Basilica to Business: London Office Tower’s Historic Rework

Tourists know it as the building next to Harry Potter’s Diagon Alley. Office workers see it as a prime address for insurance giants. But for Hertshten Properties, it is a big opportunity. The family-run investment group, part of the global Hertshten Group trading empire, signed construction company Mace last month to move ahead with its bold new office tower in London. What began as the relatively straightforward redevelopment of 85 Gracechurch Street took an unexpected turn when archaeologists uncovered the remains of Roman basilica foundations beneath the site. Instead of derailing the project, the discovery reshaped it—bringing architects back to the drawing board to design not just another tower, but a civic landmark blending history, culture and workplace. ▲ Rendering of the exhibition space of the 85 Gracechurch Street tower. The original design for a 34-storey office tower has been reworked for an exhibition space in partnership with the Museum of London. There will now be a 32-storey tower on the 1605sq m site that includes end-of-trip facilities, an archaeological exhibition and new links to Leadenhall Market. The Woods Bagot-designed scheme uses a clever rejig of space to retain the originally proposed 35,000sq m gross internal area of A Grade office space. Hertshten Group director Ron Hertshten says they bought the property in 2016 as an investment simply focused on the location. “It’s in the middle of one of the busiest cities in the world ... it’s in one of the busiest streets in the city,” Hertshten says. “It’s a really tight spot to operate in and right next to Leadenhall Market, which is a listed market. “That micro area, all the insurance companies like to be there because [it is] right next to Lloyd’s of London. ▲ The entrance to Leadenhall Market and 85 Gracechurch Street to the right. “When we acquired the site it was nothing related to development, we just liked the building. “It was built in the 1930s, obviously a lot has changed since and it had served its purpose.” The group renovated the lobby and its long-term tenant grew considerably in that time but it became time to renovate or rebuild. “During Covid, it was a confluence of quite a few different factors that led to us thinking that there might be an opportunity to gain planning approval for this building,” Hertshten says. “There were several tall buildings that went up along that street and that’s the western edge of what’s called the Eastern cluster. “The timing was right from us from a commercial point of view, because we lined up a few of the leases. “It was right from the City [of London Corporation], for the development as there is one building that just went up and two more have consent.” Hertshten says the challenge was to create a building with a lifespan for another 80-plus years. ▲ Rendering showing inside the podium of the Woods Bagot-designed tower. Woods Bagot London studio chair James Taylor says they knew they had to do something special at 85 Gracechurch Street because of its historical context but that it had been a process. “We knew there might be archaeology but the working assumption was that the majority or most of it would be lost. But actually, we realised through the trial pits that there was quite a lot there,” Taylor says. “As an architect and as a Londoner it’s a ‘Wow, this is amazing’—this 2000-year-old history that we are revealing has the opportunity to be shown to the world. “At the same time, you’ve got the obligations professionally to your client, who’s thinking, ‘What does this mean? How do I make my building work?’. So it was quite a serious moment. “So we had to go back to the drawing board and look at how we could create, not public access only to level five but also to the basement as well, and so that’s a big design development.” Taylor says they reworked the plans to “make the stack more efficient” and they were confident they could do it. “To make the whole development viable you need the right amount of office to rent,” Taylor says. “We also need a really positive local authority and the City of London is really progressive in terms of what kind of buildings can happen. “The basement just couldn’t be as big, so all of the end-of-trip bicycle parking [600 spaces] and showers ... all of that moved above ground, out of the basement. ▲ Rendering of the tower from the street level. “Then you have these amazing showers and changing facilities that have natural light. “It’s a great advantage to the experience of the building but we had to find more office space in other ways.” The office space was found by removing unnecessary lifts and moving the office space lower within the tower. This created slightly bigger floorspace per level and simultaneously a more cost-effective tower with two fewer floors yet a similar leasable area. And while London may not be known for its sunny days, overheating from solar gains is still a problem so glazing has been reduced to improve its green ratings. ▲ Rendering of the new tower in the Eastern Cluster of the CBD. There is also more greenery and terraces on the tower, as is increasingly being included on towers around the globe, but with a Victorian feel to fit its relationship with Leadenhall Market. The end result is an all-electric building with a large civic public hall, publicly accessible heritage garden, exhibition space in the basement and the all-important flexible A-Grade office space. “This is really exciting for London because it’s the next of the towers that’s coming forward in the cluster ... as part of the next generation of towers of post-Covid stock,” Taylor says. “People want to come to work and really be proud of where they work, they want experiences that make it brilliant. They say buildings have to earn the commute.” Meanwhile, one of the Hertshten sons is moving to Sydney this year. While there are no immediate Australian plans on the horizon, there will be ears to the ground of the city’s commercial space.

Basilica to Business: London Office Tower’s Historic Rework

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