WilkinsonEyre, working with engineers Robert Bird Group, has completed a new headquarters for Deutsche Bank in London – a building that somehow manages to straddle the complex Moorgate Station interchange below.

Words
Jason Sayer
Photos
Dirk Linder & Ben Bisek

As architects go, WilkinsonEyre are remarkably good at doing bridges. The Millenium Bridge in Gateshead, the Bridge of Aspiration at the Royal Ballet School in London, and Lille Langebro in Copenhagen, to name a few, are some of the practice’s best. They’re quite good at buildings, too: Gardens by the Bay in Singapore, Gasholders London and Stratford Market Jubilee Line Depot – the latter being one of the firm’s earliest projects, all spring to mind.

But so far, never the two – buildings and bridges – have met.

At London’s Moorfields, however, that’s changed. The project being referred to here is officially known as Deutsche Bank HQ and, as its name suggests, is the new London head office for the German bank. Now host to 5,000 Deutsche Bank employees, the HQ is a building that incorporates a new bridge to the Barbican and new walkways across the site – all while being suspended across the hellishly complicated Moorgate Tube-Elizabeth Line interchange below.

The project began back in 2012 when WilkinsonEyre was commissioned by Landsec to drastically increase capacity to the site, in response to the new Elizabeth Line station coming at Moorgate. If you’re going to bring many new people, predominantly office workers to the area, having a place of work for them naturally capitalises on this, so the mantra suitably goes.

Some beg to differ on the timeline: Giles Martin, director at WilkinsonEyre argues the project had, in theory, started much before 2012. “We’ve been doing Crossrail for 30 years. Unbelievably, we started it in ‘92 and the CrossRail team had the foresight to suggest finding a way of putting a structure in that would mean you could fit a building on top,” he told AT.

So that, many years later, is what they did. To achieve this, the original buildings (three anonymous blocks from the 1970s not, say the architects, “viable to bring up to contemporary standards through a retrofit approach”) on site were removed, eventually making way for the 16 storey Deutsche Bank office. The next problem, a much bigger one at that, was below ground. As construction of the project was forbidden from interrupting tube service even for a single day – the cost of shutting this section of just the Circle Line just for a single day being north of £1 million – foundational piles had to navigate around and in between the myriad network tunnels.

The initial design solution put forward to Landsec was for two buildings, however, that went out the window when  Deutsche Bank (through Lendlease) came in looking to acquire the site for its headquarters, the only problem being, that it wanted 20 per cent more space.

Adding height to each building was prohibited as this blocked views of St Paul’s so the solution, to help Landsec later secure its deal with Lendlease and Deutsche Bank, was to have one (very) big (and very heavy) building.

During this time, engineers Robert Bird Group had been testing the foundational capacity of piles on the site. From this, they had discovered it was possible to have piles plunge 60 metres into the ground, so far down they reach the fine, pale grey sands of the Thanet Formation – a 58 million-year-old geological phenomenon named after the Isle of Thanet in Essex.

At 2.4 metres across, these piles can take a load of 55 MegaNewtons, the equivalent weight of around 12 full-loaded Boeing 747-8s. The working load on the piles used for the Shard, by comparison, is around 30MegaNewtons (MN).

“Pushing the design to the limit required increased testing and monitoring requirements,” Nick Cole, director of Robert Bird Group told AT. “A 50MN top loaded pile test was carried out on a 1.2m diameter sacrificial pile, using four of the permanent piles as reaction piles. As the reaction piles needed to be constructed in advance of the test, they were designed with a higher safety factor so that they did not rely on the results of the test (in the event of a lower than expected test result). The pile test recorded a pile capacity 25 per cent greater than the failure load predicted using conventional theory of deep piles in London and the 73mm settlement under maximum load was a fraction of the 300mm predicted settlement.”

“The test pile, and all permanent piles, were instrumented with CemOptics optic fibre strain gauges along the full shaft length. This has allowed the team to monitor the strain profile along every pile, with real-time measurement of the load distribution in the foundations. The results of these previously unrecorded measurements have reset conventional understanding of the mechanism for load share between the London soil strata.”

