Constructed between 1982 and 1986 by Alfred McAlpine plc for Vickers Shipbuilding and Engineering, DDH was built on land that was created by infilling part of Devonshire Dock with 2.4 million tonnes of sand pumped from nearby Roosecote Sands. The purpose of the indoor shipbuilding facility was to protect vessels from external weather conditions and prevent satellites from photographing secret technologies involved. In the late 1980s and early 1990s it was known colloquially as "Maggie's Farm" in reference to the then Prime Minister Margaret Thatcher, who opened the facility, and whose Conservative Party government were upgrading the UK's submarine-launched nuclear weapons from Polaris to the Trident systemon boardthe boats. DDH provides a controlled environment for ship and submarine assembly, and avoids the difficulties caused by building on the slope of traditional slipways. Outside the hall, a 24,300-tonne capacity shiplift allows completed vessels to be lowered into the water independently of the tide. Vessels can also be lifted out of the water and transferred to the hall. The shiplift was the largest in the world upon completion. The first use of the DDH was for construction of the Vanguard-class submarines. The shipyard is currently constructing the s the first four of which were launched in 2007, 2011, 2014 and 2017. As of 2017, the Royal Navy submarines and are under construction inside Devonshire Dock Hall.
Structure and dimensions
The steel frame DDH is the tallest building in Cumbria at and could be described as a 'Groundscraper' having an overall length of, width of and an area of - over 6 acres. DDH is the second largest indoor shipbuilding construction complex of its kind in Europe after Dockhalle 2 of Meyer Werft in Germany and is visible from miles around, most notably from the Blackpool Promenade which is over 20 miles away.
Future expansion
DDH is at the centre of a £300 million redevelopment of the shipyard that commenced in late 2014. A large extension to the hall is under-construction to enable construction of the Dreadnought-class submarines, the replacement for the existing class of SSBNs in Royal Navy service. Proposals were also put forward in 2019 to re-clad the DDH in its entirety to extend the lifetime of the building. The projects are the largest investment at the shipyard since the construction of DDH itself.
