We owe the existence today of St Pancras International station to Sir Nicolas Pevsner and Sir John Betjeman who saved the station from demolition in 1966. It was statutorily listed Grade I in 1967 but soldiered on for many more years without major investment, underused and in neglected condition.
In 1996, it was decided to utilise St Pancras as the new London terminus for international services as part of the Channel Tunnel Rail Link (CTRL) project, now known as High Speed 1 (HS1). Substantial alterations were necessary to adapt the original Grade I listed building to its new use and, to facilitate this, the Channel Tunnel Rail Link Act 1996 disapplied the normal planning and listed building legislation. Environmental Minimum Requirements included a Heritage Deed with particular commitments to the restoration of the station. A Planning Memorandum included Planning and Heritage Minimum Requirements which set parameters against which the detailed design of St Pancras and its environs were to be developed.
London and Continental Railways (LCR) were appointed as Nominated Undertaker under the powers granted by the CTRL Act. The brief was to develop St Pancras with a defining vision to make the most of the historic building, signalling the return of the grand station to the UK and creating a 21st century transport interchange that celebrated the best of the past but with modern facilities to satisfy the most discerning of travellers. Foster and Partners were commissioned to prepare the master plan which was developed by LCR’s Rail Link Engineering team, a consortium of Bechtel, Arup, Systra and Halcrow.
The exceptional 400m length of the international trains meant that these could only be accommodated by positioning their stop blocks at the south end of the existing train shed and constructing an extension deck to the north of the existing shed. The East Midlands trains were accommodated on the western side of the extension deck and three new platforms for high speed domestic services from Kent were located on the east side. It was thus possible to create a new north-south concourse on two levels in the Barlow train shed with the original train deck cut away to link the two spaces.
The extension has been designed as a new and unashamedly modern structure. Covering all 13 platforms, it has an aluminium-clad louvre-blade and north light glass roof, floating above the platform deck and carried some 20m above street level on minimal vertical columns on a large 30m grid. The old and the new are separated by a glass transept more than 100m across and extending 22.5m from the north gable to the extension roof. The platform deck of the station extension efficiently combines precast and in situ concrete, using the platform edges as the primary north-south beams.
The Midland Railway, as the original builders of St Pancras, had brought the railway over Regent’s Canal and hence the track level was some six metres above street level. This created a huge undercroft below the station, used originally as a warehouse for beer brought down from Burton on Trent and which now provided perfect accommodation for the new arrival and departure halls whilst offering direct access to the railway above. To admit light and air, large slots were cut through the wrought iron train deck on the west side and smaller slots for escalators, travelators and lifts were cut on the alignment of each platform. The wrought iron girders and cast iron columns released by these slots were used to reinstate war and fire damage repairs elsewhere in the retained historic structure.
The major engineering challenge in the historic trainshed was to support the new loadings of the international trains whilst carrying the enormous lateral forces imposed by the roof arches around the new slots in the deck without wholesale removal of the original iron structure. The solution was a new 400mm thick prestressed concrete deck independent of the grid of wrought iron beams but supported by bridge bearings on the cast iron columns and tied into the base of the arches via a horizontal waling beam on the west side.
When opened in 1868, St Pancras station was the most opulent and technologically advanced of its era. It was designed to assert the supremacy of the Midland Railway over its rivals and it was the most splendid of all London termini. In restoring St Pancras, modern interventions have been designed to be subservient to the original architecture whilst enhancing its grandeur. A small palette of high quality durable materials, simply but carefully detailed, extends through both the original and the extended station, binding the two with the timeless quality of unobtrusive modern design.
The project has successfully secured the long term future of the historic station in continuing use for its original purpose whilst arresting of decades of neglect and removing damaging 20th century alterations. The original trainshed has been restored to as near original condition as practical whilst the disused formerly industrial undercroft has become a vibrant public space within the international terminal, with new vistas opened up to the trainshed roof above. The long term prospects for the station are now assured as part of a sustainable rail network.
The station is today celebrated as one of the finest examples of Victorian architecture and engineering, being received with great public acclaim and featuring worldwide in international media. It has become a destination in its own right, and has restored the glamour of rail travel.
Client architect: Alastair Lansley, Arup
Union Railways Master planner: Foster & Partners
Retail fit out architect: Chapman Taylor LLP
Eurostar Concept Design: Arup Associates, Land Design, Input Group
Client: Union Railways on behalf of London & Continental Railways
Contractor: Base build - CORBER (joint venture of Costain, Laing O'Rourke, Bachy Soletanche and Emcor Rail)
Contractor: Retail fit out - ISG InteriorExterior
Structural engineer: Rail Link Engineering
Services engineer: Rail Link Engineering
Quantity surveyor: Rail Link Engineering
Access consultant: Rail Link Engineering
Historic Buildings consultant: Rod Shelton
Trainshed lighting consultant: Claude R Engel