4 Cannon Street

4 Cannon Street is a medium-rise, high quality office development in the City designed by PLP Architecture for developer Pembroke. It was completed in 2019 and is located in a very sensitive site, between 3 listed buildings and close to St Pauls.

FMDC began working on the project in 2014, during the then equivalent of RIBA Stage 2, and continued engagement to completion on site, with a CMT service for the client. Mace was the Main Contractor, with Gartner and Grants as key Façade Sub-contractors.

The glazed elevations are framed by red sandstone piers and spandrels, which are of a faced precast construction, stacked from ground floor and restrained against the structure sequentially at floor levels above.

The stone is Plumpton Red Lazonby from Cumbria, the delivery of which was supported by FMDC’s Geologists, who visited the quarry and were engaged in the specification, procurement and range sampling process.

The unitised curtain walling is continuous behind the stone-faced precast piers and spandrels, as dictated by programme drivers, with Grants scope installed later, off the critical path. Lateral restraint rods, at floor levels back to primary structure, pass through specially designed apertures in the unitised spandrels, which are later sealed from inside the building, to complete the air-tight enclosure.