'Sustainable cities and tall buildings' report part two

Image: EDGE building, near London Bridge, courtesy of Pilbrow & Partners

In the second part of Future Cities Forum's report 'Sustainable cities and tall buildings' the focus is on the development of the EDGE building near London Bridge with contributions from Pilbrow and Partners, developer Edge and Mace Construct.

EDGE London Bridge, situated within the emerging tall-building cluster near The Shard, is set to be one of the country’s most sustainable tall buildings. The first UK project by pioneering real estate developer EDGE, the slender 28-storey tower will offer exemplary workspaces to both established businesses and local start-ups.

The building’s open, four-storey plinth will comprise a publicly accessible lobby, café, auditorium and free flexible workspaces. It will also provide tenants with accessible outdoor spaces including a new public park, planted balconies and a shared roof terrace, plus a fully equipped gym and over 500 cycle storage spaces

Edge Director, Alex Kerr, spoke about his experience of studying Dutch ideas on planning tall buildings while in Amsterdam:

'I think it's fair to say I've been at Edge for just over a year. I spent twelve years at CBRE, prior to that working for a very wide range of landlords on new builds, refurbs, big, small, pretty, ugly. I was working with Edge on 125 Shaftesbury Avenue before I left CBRE, and we got taken over to Amsterdam to go for a tour of their buildings, with all the consultants involved with 125 Shaftesbury Avenue. Naively, arrogantly, I spent the last twelve years looking at a huge range of buildings in London, whilst I was very interested to go and see what Edge had developed across the city of Amsterdam.

'I have to say I was, after probably three or four buildings, three or four different inspections, and saw the breadth of what they've delivered over there and it is very varied, it's high-rise, it's low-rise, it's refurb, it's new. And I saw a certain sort of design element that I just had not seen in London, perhaps just consistent use of natural materials. I was really inspired with quite how thoughtful they are around design of buildings, whether that's for the end user or in terms of how the buildings are designed and ultimately built.

'I think the one thing that I find particularly interesting bringing it back to London Bridge is Edge's dedication to delivering large-scale new-build office accommodation, but also having absolute regard to that embodied carbon piece when it actually comes to delivering it. That's why I speak to a huge range of occupiers on London Bridge. Some care more than others. Certainly around the embodied piece, it's always quite interesting pitching the embodied carbon piece to an occupier because some of them, quite simply, will say, well, actually, that's to your benefit. You're the ones that have built it, it's got your name on the front door. For us, really, the operational piece is more important.

'But you do get occupiers who, when I say to them that we're targeting 600 kilograms of carbon per metre square on a new-build tower, that, with the right audience, really does strike a chord. I think that is just a very easy design element to point at that does demonstrate Edge's commitment to that kind of responsible development and also looking at things in a slightly different way.

'In all the previous new-build towers I've worked on, they were predominantly glass and steel structures. I think you will see certain design elements such as the concrete structures, such as the fact that 23% of the floor space in the building is timber. It's those very interesting design elements that are all from our experiences in the Netherlands of designing hyper-sustainable buildings. We've brought some of those learnings over to London, and it's an absolute pleasure talking people through the building, whether it's occupiers, whether it's groups such as this, talking them through what we're doing.'

Image: EDGE London Bridge under construction in November 2025 with Chapter Living on right

Alex was asked about the amount of greenery the building would be holding to help with the occupiers' wellbeing but how difficult it might be to manage as it grows:

'So there will be, certainly on arrival, there is a significant amount of greenery. So we're delivering green space in between us and the building next door, which, again, you won't really be able to see where it is, and you won't be able to understand how it will be delivered today. That greenery follows you into reception, so we'll have a big green wall in the reception.

'Certainly as a leasing agent, I've worked on plenty of schemes where this concept of the green wall and greenery reception and the benefits to health and well-being are great, but when it dies, it is just the most miserable sight of all time. And so we've worked very hard to make sure that even down to which species of plant are in which part of the wall, depending on the lifestyles we've conducted, we're pretty confident that that will survive. And down to the irrigation system, again, making sure that if you have some plumbing, if you lie behind and you get an airlock in any of that, then you're in real trouble. So the design of that has been very, very well thought through.

