A TIMELESS DESIGN, EFFECTIVELY ILLUMINATED

The new Berlin U5 underground line is a prestigious project for the German capital, featuring: lighting technology from WE-EF in the stations. The 410 LED recessed ceiling luminaires, modified according to the designers’ ideas, shape the look of the station “Unter den Linden”.

The two Berlin boulevards Friedrichsstraße and Unter den Linden intersect above the new underground station, while the lines U6 und U5 cross through the station itself. In keeping with this central location, the architecture of the underground station has a spacious and prestigious design; the shell limestone wall cladding has a timelessly elegant look and references the historic façades of the local area where the same material dominates. From the 14-metre-deep platform of the U5, passengers look up through a wide opening along escalators over three levels. There, the existing U6 underground line crosses the new route directly below the surface.

Atmospheric recessed luminaires

The plans of the architects, Ingrid Hentschel and Prof. Axel Oestreich, provided for round recessed ceiling luminaires arranged in a grid pattern at the platform exits and the levels above. Together with the lighting design office, High Light, they designed a round acrylic glass cover as a characteristic detail for these luminaires. It has a sanitised underside for particularly soft and uniform light emission. The rim is clearly defined, the light emitted there softly illuminates the ceiling around the luminaire. As the cut-and-cover method was used to construct the station, cavities as neutral installation housings for the luminaires were created in the exposed concrete ceilings of the building shell – several years before the technical finishing. WE-EF convinced the planners with a coherent technical concept for these luminaires. The project-specific solution is based on DOC240 LED recessed ceiling luminaires, which make optimal use of the available installation space with suitable basic dimensions and modified mounting elements. Wide-beam LED optics uniformly illuminate the acrylic covers, which in turn are firmly bolted to protect them from vibration and secured by an additional wire cable.

Tailor-made mounting solutions

The panel luminaires above the escalator posed special challenges. The planners had planned for lift systems to be used from the outset, because ladders or work platforms cannot be used for inspections or regular safety checks. There, too, WE-EF provided a tailor-made solution: DAC240 LED surface-mounted luminaires with integrated electronic control gear – also fitted with acrylic covers – were mounted on luminaire lifts in the installation housings. The identical appearance and lighting technology of both luminaire types gives the lighting a uniform look in a 3000 K warm white. The timeless character of the space and the materials is complemented by uniform, soft lighting that meets the strict standards for transport infrastructure and yet also seems restful and calm – because “it is the users that make a station lively”, explained the station’s architect, Prof. Oestreich.

Project data

Principal: BVG Berliner Verkehrsbetriebe, represented by the Projektrealisierungs-GmbH U5
Architects: Ingrid Hentschel – Prof. Axel Oestreich, Berlin
Construction management: ignU5 – Ingenieurgemeinschaft Neubau U5
Structural engineering: SSF Ingenieure (shell); IB Krentel (finishing)
Light planning: High Light Berlin, Thomas Spreen
Completion: 2020
Photos: Frieder Blickle for WE-EF