The development of 70 St Mary Axe (the “Can of Ham”) creates a stunning, semi-elliptical property, with c.28,000 sq. m (300,000 sq. ft.) of net office space over 21 floors, including a double-height foyer on the ground floor.
By 2015 the scheme was accommodating 2,800 people supported by a group of 10 machine room-less (MRL) passenger lifts. The lifts were configured so 4 of the 10 served the lower levels, and the remaining 6 served all levels.
The building’s external skeleton defines the building in a distinct manner, restricting solar gain. The lack of accessible roof space required an innovative approach to be considered to ensure safe access and maintenance of the building.
D2E were asked to review the VT scheme because the team were not yet confident in the ability of the passenger-lift group to achieve the Client’s performance targets. In addition, the design of the VT scheme had been based on advice for just one supplier’s product and the Client was keen to tender the package.
Nuveen’s primary requirement for the lifts was in compliance with the BCO performance targets. To achieve this the single advising supplier had offered an MRL product operating at speeds of 3.5m/s. D2E’s knowledge of the supply chain meant we knew this technology still in development and had not yet been proven in the field. Indeed, there were only two suppliers who had had MRL products that would operate at 3.0m/s even. This represented a significant risk to Nuveen. So D2E worked closely with the VT market leaders, the architects and Nuveen to develop a more robust scheme based around products that had successful operational history. D2E were also established there was enough headroom to accommodate machine-room products. This further de-risked the project for Nuveen by expanding the list of suppliers able to offer products, and by simplifying future maintenance strategies.
The VT package was tendered to three major suppliers in May 2015 as a 10-car group for which machine above and machine room-less options were requested. Three comprehensive offers were received back with Kone ultimately being successful. The Kone bid offered 3.5m/s and 2.5m/s machine above products that achieved the BCO’s recommended performance targets as a 10-car group.
D2E were appointed as the FA consultant to the design team to develop an access and maintenance scheme from developed design, through tendering and procurement to installation and handover.
In order to provide access to the external envelope, 1 No. Large reach Pantograph type BMU with bespoke powered roof opening system has been installed. The mechanically powered roof system ensures that the BMU is always concealed from view when not in service. Below the waistline of the building, a system of “soft rope” restraints carried by the cradle is employed to allow access beneath the overhang. The machine is also designed to allow glass replacement of up to 800kg in weight.
The system has been successfully procured, installed and is currently in use by the client.
D2E were appointed by Nuveen to continue working with all parties throughout the transition period from construction site through to occupation to ensure the equipment was handed over in first-class condition. This involved working with the main contractor and fit-out contractors to ensure the equipment was protected to limit damage.
JLL were appointed to manage the building for Nuveen and decided to continue the successful relationship with D2E by appointing D2E to manage the VT and Facade Access assets on their behalf. D2E have formed a successful partnership with JLL and Alimak to ensure; value for money through financial management of the contract, full compliance of all health and safety issues, an excellent level of performance from Alimak at all times and protection of the asset via detailed auditing.