The St Botolph Building

Background Information St Botolphs House is a new build speculative office development in the insurance district of the City of London by Minerva plc, designed by Grimshaw, consisting of 560,000 square feet of lettable space over 14 storeys. The shell and core scheme was delivered under a Design & Build contract by Skanska. Speirs and Major designed the lighting scheme up to Employers Requirements before assuming a Concept Guardian role for the Client to ensure that the original vision was delivered. The lighting design scope covered both the exterior image of the building and all of the interior public spaces. The Exterior Image The lighting of the exterior of the building has been kept simple for both aesthetic and environmental reasons. The base of the building is lit by a single detail: downlighting provides not only amenity lighting but also soft backlighting of the columns. The crown of the building is described through gentle backlighting of the roof louvres. Connecting the two are the four glazed cores which form the exoskeleton of the building; these are given a presence entirely through their internal lighting. In order to drastically reduce energy consumption and light spill from the stairs within these cores, a dynamic control system was devised. When empty, the stairs are lit dimly for reasons of safety and aesthetics, but when occupied only the relevant parts of the stair are rapidly dimmed to full output. The resulting movement of light helps to animate the facades, whilst at the same visibly demonstrating the developers commitment to energy conservation. Finally, a single coloured element was incorporated: blue backlighting of the boiler flues, echoing the colouring of the cladding. This helps the building to retain its identity in the cityscape after dark. The Interior Concept The vast reception has been wrapped in light. A cladding system was developed in close collaboration with the architect into which the lighting was fully integrated, which covers all of the walls and also forms the balustrades. The system merges light with architecture and provides an elegant means to describe the curves and the level changes within the space. Matching white light has also been integrated into the escalators, which allows the downlighting to be progressively switched down during the evening heightening the dramatic appearance of the reception after dark. The spine of the building is formed by a huge lift system (consisting of eight shafts and 14 lift cars) which runs from the reception through the central atrium. In order to prevent the structure becoming too imposing within the atrium, the glazed floors of the lift lobbies and bridges have been underlit so that the physical appearance of the lift system is lightened. The custom-designed profile providing the uplighting also integrates all of the practical lighting for the lift lobbies to minimise the number of lighting elements. Above the lift system, the atrium is capped by gentle uplighting to the structure of the glazed roof. STPLCGrimshaw56000014 14underlit