'The delivery of greenery and reception will be prevalent, but thereafter, it is reduced. Every other floor has terracing. There will be a tree on each terrace. There is more greening up on the top floor, which is a private terrace for one of the occupiers that's actually now signed. But there will be a green theme on the way into the building, but it's not entirely, but it almost ends after that, because we are in control of it, and we have designed it so that it is maintainable. But I think thereafter, you don't come out of lift lobbies and see more greenery. It's where we can absolutely control it and where we think it will have the greatest impact, but it's not just sprayed across the building.'

Image: CGI from Pilbrow & Partners - View of the proposed new garden framing the important view of the Church of Lady of La Salette and Saint Joseph

The building claims to have generous shading and chilled ceiling panels too and the conversation turned to Fred Pilbrow of Pilbrow and Partners to ask about his experience of working with the developer Edge with the demands for more environmental concerns in designing buildings:

'It's been great, and actually Edge have been a wonderful client for us, because they're super ambitious, super restless, super dissatisfied, and always trying to do more. I think my colleague Andrea, who's been at the sharp end of this, has been working closely with Stuart and his team at Mace, and it's like never good enough. We've always got to push and push and push and make things better. I mean, I guess when we first collaborated on the project, I think Edge found us through an interest as an architectural studio in integrating environmental concerns into our architecture. We built our own in-house resources to enable us to evaluate in real time the kind of consequences of architectural decisions we were making.

'I think when we started work, we did a little study that made a small change that I think hopefully when we look at the site today, you'll see the consequences of, which was that the Columbia Threadneedle, who owned the site before us, had proposed a building on St Thomas Street, which is like the front of the site, and had a garden at the back, a garden that was therefore hidden for those coming out of London Bridge Station. We wondered whether you could spin that relationship, draw the building to the east of the site, and make the garden everyone's first arrival experience coming out of London Bridge Station.

'Rather beautifully, the garden then flows into the foyer and the spaces we were describing. I think the garden also unlocked permeability to Bermondsey, and one of the things that I think was really resonant for me, working with, for example, local authorities, Southwark, and the local community, was that Edge's sustainability interests really resonated. I think Southwark were quite proud to have what we believe will be the most energy-efficient, multi-tenant tall building in their borough, and I think that support was critical.

Equally, Edge's openness to the local community was really distinctive. So we worked with Snowsfields Primary School around the corner, we refurbished their playground, we did a sequence of sessions on sustainability. But that's a relationship that will endure when the building opens. So, for example, the wonderful lecture theatre that you'll see that looks out over the garden will be available to the local community to come do Christmas pantos for the school. And I must say, when Edge posed that to me, I thought, you're mad. We're going to have all of these blue-chip tenants. They're not going to want to see crocodiles of school kids coming into the foyer. But that's not been the experience at all, actually. People are really excited about that and really welcoming. It is a kind of Dutch ground floor, and like the buildings in Amsterdam, it's going to smell great, there'll be great coffee, and it's sort of informal and relaxed. Interestingly, the market was ahead of, certainly, my conservative expectations in welcoming those innovations.

'Edge are also unusual as a client because they're doing a lot of their own research. The system, and in a way, this drove the decision to pursue the post-Edge in concrete and timber, their own research suggested that displacement ventilation was both more energy efficient, but also had significant health and well-being benefits. We have generous air volumes, there's less air mixing, it's quieter, we think it doesn't spread. If one person has a cold on a floor, it doesn't get to all their colleagues.

'And then there's a chilled ceiling again, integrating bespoke sensors that Edge themselves developed, looking at occupation, air quality, temperature, humidity. And the air quality, for example, is monitoring the amount of CO2, so if a room feels a little stuffy, we'll deliver more air. And that's stuff that Edge themselves pioneered and developed in-house. And for us as architects, it's been an absolute privilege to work with them. And that sense of collaboration, I think, has been a bridge to our working with Stuart and his team at Mace, who remorselessly improved the embodied carbon and looking at the operational efficiency.'

