© AKT II / Jan Friedlein
© AKT II / Jan Friedlein
© AKT II / Jan Friedlein

Two Pancras Square

This speculative Grade A office building within the prestigious Pancras Square development is located on a wedge of land between King’s Cross and St Pancras stations. It is one of six buildings within the overall development engineered by our team.

The 13,500 m² building has been designed by Allies & Morrison and features ten storeys of office accommodation, plus a two-storey basement. South-facing gardens adorn the rooftop, providing dramatic views across London. The design is environmentally conscious, incorporating an air displacement and chilled beam cooling system, with the intention of achieving a minimum BREEAM ‘Excellent’ rating.

Engineering the basement and structure has been one of our key challenges. On one side of the building, which is just 25 m wide, is a high retaining wall running along the main boulevard between the mainline stations and Granary Square. On the other side is a completely independent basement structure beneath the landscaped public space at the heart of Pancras Square.

This set-up leads to a major imbalance of forces between one side of the narrow building and the other, generating significant overturning moments in the core. This will be countered by the use of a large group of piles, up to 800 mm in diameter, to provide horizontal and overturning resistance.

The site also cuts through the base of a former gasholder, requiring significant remediation during enabling works. Where the gasholder was located under the building, it was fully excavated – up to 3 m below the proposed basement level – and backfilled with London clay.

Constructed using slender post-tensioned flat slabs, the building has been designed to maximise the amount of accommodation within its permitted height. The 9 m grid also allows optimum flexibility. Meanwhile, the façade features perimeter columns which step inwards at each floor level, providing a subtle tapering effect in the external pre-cast façade mullions and window profiles and access.

Ten-storey commercial office building in London’s Pancras Square

London, UK
Allies & Morrison
£ 40 million
FLOOR AREA13,500 m²
  • 2016 Civic Trust Award – Commendation