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Telecom Tower, London
60 Cleveland Street, Fitzrovia, London, UK
Telecom Tower, London
associated engineer
Ministry of Public Buildings & Works
date  July 1961 - opened 8th October 1965
era  Modern  |  category  Building  |  reference  TQ291819
ICE reference number  HEW 246
photo  © Christine Matthews and licensed for reuse under this Creative Commons Licence
Originally intended to be named the Museum Radio Tower, the erstwhile Post Office Tower is one of a series of telecommunications structures across the UK. Telecom Tower, as it is now known, was the tallest building in London until 1981, when the office building called NatWest Tower was built in the City.
Telecom Tower was designed by architects Eric Bedford and G.R. Yeats, and built by main contractor Peter Lind & Co. The design brief specified line-of-sight communication with other towers, and the necessity of sending signals over the Chiltern Hills north of London. Maintaining aerial alignment meant that firm foundations and a rigid tower would be required. A 1:67 scale model was tested at the National Physical Laboratory’s wind tunnel in 1961 to confirm the structural analysis.
Construction began in July 1961. The 53m deep foundation can carry a load of 13,200 tonnes and consists of a 27.4m square prestressed concrete base resting on the blue clay 6.7m below street level. It was the deepest foundation in London until 2004.
The tower’s cylindrical shape was designed to reduce wind resistance and, it was hoped, to withstand a nuclear blast 1.6km away. It can sway up to 1m in a shock wave. The hollow central shaft has circular cantilevered floors within.
The structure is 189m tall overall. The main shaft was constructed using slip-forming techniques to minimise high-level scaffolding. The core is 10.7m in diameter up to the 62.5m level, and 7.3m in diameter above that.
Between the 35.1m and 108.2m levels the tower’s exterior is clad with glazed panels, and has an overall diameter of 15.8m. Inside, this portion of the building contains radio, ventilation, refrigeration and power units. The power units provide an uninterruptible power supply to the building and its telecommunications facilities, which provide cover in case of a power failure until the on-site generators can take over.
The tower's 57 microwave radio aerials, antennae and dishes are positioned between the 108.2m and 145.4m levels.
Between the145.4m and 167.6m levels, six floors were dedicated to public access — presentation and function suites, kitchens and additional technical facilities. There is a revolving section, 19.5m in overall diameter, which passes through 360 degrees once every 22 minutes (0.17km per hour). Originally it was occupied by the Top of the Tower restaurant.
Above all these are the lift motors and water tanks. The tower is topped with the 12m tall London Weather Centre radar mast.
The two internal high-speed lifts travel at 6m per second (21.6 km per hour), and take 30 seconds to reach the top. Telecom Tower is the only British building legally allowed to be evacuated by lift rather than stairs — it has no proper emergency staircase.
The main structure was completed with the ‘topping out’ ceremony on 15th July 1964. It was opened officially by then Prime Minister Harold Wilson on 8th October 1965. The revolving restaurant was opened jointly by Sir Billy Butlin and Tony Benn MP at 3pm on 19th May 1966.
The tower cost some £2m to build and was visited by 1.5 million people in its first year and more than 4.5 million people by 1980.
In the early hours of 31st October 1971, a bomb exploded in the public area. Nobody was injured but the damage took two years to repair. The perpetrators are still unknown.
In 1980, the owners British Telecom (BT) stopped public access to the tower and closed the restaurant. The revolving section is now used as a hospitality suite for corporate events.
Until the mid 1990s, the tower was officially a secret — despite being so visible — and taking or possessing photographs of it was technically an offence under the Official Secrets Act. It was even omitted from Ordnance Survey maps.
Since then, the Telecom Tower has undergone major repairs to the external cladding and the lifts. The ground floor reception area has been modernised. In 2003, it received Grade II listed status.
Architect: Eric BedfordRenovation architect: Bailey Garner
Senior engineer: S.G. Sihan
Senior services engineer (M&E): J.J. Taylor
Resident engineer: N. Lampitt
Contractor: Peter Lind & Co
Site agent: E.P. Cronin
Research: ECPK
bibliography
www.lightstraw.co.uk
www.skyscrapernews.com
www.urban75.org
reference sources   CEH Lond
Location

Telecom Tower, London