The Louvre-Lens is a 28,000m² art museum, a satellite of the Musée du Louvre in Paris. It's situated within a 20 hectare, ex-coalmine wasteland in the town of Lens in northern France, near the Belgian border.
The museum was designed by Japanese architects SANAA and New York studio Imrey Culbert. Arup worked closely with SANAA on the lighting design from the competition entry to completion, designing all daylight and electric lighting for the public areas of the museum and the external lighting for the surrounding park.
The entire 360m-long, low structure integrates into the site without imposing on it. It's made up of five steel and glass interconnecting single-storey buildings, the subtly curved facades of which are either glazed or polished aluminium. The park is reflected in these facades, ensuring continuity between the museum and the surrounding landscape. The roofs of the two main gallery buildings are glazed, both for bringing in daylight for exhibiting the artworks and for being able to view the sky from inside the building.
The scheme needed to be simple to operate and maintain and it was crucial that exhibition lighting be well-integrated with the architecture and provide maximum flexibility for accent lighting of the artworks. Additionally, daylight for the gallery spaces needed to be carefully controlled and direct sunlight minimised - as it can be damaging to exhibits. Flexibility to reduce daylight levels for low-light exhibitions was also a key requirement.
Natural light was at the heart of the design of the project, but as well as being an excellent source of light for art, it also has the potential for glare and excessive heat gains; so dealing with the varying levels throughout the day and seasons posed a challenge. Working closely with the design team Arup developed a gallery daylighting system that addressed a number of issues.
Daylight enters through the glazed roof. Above the glazing there is a fixed grating, the geometry of which was developed by Arup to ensure direct sun is blocked at all times of the day and year, while maximising daylight from the sky and ensuring good views of the sky looking north.
A skylight glazing is selected to filter out harmful UV while maintaining the excellent colour quality of daylight. Underneath the glazing are adjustable louvres, integrated with the roof structure and in a frame with the electric lighting track.
The louvres can be opened or closed to control the amount of daylight entering the space. For simplicity, these are manually operated only when required (different seasons, changing exhibitions), and do not constantly react to daylight levels. This means the daylight in the galleries is allowed to vary throughout each day, creating a more interesting, dynamic space, with a good connection to the external conditions.
Design excellence and innovation
Staying true to the design concept, Arup provided an integrated approach to the lighting – seamlessly fusing architecture, daylighting and electric lighting systems. The deep beams of the gallery roof ‘hide’ all the electric lighting from view – creating calm spaces where all light for the exhibitions appears to magically come from the sky.
The electric lighting for the galleries is simple and functional. A regular layout of lighting tracks holds exhibition spotlights as well as an array of ceramic metal halide downlights for ambient light to the galleries when there is insufficient daylight. Metal halide was chosen as an energy efficient, low maintenance, high colour rendering source, with flexibility in the choice of colour temperature.
LED technology advanced in quality and output enough that, late in the construction process, Arup pushed for LED spotlights. Therefore, all the exhibition lighting is LED with no halogen light in any of the gallery spaces.