This September, we explore how developments in tall buildings are poised to revolutionise our cities and quality of life with leading architectural expert Antony Wood (Architecture, 1991), in the first of our new webinar series – exclusively for Nottingham alumni.
A specialist in the sustainable design of tall buildings, Antony developed his expertise as an architect in practice in Hong Kong, Bangkok, Kuala Lumpur, Jakarta and London. Now Executive Director of the Council on Tall Buildings and Urban Habitat (CTBUH) in Chicago, Antony is at the forefront of developing the next generation of tall buildings. We caught up with Antony as he prepares for the webinar to talk skyscraper safety, sustainable design, and what makes a tall building great…
The race to build the world’s tallest building shows no sign of slowing down. But is there a limit to how high you can build a skyscraper?
“There’s a consensus that a two-kilometre-high building is technically feasible with the technology we have today. But so far, there’s only one building under development even approaching half that height – the Jeddah Tower in Saudi Arabia, which is expected to rise to 1,000 metres.
“One of the biggest problems has been the amount of space elevators take up in a building. Because rope-hung elevators can only travel around 500 metres before the volume of the winding rope makes it impractical, it means you’d have to switch elevators at least once to reach the top of a 1000-metre building. People wanting to reach the highest floors don’t want to have to wait for elevators to stop at the dozens of floors in between. But this could soon change dramatically as new technologies allow elevators to move independently of each other in a shaft, without ropes, and to even go sideways or diagonally. At the CTBUH we’re already working on a research project to investigate the potential of buildings in a world of rope-less elevators.”
Following the tragedy at Grenfell Tower, concerns about the safety of high-rise buildings have arisen. How safe are tall buildings?
“In general, tall buildings are among the safest structures we can inhabit, simply because it’s hugely catastrophic if they do fail. Tall buildings tend to be heavily reinforced structurally against wind and seismic forces, and there are usually specialised strategies for preventing or limiting fire spread. Unfortunately, there are problems that need more attention.
“One is that there’s been a hesitance to retroactively apply new safety measures – such as sprinklers on each floor – to older buildings. Many places in Europe, including the UK, still don’t require sprinklers in high-rises – but that seems likely to change after the Grenfell disaster.
“Another is that the best safety advice only works when it has been properly implemented. It’s counter-intuitive for someone who is on a high floor to believe that the best thing for them to do in a fire is stay where they are and wait to be rescued. There should be a required and regularly reinforced safety education policy for occupants, coupled with a vigilant maintenance and testing regime.
“The issue with the use of low-cost aluminium cladding over insulation seems to be the most critical one, in light of the Grenfell and other similar fires. This type of cladding will need to be re-evaluated and removed from a large number of buildings because it acts like a chimney that spreads fire along the exterior of a building, defeating most of the other fire-safety strategies that protect tall-building occupants. It may turn out to be on a scale like the asbestos and lead-paint removal schemes of years past.”
With more tall buildings dominating city skylines, creating an iconic piece of architecture is just as important as height. So what makes a tall building great?
“It’s subjective – and is definitely about more than just height. In my view, it would have to be a building that is contextually appropriate to the climate, local economy and culture in which it is built. That means it uses a combination of the iconic power of height and the advantages of sustainable building practices. It could mean, for example, a shape that funnels high-altitude winds into turbines for electricity generation; a façade that modulates its opacity based on solar exposure and what’s inside the building; vertical greenery and sky gardens. The fact that we’re still building the same sealed-up all-glass-façade buildings in every locality around the world defies all logic and is environmentally irresponsible on many levels.
“The practical reasons for buildings having to be built a certain way, in a certain place, over time really need to be understood and interpreted into the buildings we design for tomorrow, because sheer historicism is just as inappropriate as a generic “international style” being visited on a place. It’s a huge civic responsibility, and it goes well beyond the commercial goals that made a building possible in the first place.”
What do you think the future holds for tall buildings? How will they shape society in the cities of tomorrow?
“It’s fair to say we’re likely to see more vertical development, simply because we’re rapidly urbanising as a species, we’re running out of arable land, and there is a growing recognition that sprawling development forms are unsustainable. I think the trend towards more greenery on tall buildings is something we should encourage – but we shouldn’t be satisfied with that alone. A radical re-think of city morphology needs to occur, in which infrastructure and buildings begin to merge, and cities have resiliency built-in from the start.
“Tall buildings have great potential to change how we live – the typology is only around 160 years old so we’ve only just begun to explore it. Most of what we’ve seen to date in terms of “mixed use” buildings stack functions on top of each other but keep them isolated – different entrances, elevator banks, access privileges. We need to start making more porous, more interactive structures that allow for fresh intersections between people, in the same way that the public street does in the old-world cities that we cherish. If we begin to think of tall buildings as a forest, a collective canopy that supports life rather than a loose collection of icons, then we move toward a society that is more in touch with technology, nature and itself.”