, to remove 35,000 cubic meters of soil through the opening – and feed in over 20,000 cubic meters of concrete and building materials.
Thanks to their incredible logistical planning, the team completed the £35 million project in January 2019, creating five new storeys and an estimated £120 million of real estate for Claridge’s, all while the guests enjoyed their fine dining uninterrupted. As Mackay noted, “It was a career-ending job – but also, maybe, a career defining one.”
New Space in Ancient Cities
The Claridge’s Hotel project reflects wider challenges in finding new space in cities, like London, with an extensive historical heritage. Every day, 200,000 people worldwide move from rural locations into cities – and by 2050, it’s predicted that two in three of us will live in urban areas.
There’s massive demand for more housing, business space and facilities. However, in historical cities especially, this can’t just come from new buildings, but expanding and renovating existing structures.
But this is no simple task in long-standing cities. In London, for example, projects might contend with historical street layouts, laws protecting sightlines (such as around St Paul’s Cathedral) and underground infrastructure like tube and trainlines – themselves dating back hundreds of years.
Projects need to remain sympathetic to the existing architecture of the building and surrounding areas. And of course, just as in the case of Claridge’s Hotel, cities need to remain functional for their many workers, residents and visitors, so construction has to cause as little disruption as possible.
3 Technologies Linking Past and Future
Engineering and construction firms will need to draw on the very latest methodologies and technologies to make the best use of the space in our cities:
- 3D building information modelling: For complex renovation and expansion projects, being able to visualise work in 3D can be critical to completing it accurately and on schedule. Today, BIM tools are available to access 2D and 3D models on-site, to support the team while they work.
- Off-site manufacturing and 3D printing: OSM offers a way to create tailor-made structures and components away from the site itself, which can offer significant advantages for complex or busy historical builds. Accurate digital drawings are vital, though, to ensure that the components meet specifications and can be installed accurately.
- As-built digital records: One of the major challenges of expanding historical buildings is a lack of accurate paper records on both original layouts and the many renovations over the centuries. Now, owners can benefit from accurate digital records at the end of projects, to support buildings’ maintenance and further expansion in the future.
Challenging projects like Claridge’s Hotel are likely to become more common, as rapid urban expansion makes it more vital to make the best use of existing buildings. But with innovative methods – and the latest digital technologies – we can build new life into historical cities and ensure they meet our needs for centuries to come.
Read more about how construction technology is preserving historical sites like Notre-Dame.