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21m-news-post-image-min

It’s great when a plan comes together!

Exciting times at 21 Moorfields as the final piece of lightweight concrete is cast onto the roof of the 17 storey 16,000T steel frame on 9th September 2021.

Developed by Landsec with Structural, Civil, Geotechnical and Construction Engineering design by Robert Bird Group, the building will provide ~600,000sqft of premium office space, and is due for shell and core completion by Sir Robert McAlpine in 2022.  The building is located directly over London Underground’s Moorgate Station platforms, Crossrail’s running lines, and the Moorgate Station Entrance to Crossrail’s Liverpool Street Station.

Maintaining station operations throughout construction was imperative, and the complex underground constraints left little space for foundations.  Robert Bird’s solution for a 60m span ‘bridge’ building is founded on 70m long large diameter monopiles located within negotiated back of house station areas.  Foundations were piled within steel sleeves through the station from a bespoke piling grillage sat on the station roof.  This method enabled the station to remain fully operational with very little noise or disruption from the construction process.

RBG’s philosophy of integrating a carefully considered Construction Methodology and Erection Sequence started with our concept for piling and frame erection at site purchase in 2013.  Architecturally integrated launching trusses within circulation spaces of the lower levels are used to erect the efficient long span arches at level 10 without overloading the station roof.  Arches are typically hidden within vertical cores, entering office floors at levels 7-10 only.  The result is a highly flexible commercial office building with an efficient structural frame, minimised temporary works and maximum developed area above an extremely complex underground asset.

Our team are immensely proud of what we have achieved, and we look forward to seeing the Shell and Core completed next year, and fit out thereafter.