Liverpool Street Station: Roof Replacement Project

Sector context

London Liverpool Street is a Grade I listed, effectively subterranean terminus that works under strict underground-station fire rules. Replacing the train-shed roof cladding meant working above live platforms and running lines, on a 19th-century building, without interrupting one of London's busiest stations. Loads suspended from the fabric had to be managed carefully so the historic framework was not overloaded, a challenge Palmers and RDG Engineering had met before at Paddington, St Pancras and Kings Cross.

The challenge

Palmers' brief was to keep the station running as normal while the cladding was replaced across the full roof, using a lightweight suspended protection platform to keep the railway and its users safe.

• Suspended loads had to be managed so structural members were not overloaded on a listed 19th-century roof.
• Access had to keep impact on pedestrian flows to a minimum and meet strict fire rules for an effectively underground station.
• Works above platforms and lines had to fit planned possessions, including an eight-day closure of the mainline station over Christmas 2024.

The Palmers solution

Using its aluminium Bridge Panel frame system, Palmers designed and erected a series of lightweight, robust suspended protection platforms. They were launched from an erection gantry to the north of the train shed and rolled out along the roof during possessions to cover its full length.

• Each of the four spans has its own 50m suspended platform. They move independently, or combine to give a full 30m of overhead protection east to west.
• A bespoke Palmers platform roller system moves the large-span platforms easily through the train shed.
• Bespoke beam and spigot elements, derived from standard 750mm X-beams, take the load at the strong points in the existing roof steelwork, with pressed-metal decking keeping weight within the roof's loading parameters.