One Coleman StreetEdit profile
The client brief was to provide a new office building, replacing an existing 1960's building to serve as the London headquarters for Legal & General, an insurance and investment company. The requirements included highly flexible and efficient column free office space, and enhanced sustainability credentials including the use of recycled materials and reductions in energy usage. The scheme set out to unite the disparate urban context of the eastern end of London Wall in the City of London. To the south and east of the site, the context is largely pre-20th century buildings located within the historic street pattern of the City’s core. To the north and west of the site the context is defined by post war development of parallel high-rise tower blocks set at an angle to the straightened London Wall and connected by the podium high-walk. Along with uniting these two disparate townscapes, the proposals for One Coleman Street set out to enhance the setting of the Grade II* listed Armourer’s Hall, directly east of the site, and the Girdler’s Hall to the south, by re-establishing the street wall along London Wall and Coleman Street, and through the creation of a new garden on the southern side of the new building. The structure consists of a steelwork frame of columns and composite cellular beams set out on 6m x12-15m orthogonal grid. The virtually column-free space is stabilized by bi-wall prefabricated concrete cores, and includes the use of recycled aggregates in the concrete. The exterior appearance of the scheme aims to exploit the unique characteristics of the building’s form. The scheme utilises polished pre-cast concrete cladding panels and polished stainless steel feature elements configured in a geometric arrangement derived from the curvature of the buildings floor plate but expressed through a series of interlocking and alternating triangulated surfaces. The fenestration is set at an angle to the edge of the floor plate, enhancing tangential views from the building while creating a robustly modeled surface to the external building face. This arrangement runs around the building to resolve the curvature of the floor plate while creating a directional movement to the façade with alternate floors arranged in the opposite direction. This opposing geometry is then resolved by the triangulation of the spandrel. The result is a richly modelled façade which changes its appearance continually as flat surfaces are used to resolve the buildings curvilinear geometry.