Image: view from terrace at EDGE London Bridge towards the Shard (courtesy Pilbrow & Partners)

Stuart McDonald, Project Director at Mace commented on the research carried out by Edge and the impact on the way Mace might construct in the future:

'The real challenges for us, as Fred has outlined, is when you get to the place where you think that's a positive answer, what could you do more? And it's probably the most forward-thinking client I've ever worked for in the industry. And the challenge has been very clear about that's good, but what's next?

'A couple of examples that are probably exciting would be, from a carbon perspective, the building has currently got a monitoring system and files and a graph in some of the B4 areas of the building. And the reason we did that for the benefit of future schemes. It tells us how the building's performed in a live and a dead situation in terms of the local supply. And ultimately, it will allow us to then take a better view when we're looking at the safety factors in the carbon design and future schemes where we're in the London Plan environment. And EDGE is on its third scheme now, at Shaftesbury Avenue.

'The second scheme, EDGE Liverpool Street, is probably going to benefit around 2,500 cubic metres of concrete saved as a consequence of the remapping of the building. So it's not just about what we're doing now, but what can we do now to help in the future as well.

A large amount of clay was salvaged from the foundations of the EDGE building and Stuart described the value of that:

'I can certainly comment on the clay. Four-storey deep basement, we've come across a lot of clay. And we were staring at it, and it really was high-quality material. And essentially, we did everything we could to try and use it in terms of fill. The area's quite small. Some of it went to our sister company, our sister site, Chapter Living, next door. But we got talking, as we did, what we're going to do with this because it's a great product. And, gratuitously, Abigail was mentioned. Abigail is a potter, essentially. And the conversation then developed, well, what can we do with this? How can we bring this back into the building? Continuity developed along those lines. So that's currently under manufacture now, and you'll see evidence of that when the building is finished.'

Image: Reviewing the facade terracotta tile samples for EDGE London Bridge in the sun - courtesy Pilbrow & Partners

Fred added:

'To clear an interest, Abigail North is my sister, as well as a fabulous ceramicist, and she'd helped us on the prototyping of the really beautiful green façade that you'll see that looks out over the garden. And so Mace knew that she was good with clay, and Stuart sent her 20 tons of clay from the site, which she spent about a year sifting and cleaning. The wild clay is really beautiful. So when you have to fire it at quite low temperatures, it won't go up to stoneware temperatures, but it produces this really kind of soft terracotta colour with a white bloom. It's absolutely beautiful. And you can't get that from a commercial clay, so it's something that was possible from the found clay of the site.

Pilbrow and Partners state that the tower's expressed structural frame honours Bermondsey's Victorian engineering heritage:

'Inside, the design fosters vertical connectivity, promoting interaction across levels, with flexible CLT floorplates allowing for adaptable internal configurations. The compact plan is designed to deliver generous daylighting and panoramic views, while the high-performance glazed terracotta elevations will optimise shading and minimise solar heat gain and glare.'

Fred continued:

'One of the things I think we were interested in doing as architects was to make something that was legible and you felt the real materials that made the building. And I think when you look around, you can see the timber, the concrete. And the structure is interesting because we wanted to deliver really well-connected open floor plates. The core is drawn towards the east. Coming onto the core, you see the whole of the floor plate in one place. AKT, our structural engineers, said that poses a problem because although the core is the primary stability, the plate being eccentric to it will rotate. And so we resist that rotation with a series of braced bays on St Thomas Street. And it's not exactly Victorian, but there's a certain enjoyment in the scale of that and the kind of pleasure that the building breathes beautifully from a distance - but close to Victorian, I'm not sure.'

Image: The entrance lobby includes vertical planting – trees, climbing plants and green walls that extend between floors

courtesy of Pilbrow and Partners