London’s new City Hall was originally designed by Wilkinson Eyre Architects as a global sustainability showcase for Siemens. When it first opened in 2012, it was the first building in the world to achieve the highest possible ‘BREEAM’ and ‘LEED’ ratings for sustainable construction. The building’s refurbishment by ISG builds on these world-leading sustainability features, including updating the solar arrays which supply the building with renewable electricity and hot water, and upgrading the LED light fittings.
International design firm Arup was contracted by GLA to develop the event lighting. The design challenge was to create a high-impact night-time effect visible through the building’s highly glazed façade, while also providing interior ambiance. Key surfaces were carefully identified, including using the interior sloped soffit as a canvas to project colour wash light using colour changing RGBW LED lights to create an internally glowing effect at night for special events.
Testing the possibilities
Based on the Stage 2 design specifications, Architainment proposed a solution based on Lumascape lighting products that used Quadralux spotlights in some part of the building to deliver the high output power required, and Linealux LED grazers in the other areas. To demonstrate that the proposed solution would deliver the desired results, we set up on-site mock-ups in different areas of the building.
In the London Living Room, a single uplight was set up to reflect off the sloped soffit, allowing Arup to assess the light levels.
Columns in the Internal Street were initially to be illuminated with new in-ground lights replacing existing luminaires in the floor.
Continuous Lumascape L1 fixtures were proposed on the balcony to create the backlighting above the entrance.
In
the cafe and meeting rooms, the light effect was created by placing a Lumascape
L3 RGBW fixture along the bottom of the window.
Installing and commissioning
Following on from the successful demonstrations, the project moved ahead quickly and an order was placed with Architainment in October 2021. During installation and commissioning, there were a number of challenges that needed to be overcome, requiring some innovative solutions.
Early on, it was realised that the planned in-ground lighting for the columns would not work as displays mounted on the columns would block the light. This required replacing the in-ground lights with spotlights mounted above the monitors. Also, the position of the lights in the café and meeting rooms was changed from ground level to a reflected light source mounted above the windows to provide a better light result and make installation easier.
The most challenging part of the project, however, was the placement of the uplights in the London Living room. Initially, the Quadralux spotlights were fitted in a line as indicated on the Stage 3 design specification but this did not create a consistent light level across the sloping soffit.
Working closely with Arup and the installer, Winters Electrical, Architainment was able to align the spotlights to the optimum angles to provide the best coverage of light across the soffit. This configuration, combined with the programming skills of Architainment’s engineers, produced a consistent colour wash across the soffit.
Initial positioning based on specification.
Final spotlight configuration
and light effect.
The complete system is controlled with industry leading Pharos controllers, which were delivered in custom enclosures built by Architainment’s technical team. These are controlled remotely via Architainment’s cloud-based Archicloud solution which enables the light scenes for the building to be easily controlled and changed via a web-based portal for different national events such as New Year, Pride Day, NHS Day, Remembrance Day, Earth Day, and Christmas.
Final commissioning was completed in February 2022 and the results are amazing. As you can see in the images below, the final result clearly reflects the original design concept.
Concept
image:
Final result