There are now 15 of these piles, aptly dubbed ‘super piles’, with seven of these on the northern part of the site, between the Union Street thoroughfare and tube tracks below. Eight more piles, with seven of these being 1.8 metres in diameter, exist on the southern side of the tube lines, between them and the westbound Elizabeth Line tunnel.

As a result, the building spans across six tube line tracks, but perhaps more impressively, stretches along the entire length of the station, all while managing to avoid Northern City Line trains (that come in from Welwyn Garden City and Stevenage) that terminate at Moorgate, as well as the Northern Line tube trains that run on through.

The building’s structural skeleton shows how loads are carefully managed by coming down onto each of the piles below.

Site plan showing where each of the piles are located.

Back at ground level on the main pedestrian artery – known simply as Moorfields – can be found the new Moorgate Station entrance, also designed by WilkinsonEyre. The area is busy: the Globe Pub opposite attracts enough people, mostly Rab-clad and navy-blue suited folk, that they spill out far into the street even on day that isn’t a Thursday (London’s official day for imbibing). Despite the activity, the northern end of this street can be dark, the building across rising to six stories resulting in quite a shadowy experience, particularly at dusk.

WilkinsonEyre’s work in this context stands out as a welcome bit of illumination. Though the station is the main focus for the majority of people walking through here, either side are entrances to Deutsche Bank – each manned by a security guard, with the southern entrance being accessed via a short escalator. “They wanted curb appeal said Martin. “From Moorgate and from the main thoroughfare down to the Bank of England, you’ll see through and see their logo.”

Above that is an impressive tectonic display of structural prowess. It’s hard to miss – and we’re all the better for seeing it, too. “Every nut and bolt is on show and illuminated,” Martin continued. Like an upside-down root diagram, the building’s truss is expressed in its façade, with this network of metal coming down to rest on two of the super piles below.

“It’s actually asymmetrical, but you wouldn’t see it because you only see it obliquely, you just see a pattern that makes sense. But finding that geometric pattern that made sense was so important because it’s the kind of expression of the engineering of a building, and that’s kind of what it’s all about,” he added. “Trying to find a language to make that engineering work has been my life’s challenge.”

The reason the building’s truss has been expressed in this way is to let the piles below take the weight of the building due to complications in bringing partitions to the façade, and to provide a column-free interior, suiting the needs of Deutsche Bank who wanted four football pitch-sized floors to accommodate 600 traders. Top traders can earn up to £50 million-a-year for companies, making Deutsche Bank’s lease on the site a worthwhile investment. While that deal is undisclosed, the project in 2022 was sold by Landsec to an investment vehicle managed by Lendlease for £809 million in September of that year, a deal that included a 25-year lease for Deutsche Bank on the property. The construction value of the project, meanwhile, is estimated to be approximately £350 million.

The façade was made even more complicated by having to factor in movement within the truss that, on a warm day, can be 120mm longer than it is on a cold day. Movement had to be factored in throughout the building, crucially in its fire escape corridors. “We had to design a movement joint that was two-hour fire rated and could accommodate 150mm movement in any direction,” explained Martin who added how achieving this involved including a wall that spans the whole site that makes use of lumps of “un-burnable jelly.”

Inside, the first floor has been organised around an internal street, linking the reception to lift lobbies, atria and another entrance on the western square.

Progressing up through the building, which can be done as a member of the public too on its outskirts, there are a series of podiums that stagger incrementally at various levels. From this perspective, the building becomes one that manages to tap into London’s often forgotten history of pedways – elevated walkways originally intended to link people from building to building without having to descent to street level. Here, an extended orangey-bronze bridge reaches out to the Barbican, connecting to its ‘High Walk’ and creating a direct sightline from the Barbican to the newly pedestrianised Moorfields.

Looking at the building through Finsbury Circus.

The podiums have been filled with greenery; more than 20 per cent of the site area is now filled with bio-diverse habitats. The highest podium, known as the upper crown, hides within the “shadow” of a protected view of St Paul’s and houses executive suites, client meeting rooms and dining rooms.

From this vantage point, impressive views over the Barbican estate can be spied, while the other side of the building looks out onto Finsbury Circus: a vista in which, soon, a new development from British Land and GIC, designed by AHMM at Broadgate Circus will come into view: a development which, just like this, is looking to capitalise on the additional 1.5 million people the Elizabeth Line is bringing to Central London.

Credits

Additional images