London presents its own unique challenges to those wanting to build tall. But the capital’s wealth of built environment talent is more than capable of providing the expertise required, responding with technical innovation and design flair.
Those were some of the key messages to emerge from a special half-day conference – Tall Buildings: how they get built, held at the NLA yesterday.
Skidmore Owings & Merrill director Kent Jackson kicked off by saying that architects had a responsibility to make their buildings sustainable, noting as an aside how Canary Wharf was definitely seen as part of London today. Jackson said that he felt that London had satisfactorily put tall buildings in clusters and that the appropriateness of the skyline was not so far out of line with the city’s far-off history; that there was an ongoing debate about whether the use of glass was ‘dead’; and a need to ‘make buildings simple and call in complexity when required’. He added that it was important to strive for high levels of efficiency in buildings – around 85% - and to design high end residential for end users in the mould of the double-cantilevered tower the practice is designing in Stratford for Manhattan Loft Corporation as a ‘vertical community’, with a series of amenities such as a hotel and open spaces ‘necklaced’ through the building.
Project Director for Wood Wharf at Canary Wharf Group, Robert Maguire, said it was amazing the speed at which an area such as Canary Wharf had transformed itself, from its beginnings in 1987 to its early growing pains associated with transport issues, to where it is today, 27 years later, as a location people go to, for leisure as well as work. Wood Wharf aims to build on the original SOM Canary Wharf masterplan of ‘places and spaces’, moving on from an early Wood Wharf scheme by Richard Rogers that concentrated on large office floorplates to a new Allies and Morrison masterplan which achieves ‘the right balance’ in homes, shops, restaurants and bars, and in placemaking terms. The plan includes One Wood Wharf, a competition-winning 57-storey cylindrical tower designed by Herzog de Meuron, which, said Maguire, ‘deliberately challenged our thinking of, and was a departure from, what Canary Wharf was known for’. Its unusual design, with ‘lofts’ at its base for families, balconies, long building programme of four and half years and other features, make the finances an issue, especially with values in this part of London well below those in the centre. ‘We all made a collective sigh in terms of the challenges of cost’, said Maguire, ‘but we’re committed to the building and think it will be a huge success because it’s unique.’
The conference also heard from Arup Associate Director Steve McKechnie, who demonstrated new structural engineering challenges and techniques which can enable clients to do more, for less. This included at 52 Lime Street – the Scalpel – where solutions included applying integral dampers to prevent oscillation, measures to create more floorspace without affecting the structure, and BIM, all of which delivered between £5m and £10 of value and savings to the client. Laing O’Rourke engineer Natasha Eversley-Robertson, meanwhile, showed similar levels of ingenuity used in the construction of the Leadenhall Building, where a new floor construction solution resulted in 50% less operations on site and 80% less labour. Other techniques included testing how to get plant into the building’s uppermost ‘attic’ element by using BIM and achieving some 80% of construction of the building’s elements offsite. Turner and Townsend Global Property Managing Director Steve McGuckin told the audience how his firm’s work on the Shard – ‘a vertical city’ – resulted in a million hours of accident- and injury-free working but also having to deal with the fact that it took workers an hour to get from signing in at the site entrance to their positions on the building every day. In a way, he added, the lag in getting tenants for the building was a good thing, since having 15 office fit-outs together would have been ‘a headache’. WSP Group Associate Director Richard Mawer added that the 306m-tall building features double-decker lifts and an innovative ‘hat truss’ system, while the construction process included practicing on a scale model of the Spire element in a field in Yorkshire. And finally, AECOM Cost Management Director James Barton reflected on the economics of building tall, saying that, typically, tall residential buildings add 1.5% to the cost of the scheme per floor and residential buildings cost between 30-40% more in total than their low-rise equivalents (25-40% with offices). Cost drivers include the buildings’ form, shape and technical complexity, iconic architecture and social recognition, balconies, services, lifts and logistics.
David Taylor, Editor, New London Quarterly