Cooper, Robertson & Partners Architecture, Urban Design. Page 1. Daylighting: Flexibility and Conservation

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1 Cooper, Robertson & Partners Architecture, Urban Design Page 1 Daylighting: Flexibility and Conservation

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3 Daylighting: Flexibility and Conservation

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5 COOPER ROBERTSON Historical gallery design minimized daylight, maximized wall surface, and subsequently turned museums and visitor experience inward. When architects did introduce daylight into galleries, it came heavily filtered through skylights or clerestories. Deep spaces above functioned as mixing chambers, employing several layers of filtration and diffusion before light reached the galleries below in an acceptable range of foot candles. This system ensured that daylight would not damage sensitive works of art and that gallery visitors rarely had views to the outside. The new Whitney Museum of American Art represents a significant change in attitude toward daylight in galleries. The museum provides a seamless indoor/outdoor experience on each gallery floor with a variety of opportunities to experience the city beyond. Daylighting reduces the need for artificial illumination, allows works to be shown in the full light spectrum for which they were conceived, and accentuates the three-dimensionality of sculpture. Technology and careful analysis enables this new perspective while still preserving safe light levels and environmental conditions for the art. Use of glazing on all of the façades, and not just those facing north, demonstrates the design possibilities catalyzed by technological invention. Daylighting: Flexibility and Conservation Page 5

6 GLAZING, SUNSHADES, AND FLEXIBILITY The museum features glazed surfaces on each side of the façade. To enable the incorporation of this level of glazing, the team employed insulated glass units with warm edge spacers and clear, low-iron glass with neutral coatings with minimal reflectivity and extortion. A color-neutral PVB UV filtration inter-layer is sandwiched between the glass layers, filtering out in excess of 99% of harmful UV radiation. These measures protect the artwork from damage, provide enough protection on their own except from direct sun, and increase the building s energy efficiency. Frit around the window mullions ensures that no light seeps through when the gallery shades are closed Interior shades throughout the building allow for further modulation of daylight during bright times of day. These shades are deployed from the ceiling, covering the windows and doors. Roof-mounted sensors track the sun directly overhead as well as in four compass directions as it moves around the building. In bright sunlight, the shades are released, and on cloudy days or in the evenings, the shades are programmed to let in as much daylight as possible. To allow for complete control over the light entering through the windows, a four-inch wide graduated ceramic frit prevents light from entering the galleries through the one-inch gap between the shade and slender window mullion. If an exhibit requires full shading, the system can be programmed to remain closed. Gallery shade detail Page 6

7 COOPER ROBERTSON The interior shade system has two components: solar glare shades that cut down the intensity of light entering the windows, and solar diffusion shades that disperse the light that does manage to seep through. A robust tensile wiring system holds these shades in place to prevent fluttering. Many of these shades cover angled windows; the geometry of the system is precisely accounted. The shades work to cover light coming in from doors as well. The system, in addition to protecting artwork, allows for gallery walls to be painted a neutral white without reflecting glare. Arup modelled daylight illuminance falsecolor images from the same fixed viewpoint within a typical Whitney gallery space. Figure 26a. Level 6 perspective with no shades No shades Solar glare shades Figure 26c. Level 6 perspective with RB01 shades deployed Solar diffusion shades Both shade types Daylighting: Flexibility and Conservation Page 7

8 As an alternative to heavy light filtration through utilization of the shades which eliminates views out the windows a freestanding wall can be constructed to separate the glass wall from the main volume of gallery space. This could be used as a breakout space or for point of purchase retail, separate from the rest of the gallery circuit. For the first exhibition in the building, America is Hard to See, the museum constructed walls on either end of the fifth floor that feature non-light sensitive works and create resting spots with comfortable seating that afford visitors spectacular views of the Hudson River. The building allows the curators to change and manipulate daylight in accordance with exhibition and design programming. Eighth floor gallery with clerestory and window shade down Page 8

9 COOPER ROBERTSON Window shade installation during construction Daylighting: Flexibility and Conservation Page 9

10 Skylight R CLERESTORY MONITORS, GUTTERS, AND TARPS On the eighth floor, where saw-toothed, vertical skylights bring additional light into the gallery, the architecture incorporates clerestory monitors, one of the most effective and efficient systems traditionally used for screening incoming daylight in museum environments. However, the clerestories feature a mixing chamber that is only six to seven feet in depth, about half as deep than typical. North-facing to receive diffuse light rather than direct light, this complex system was carefully modeled and calibrated through extensive daylighting studies and also features sunshades that can close on brighter days. Inclined roof panels form a sawtooth north light system. These louvres are opened to the north and prevent direct sunlight from passing into the gallery space for most of the year, whilst allowing reflected and diffused sunlight to enter. The exterior surface of the roof louvres have a neutral matt finish to prevent specular reflections from sunlight. Low iron insulated glazing unit with laminated inner lite provide ultra violet filter. Low iron glass is used to maximise color rendering. Low-e coatings are used as neutral as possible in terms of color to maintain color rendering of the skylight glass unit of 97 or above. A motorized roller shade in a bottom-up configuration is used to provide a number of functions: Reduce daylight exposure outside museum open hours. Block early morning and late afternoon summer sun Regulate daylight transmission during museum open hours by varying deployment of shade. Skylight roof layers Figure 10. Skylight section Inclined roof p These louvres sunlight from the year, whi to enter. The be neutral ma sunlight. Low iron insu to provide ul maximise colo be as neutral rendering of t Motorised roll element is us Reduce hours. Block ear (see next Regulate hours by Page 10 Figure 11. Level 8 section

11 COOPER ROBERTSON Sawtooth roof line mockup Daylighting: Flexibility and Conservation Page 11

12 Eighth floor gallery with clerestory light monitors Page 12

13 COOPER ROBERTSON Daylighting: Flexibility and Conservation Page 13

14 The design of the Whitney demonstrates how a contemporary museum can flexibly accommodate daylight and views without compromising the requirements of artwork. The benefits of this approach are clear: a unique and distinct visitor experience; increased transparency as inspiration for citizens and living artists; and the city in use as an added layer in the curatorial narrative. Because of contemporary technology, the Whitney can be a museum completely connected to its surroundings. Page 14

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