In December 2015 Rogers Stirk Harbour + Partners moved into level 14 of the Leadenhall Building, which the practice itself designed. Rogers Stirk Harbour + Partners’ office move represents an innovation for all involved – a City tower is not a typical home for a leading architecture practice. However, the firm has moved right into the heart of its own portfolio, with its great view of the iconic Lloyd’s Building opposite.
RSHP gave careful thought to how to light their offices, and opted for a human-centric system that changes colour and intensity in accordance with outside conditions. And to deliver this innovative tuneable lighting method, the practice selected Iris, designed by Spectral.
Lighting was a key defining element and so was considered carefully early in the process,’ said RSHP project architect Maurice Brennan. RSHP appointed long-time collaborator Speirs + Major as lighting consultant.
Speirs + Major wanted the general lighting system to change colour temperature during the day, according to a predetermined profile corresponding approximately to the behaviour of sunlight moderated by atmosphere.
Maurice Brennan, project architect of RSHP’s office, discusses the importance of collaboration, throwing out the lighting rulebook and his colleagues’ response to the tuneable lighting:
‘Our intention from the outset was to avoid using a traditional suspended ceiling, and to expose the services and maximise the ceiling height as much as possible. To suspend light fittings from the ceiling would have added to the visual clutter, so we were advised by the design team that track mounting the light fittings would be a neat solution and significantly reduce the amount of cabling to power and control the lights. This is the only floor in the building to use this strategy.’
Iain Ruxton of long-time RSHP collaborator Speirs + Major reveals how they tuned the lighting to a Circadian cycle:
‘Both RSHP and Speirs + Major were keen to explore the use of colour-temperature tuneable white light in the studio, with the aim of adding a level of physical and psychological comfort to a space where the team often work long hours. The facility to mimic (or to deliberately differ from) the natural Circadian cycle of colour temperature is a hot topic in lighting, so the chance to try it out in a fast-turnaround project, with innovative architects as clients, was a great opportunity.
The initial programming of the control system delivers an approximation of the natural Circadian cycle, changing slowly from warm in the early morning to cool through most of the day to facilitate concentration, and warming up again in the late afternoon, providing visual comfort as natural light fades and the office moves into an evening working mode. The intention is to monitor how the team finds the lighting, and to adjust the behaviour of the system and experiment with different cycles if necessary.’