King's Cross Station Western Concourse roof
King's Cross, London, UK · 2006–2012 (overall redevelopment, concourse completed 2012) · £547m (overall redevelopment cost, 2012 prices)
The judgement call
Account-gated at launchThe central funnel structure provided essential support and structural independence from the historic Western Range building, also serving as a key architectural feature. - Extensive use of prefabrication for roof structure components to ensure quality and accelerate construction on a busy site. - Development of specialized connection rules by Arup and John McAslan + Partners to avoid visible bolts, preserving the aesthetic purity of the roof's form. - The decision to limit glazing to 15% of the roof area to mitigate solar gain, which, while environmentally prudent, was noted by some critics as potentially undermining the spatial impact and visual integrity of the concourse.
Key engineering challenges
Designing the concourse to fit between Grade I and II protected historic buildings without placing any load on them. - Integrating the new structure with existing underground tunnels and railway infrastructure on a highly congested site. - Designing a complex diagrid shell structure roof with perimeter tree columns and a central funnel, structurally independent of the sensitive Western Range building. - Managing construction on an operational railway station.
Project facts
- Client / owner
- Network Rail
- Lead contractor
- Vinci (main contractor), Seele (Western Concourse roof structure and cladding)
- Lead designers
- John McAslan + Partners (architect), Arup (structural engineer)
- Project type
- upgrade | new build
- Scale
- 8,500m² concourse; 130m-wide half-dome roof; 16 steel "tree" columns; 52m uninterrupted span; 20m high. Europe's largest single-span station structure.
- Disciplines
- Structural; civil; architectural; heritage engineering; lighting design
- Standards & frameworks
- UK Building Regulations; Network Rail standards
Sources: Building: King's Cross Western Concourse: Space Travel (https://www.building.co.uk/buildings/kings-cross-western-concourse-space-travel/5032915.article) - Arup: London King’s Cross station modernization (https://www.arup.com/en-us/projects/london-kings-cross-station/) - New Civil Engineer: King's Cross station roof revealed (https://www.newcivilengineer.com/archive/kings-cross-station-roof-revealed-10-08-2011/) - Architect Magazine: King's Cross Station Western Concourse (https://www.architectmagazine.com/design/buildings/kings-cross-station-western-concourse_o)