151 N Franklin St

Located in the bustling downtown Chicago Loop business district, the 35-story 151 N Franklin Street tower is billed as a ‘next-generation workplace.’ With that in mind, and concerned that the second floor terrace adjacent to a parking structure felt cramped and unwelcoming, the building’s owners sought to transform the terrace’s imposing concrete wall into a digital experience that would make the space feel more open, welcoming, and organic.

ESI Design conceived of a dynamic light trellis, called ‘Sensing Change’ which was further developed and implemented by upLIGHT and fabricated by Dimensional Worldwide. Winner of the IESNYC Lumen Citation for Interactive Façade, LIT Design Awards for Exterior Architectural Illumination, and IES Illumination Merit Award, 'Sensing Change' is a peaceful and reflective experience inspired by nature.

Situated on the terrace against the concrete wall, 'Sensing Change' can be viewed from within the upper floors, and street level. Live data feeds power the installation, creating a unique and continuously changing display day and night. The textured luminous trellis presents animations comprised of 390 bars of light playing patterns, colors, and motion shaped by local weather. Wind speed adds a layer of light over base states that include, Cloudy, Sunny, and Precipitation. Together, data and light produce over 250 abstract patterns of light reminiscent of water moving through leaf veins, rays of sunlight, and oxygen flowing through the atmosphere.

The trellis is made of brushed metal fins housing 500 Color Kinetics iColor Accent Compact and Color Kinetics iColor Flex LMX gen2 (now specificed with Flex Compact gen3, RGB) direct view luminaires – 4000 K fixtures face the viewer and RGB fixtures face the wall. Blending line-of-site and reflected lighting enables the sculpture to alternately appear as a single- or multilayer surface, for a complex and organic lighting effect. A controller connects the system to live weather feeds and powers the animations, including a Special Event mode, that allows building management to program and schedule distinctive color patterns and animation styles to mark local Chicago events and holidays.

With time, ivy planted along the base of the sculpture will climb the LED trellis, revealing the contrast between technology and the natural world and evoking the sense of dappled light through trees.