The Swiss Re HQ, 30 St Mary Axe, designed by Foster Associates, was London's first ecological high-rise building with a natural ventilation system. It uses half the energy taken up by an ordinary air-conditioned skyscraper. Nicknamed 'The Gherkin' due to its unusual torpedo shape, its silhouette has become an instantly recognisable feature of the London skyline. This Computer Aided Drawing (CAD) shows how the plan of each floor is focused around a unifying central core and the circular perimeter widens towards the middle of the building before tapering at the top. This gives the building its distinctive profile, which is more elegant and takes up less space than a traditional rectangular tower block.
Computer Aided Design or CAD refers to the use of a computer in the design or construction process of a building. The computer can carry out more complicated analysis and calculations than were previously possible, allowing the architect to test the structure for weight bearing potential or resistance to external pressures such as the wind. Complex three-dimensional perspectives can be produced that can even simulate the experience of walking through the proposed building.