Location: City of London
Completed Height: 288m
Architect: Kohn Pederson Fox
Main Contractor: Brookfield Multiplex
The Pinnacle project started with the demolition in 2007, Squire Energy was contracted to remove the six existing gas meters and to isolate the five gas services that entered the old buildings that were demolished to make way for the Pinnacle.
The next stage of the project was to divert an existing gas supply to an adjoining building as the supply ran through an area that formed part of the new development. After exploratory surveys it was decided that the only location for the supply to run would be on a gantry bridging the site 8m in the air. This service was rerouted using 4” welded steel and will stay on the gantry until the project is completed when it will be reinstated.
The Pinnacle requires a significant gas demand and this triggered reinforcement works of National Grid’s network, due to the complexity of the reinforcement works a design study was required to determine the scope and cost of the scheme. National Grid worked with Squire Energy to deliver the design study which concluded that a medium pressure gas main would be routed along Bishopsgate to an external pit based pressure reducing installation in the road outside the Pinnacle. From the pressure reducing installation a low pressure supply would then be taken into the basement gas meter room. An innovative design for the governor vents was created in order to hide the vent stacks within a decorative column under the atrium of the Pinnacle, the vents would then exit at the side of the columns with a small fitting.
As a medium pressure gas supply was utilised this meant that the low pressure service entering the building could have a gas pressure up to 70mbar rather than the standard 21 mbar. This elevated pressure meant that the internal pipework, some of which had to rise 65 floors could be downsized and it also eliminated the need for some of the boosters, thus adding to a cost saving.