Here, Simon Gregory, Sales Director at Proteus Façades, looks at how a combination of clever rainscreen cladding and architectural fins transformed a 1980’s building in London into Grade A office and retail space.
24 King William Street in London has achieved something that all refurbishments strive for but few achieve; creating a brand new building from the bones of an existing one and with minimal demolition. The design for this prominent site reuses the existing structural frame, with the end result being a building that is both elegant and refined. Outwardly, the solid and perforated brass, zinc and aluminium cladding panels, architectural fins and a wrap-around zinc roof come together to form an inspirational landmark at the Gateway to the City.
The £23 million renovation of this 80,730 ft² building, located on the northern approach to London Bridge, was designed by Ben Adams Architects and includes the addition of two new storeys. An elegant reception area comprises of a double height entrance hall leading into a lift lobby, finished with Portland stone floors and feature walls in marble and leather, with brass accents throughout. To reflect the style within, the architects specified Proteus SC TECU Brass panels and bespoke vertical fins and trim flashings, with an Artisan hand applied patinated finish for the ground level, street facing elevations.
These fins were designed around a rigid bespoke aluminium extrusion that connects to the curtain wall glazing system. The outer TECU Brass element of the fins are profiled in shape and taper across the length to generate an angled effect – the fins increasingly extend outwards as they ascend – whilst the connection of the material to the extrusion and the window frame remains constant.
The internal aluminium structure of the fins provides the necessary support and structural connection back to the curtain walling. This also created a depth at the rear, hiding the curtain wall system from plain view and giving passers-by the perception that the fins float in front of the glazing system. The combination of thin gauge brass material and internal aluminium support framework ensured that this element of the façade met budgetary requirements.
The fins are complemented by our perforated panels, which are fixed over insulated spandrel panels within the curtain wall system. These panels hide the ventilation elements of the curtain wall and fuse the fins and curtain wall system together. The panels were finished with the Artisan patination effect, which is created by applying a fine linear /orbital grain brush effect to the face of the brass material before chemical application and sealing. The panels will gradually weather over time and continue to embellish the already highly desirable warm ochre hues of the Artisan hand patinated finish, complementing the brass used internally within the reception area.
The rear elevation of the nine-storey building features Proteus HR Graphite Grey Rheinzink rainscreen panels. This zinc material then wraps up and over, forming a curved zinc roofing system which blends vertical and horizontal elevations into one. This particular material is gaining favour with architects and developers as it provides a long, maintenance-free life and offers adaptability to various design styles ranging from traditional to modern.
Once dominated by rambling plant rooms, the interior of the zinc roof is now home to state of the art offices overlooking the City and the River Thames. A limestone façade featured on the front of the building connects to the roof through our perforated flat sheets in a United Anodisers UnAtex bespoke finish. These panels are also integrated within the windows on the top two floors, providing an element of solar shading, and then flow up and onto the roof generating the patterned effect, while making is look like the façade and roof become one element.
Together this juxtaposition of materials has helped to bring an outdated and under-utilised 1980’s office building back into use; transforming it into a modern, aesthetically pleasing structure that stands out amongst many others in this prominent location within the Capital.
