Architect wants to take you higher

Adrian Smith is the maestro of super-tall buildings. The architect based in Chicago worked as a lead designer with Skidmore, Owings & Merrill on four of the 11 tallest towers in the world, including Burj Khalifa in Dubai, the world's tallest building. Now his firm, Adrian Smith + Gordon Gill Architecture, is designing the 1-kilometre-tall Kingdom Tower in Jeddah, which will take the title of world's tallest when - and if - it is built. The much talked about Kingdom Tower, which at a height of one kilometre will surpass Dubai's Burj Khalifa as the tallest in the world, is scheduled to begin construction by January next year. Trump International Hotel & Tower, Chicago The 10th tallest building in the world added a new landmark to the Chicago skyline. Perched on the Chicago River, the 423-metre tower completed in 2009 includes a 225-room hotel, 472 residential units and 50,000 square feet of retail space. 201 Bishopsgate and The Broadgate Tower, London Set on a key site in London, at the centre of the Broadgate business district, the two towers combine restaurants, bars and retail space on a 2.3 acre site above the active rail lines. Burj Khalifa, Dubai The world's tallest building, completed last year, answered many of the questions facing tall building construction. The rounded, tiered design minimized the influence of wind at high levels, and systems were creating for the elevators, plumbing and other apparatus that had never been installed at such altitudes. Far from subsiding, the zest for building tall towers is continuing with fervour, especially in China, where Mr Smith's company is working on several towers of more than 600 metres. "There is no telling how far it will go," Mr Smith said in an interview with The National. "We keep seeing people wanting super tall. And they keep upping the ante." But while the industry continues to strive for new heights, the debate rages about the sustainability and eco-credentials of the tall towers. Critics suggest the buildings are more about ego than efficiency. Mr Smith, who will be in Dubai next Tuesday to address the Green Build Congress at the Dubai World Trade Centre, argues that skyscrapers are both eco-friendly and practical. What is the next challenge for building super-talls? I think architects and engineers can design buildings that will go even taller. We're working on a tower now that will go a mile high, as a prototype, not as a commission. But to see how possible it is. Once the building gets to be more than a kilometre, they get to be very big buildings, not only in height, but area. Primarily area. One of the limiting factors is how much area of [a] building can you put in [a] city on one time and market it successfully and have reasonable income or rate of return on investment. That's a big challenge. But that's not our challenge, it's more of the developer's challenge. Our challenge and the technical challenge would be as you get taller the elevator systems have to improve in order to get elevators to go higher in the building before transfer. Right now that limit is roughly 575 metres. So if it goes one kilometre, you start to get into a double transfer system. That begins to be pretty onerous in terms of how many elevator rides you're taking before you get to your destination. Those are the only limitations? Structurally we can go a mile high. We know that from a wind perspective we can design a building that will behave properly in wind conditions that exist in most cities. It basically becomes more than one building tied together. But it is possible. Are super-talls sustainable, green projects? A lot of people believe super-tall buildings are not sustainable. We are in [the] process of doing a research effort which looks at every typology of building - from super tall up to 200 storeys down to single family homes and just about every typology in between and evaluating the energy consumption required on a square-metre basis needed for each of those typologies. So far we're finding that the super-tall building is in the middle of the road. It's not the best-performing, but it's not the worst performing either. The best-performing tends to be something in the 40-storey range. And once you go higher than that certain other elements, like increased winds and lower temperatures, begin to impact the energy consumption in the building. But once you go less dense than that you get killed by additional surface area. So just from a building performance point of view, we think super-tall is justifiable as it relates to density of anything below 40 stories. Can you rationalise going above 40 storeys? In the ideal world, yes. When you go high-density you will encourage or almost mandate that the location be served by public transit. And when you go high-density with block after block, like the city of New York or Chicago, you have the added benefit of live-work environments where people can live and work in the same district. Is there technology that will make taller buildings more efficient? I would say in truth higher buildings are as efficient as a 40-storey. You are putting space above 40 storeys in a different kind of environment. It's location-specific to some degree. In Dubai [in Burj Khalifa], for example, it is 7 to 10 degrees cooler at the top of the building than at the bottom of the building. That actually helps you in Dubai because your cycle is mostly cooling. Whereas in Chicago that same principle applies but in Chicago in winter it actually hurts you because it is actually colder up there than on the ground. And your heating cycle takes over and you're losing more heat near the top of the building. The study is inconclusive at the moment. We're still in [the] process of fine-tuning a lot of these issues. But in general, I would say that they already are sustainable. Another part of the study is how much land you use for a super-tall building versus how much land you use for single-family or even a 40-storey. The land is valuable in itself. The more that can be turned into green belt the better. So you have to consider that aspect. twitter: Follow and share our breaking business news. Follow us

Architect wants to take you higher

Adrian Smith, the architect behind Burj Khalifa and many of the world's tallest buildings, says skyscrapers are efficient and eco-friendly. With video.