Whilst tall buildings bring their own challenges, slender tall buildings add another dimension altogether. In the UK, as a building reaches skyscraper status (> 100m high), the wind and the building start to interact in such a way that the top of the building accelerates with the wind eddying off the build which can be very uncomfortable for the inhabitants. These effects are intensified on slender builds and bring a whole set of other issues too. A super-slender tall building’s width, which by definition has a height to width ratio greater than 12 means that the tension forces that have to be resisted at ground level are increased. The need to stiffen the building up to resist these wind forces is therefore essential and generally requires making the core walls and columns larger/thicker. In the 211 Broad Street project which has recently been granted planning permission, the building width is a mere 9.5m and this means that construction space will be at a premium! The solution adopted is to deploy a basement which has been brought about as the piling operations will be so restricted that we will in effect only be able to pile down the two long sides of the development leaving a perfect space to cite a basement.
211 Broad Street, Birmingham
