Renzo Piano Pavilion, Kimbell Art Museum
Fort Worth, Texas
Architects: Renzo Piano Building Workshop, kendall/heaton associates
Lighting designer: Arup
While the louver system opens and closes, it does not react to changes in sunlight throughout the day. “We didn’t want to sanitize the daylight so much,” said Andy Sedgwick, a partner in Arup’s building engineering team, which designed the project’s lighting scheme. “One of the special features of natural light is the fact that it is variable and it changes all the time. If you have a system that is too reactive you can kill that dynamism and you loose some of the special character.” It does however close completely during off hours and opens minutes before the museum begins accepting visitors. This cuts down on heat gain from the sun during the long summer mornings, reducing demand on the HVAC system.
As with the Kahn building, the Piano Pavilion features a mix of daylight and electric light. The tops of the structure’s 100-foot-long, 54-inch-deep, 8-inch-wide, laminated, twinned Douglas fir beams are outfitted with LED strips that project 3000K white light up at the bottom of the fritted, low-iron, UV-filtered IGUs that makeup the skylight. This maintains a gentle glow that shines down into the galleries during cloudy days and in the evening. Fabric scrims span between the beams, further diffusing the light.
The galleries’ art lighting is provided by a set of track-mounted LED fixtures from California company Xicarto. The luminaire provides high color rendering (95 CRI, which is phenomenal for an LED product) and show consistent color from fixture to fixture, even after years of use. “We’ve found it very compelling among museum professionals,” said Sedgwick. “They like it at least as much as tungsten halogen.” These are 3000K, which is apparently Piano’s favorite color temperature. “Everything that Piano does is 3000K,” continued Sedgwick. “We normally don’t have to ask.”