At 310 meters tall, the iconic Renzo Piano design redefines London’s skyline, with 87-storeys above ground and three below. RBG proposed and developed an alternative construction method (for frame contractor, Byrne Bros) which saved over four months on the programme and significantly reduced risk to the head client, Sellar Properties.

The jump-start core method supported the core with plunge columns while the basement and core foundations were simultaneously constructed below. This established tandem work fronts thereby minimizing the risk of delays in basement construction and allowing the superstructure to proceed significantly earlier than the original construction programme had anticipated.

Project Value:
£425 million GBP
Year Completed:
Building Metrics:
Total Area: 110,000 m2
Height: 310m
54,000m2 office space
16,000m2 hotel space
5,700m2 residential space
Levels: 87-storeys + 3 basement

Sellar Property Group
Byrne Bros (frame contractors)
Primary Contractor:
Renzo Piano Building Workshop
Robert Bird Group Services:
Construction Engineer
ICE Award Winner 2010

Key technical challenges

  • The primary tower structure consists of a composite slab and beam structure. Due to the long beam spans and thin slab, extensive analysis for footfall vibration was required to ensure the structure achieved code requirements and client expectations.
  • Working with the existing structure and developing design solutions that strengthened rather than demolished.
  • Extensive co-ordination with the mechanical engineer to develop a strategy that minimised beam penetrations and beam notches.
  • Differential shortening analysis with consideration of mega truss, steel structure, concrete structure and existing structural elements

Environmental performance

  • 5 Star Greenstar
  • 5 Star NABERs Energy and 4 Star NABERs Water ratings.

Key technical challenges

RBG redesigned the steel plunge columns enabling complex bracing arrangements and programme hold-points to be removed, hence simplifying excavation and improving health and safety. The ground floor slab was redesigned for significant construction loads and to prop the basement wall whilst maintaining a large void to allow the core to rise.

RBG also checked all permanent works elements for the temporary loads induced by the innovative construction sequence. The construction method further reduced the ground movements, thereby minimising the risk to sensitive network rail facilities adjacent to the site.

Contact Us

We're not around right now. But you can send us an email and we'll get back to you, asap.

Not readable? Change text. captcha txt

Start typing and press Enter to search