Modern architecture in Israel, of which there is a rich and abundant history, has always had to contend with an obstacle that the progenitors of the style, entrenched in northern European enclaves, probably never considered when dreaming up their effete glass boxes: at times, 4,000 footcandles of blazing Mediterranean sunlight. As a result, practitioners of this school of design, as they have had to in other places such as Palm Springs, Calif., have had to develop a different set of forms and strategies centered around managing the powerful presence of the sun.
This trend has become all the more imperative in view of our contemporary insistence—both fueled by quality of life and environmental concerns—on making the utmost use of available natural light. Two new additions to Israel's premier art institutions—the Israel Museum and the Tel Aviv Museum of Art—are prime examples of innovative architectural solutions that use daylight in this sun-drenched climate.
Constructed in 1965 on a hilltop in Jerusalem, the Israel Museum's original architect, Alfred Mansfeld—a student of Modernist architecture—envisioned the institution as a Mediterranean hilltop village cascading down the incline. He accomplished this by establishing an 11.2-meter-square (approximately 120.6-square-foot) modular grid which set the parameters of his buildings' plans: They either fill out a singular modular square, are combined to form a two-square rectangle, or form a large square of four. These orthogonal volumes step down the hillside and create a varied skyline that recalls the indigenous architecture of the region. Unable to go with a Miesian glass box due to the sun and the fact that this is an art museum, Mansfeld clad his buildings in Jerusalem stone, a white limestone local to the region. At the very top, there is a band of tinted clerestory windows. The idea was that these would appear black during the day, letting in a controlled amount of natural light and creating an interesting contrast with the white stone. At night, they would become glowing beacons to announce the museum's presence throughout the city. Visitors arrived at a parking lot at the bottom of the hill, then proceeded up a stately 100-yard promenade to the entrance in a sort of pilgrim's procession not unlike the route up the Acropolis to the Parthenon.
Over the intervening years, Mansfeld's scheme grew a bit threadbare and out of date. For some unknown reason, the clerestory windows were painted over and covered with drywall shortly after the museum's opening. Also, the climb to the entrance has proved to be too arduous for elderly visitors who were not keen about the lengthy trek up the mountain in the extreme heat of the summer or cold of winter. So an additional access road was installed, which essentially cut the campus in half, dividing the buildings from the landscaped gardens. And, as happens with all robust and ambitious institutions, the museum's collection, which encompasses everything from ancient artifacts to contemporary sculpture and painting, wound up outstripping the available exhibition space. It was time for a makeover.
“We decided to pull all the nonexhibition functions out of the main envelope and house them in new pavilion buildings, creating a new entry, new axial movement, and a new central circulating point,” says James Snyder, director of the museum. To see this through, the institution hired two New York–based firms known for their deft understanding of light: James Carpenter Design Associates (JCDA) and lighting design firm Tillotson Design Associates. The brief was to create an architecture that would defer to the existing built environment while at the same time add a contemporary twist.
JCDA started by adhering to Mansfeld's 11.2-meter-square grid. But, where Mansfeld had felt the necessity to wall his buildings up with stone, Carpenter thought that there was a way, given today's technologies, that this could be achieved with glass cubes. “We wanted the new structures to be very open feeling and available to the landscape,” he says. To do this while managing daylight, the firm developed two systems of white terra-cotta screens that function similarly to polarized sunglass lenses. For the east-west elevations, the screens feature louvers that are angled to block light from the rising and setting sun. At the same time the louvers have scoops on top to bounce light off of the bottom of the louver above, where it then radiates into the interior. Views do not pass through these screens. The north-south screens have a slimmer profile and the gap between them is larger to open the interiors to the landscape, but still diffuse incoming daylight. The louvers are placed from between 0.5 meters (1.6 feet) and about 3.5 meters (11.5 feet) away from the floor-to-ceiling glass walls, creating breezeways that keep things cool. The strategy was so successful that JCDA was able to specify monolithic laminated glass panels (a low-iron glass with no green tint that offers the purest transmission of light) and even to reduce the amount of cooling equipment necessary to keep the interiors comfortable.
The new pavilions sit at both the base of the hill, featuring such functions as a restaurant and café, ticketing, and the gift shop, as well as at the top of the hill, functioning as the new entrance and central circulation point. To connect the pavilions and get rid of the pesky old access road, the team removed the existing promenade, dug a trench that features no significant rise in grade, and covered it over with a reinterpreted promenade. The underground passage allows visitors to approach the museum's exhibition spaces along a more or less level course and in air-conditioned comfort. Carpenter also brought daylight into this space by way of sunken courtyards separated from the tunnel by diffused glass walls and a glass-bottomed watercourse that runs along one edge of the promenade, allowing the shadows of the rippling water above to fall across the polished black floor.
At night, in honor of Mansfeld's original intention, the lighting scheme is turned on its head and the buildings and promenade become lanterns. Lighting designer Suzan Tillotson and her team explored a number of options for the pavilions, but in the end went with a simple grid of 150W halogen downlights with a variety of beam spreads that bounce enough light off of the floor to create a luminous ceiling. Lighting the tunnel proved to be a greater challenge. “The floor in the underground passage is very dark,” Tillotson explains. “We had to find a way to make it exciting.” The designers embedded flush-mounted MR16 metal halide fixtures behind the diffused glass walls to graze them. Similar fixtures wash the vine-encrusted walls of the courtyards. The MR16s also cast light up through the glass-bottomed water feature, generating a strip of guiding light alongside the promenade.
James Carpenter: Environmental Refractions, by Sandro Marpillero, Princeton Architectural Press, 2006 This is the first monograph dedicated to James Carpenter who is known for his work with light and glass. Working across disciplines, his exploration of transparency, reflection, and refraction takes on an architectural and a sculptural form.