Aluminum: On the Cutting Edge of Urban Design

Civic architecture, and the materials used in its construction, is a product of its time and place—whether the brick of colonial Williamsburg or the Gothic stone cathedrals of medieval Europe. And though many magnificent examples from such past eras endure today and are revered for their historical value, time and technology move on—and new materials and architectural styles are essayed.

With respect to the architecture of commercial buildings, a major break from the past occurred with the establishment of steel-framed buildings in the late 19th century. The Home Insurance building, erected in 1885 in Chicago, is generally credited with being the first “skyscraper” to use this technology. Freed from the constraints of using the exterior walls to support the weight of the structure, buildings could—and would—become ever taller and forever change the urban landscapes of America and the world.

Aluminum, whose commercial discovery was roughly simultaneous with this development, would become a major feature of this newer generation of monumental buildings. Aluminum cladding would grace the exterior of Chicago’s Sears Tower as well as its John Hancock building—and aluminum curtainwall would become a standard construction technique by which to allow generous amounts of light into the interior of large urban buildings.

Today, a range of factors are weighed in determining material selection for civic monuments, including appearance, durability, formability, weight, recyclability, and ease of fabrication, shipping, handling, and maintenance. Aluminum’s high performance in all these areas is behind its continuing popularity among architects who design such buildings.

Michael Lee-Chin Crystal
What may rank as the eighth wonder of the modern world opened in Toronto earlier this year—and it’s a showcase for aluminum. The Michael Lee-Chin Crystal building—an addition to the century-old Royal Ontario Museum—almost defies description in its vision of the future.

The building, dubbed the “Crystal” for the jagged lines and shape that make it resemble a gemstone, contains only one vertical wall and no right angles. Over 18 miles of aluminum extrusions (equivalent to 90,000 square feet) are hung from its structural members to create a glistening gem of an exterior, offering striking profiles by both day and night.

Among the most unusual aspects of the building is its resemblance to architect Daniel Libeskind’s original drawing—which he conceived on a napkin while attending a family wedding at the museum. Inspired by the museum’s gem collection, he sought to replicate their rough-cut shapes in the design of the museum addition itself.

Initially, Libeskind’s design called for the building’s exterior to be half glass and half aluminum. However, concerns about budget overruns—as well as for the preservation of the artwork which would be displayed in the galleries within—led to its ultimate configuration of 75 percent aluminum and 25 percent glass.

The extruded brushed aluminum cladding—in a warm silver color—is the topmost of three layers that together are three feet thick. The bottom layer is a moisture-proof seal insulating the building against Canada’s harsh winter weather.

The aluminum extrusions that form the top layer were manufactured and installed by Josef Gartner Co. The extrusions—roughly one-foot wide by four inches deep—are positioned with gaps of approximately two to three inches between. They are designed to ensure that water and snow are channeled off the exterior’s surface to prevent large sheets from cascading down on the sidewalk below.

Having to navigate the building’s sloped walls and difficult angles during installation of the extrusions, construction workers had to train in rapelling (i.e., like mountain climbers) in order to complete their work.

“The Lee-Chin Crystal . . . is intended to transform the ROM into an inspired atmosphere that will promote the resurgence of the museum as the dynamic center of Toronto,” Libeskind said. “It is my hope that the Lee-Chin Crystal, as well as the other components of Renaissance ROM, will become a focal point for the city and people of Toronto, a place of wonder and joy,” he added.

Although it is not obvious from the vantage point of the street, the five interlocking, self-supporting prismatic structures that comprise the Crystal do not attach to the original ROM building (except for the bridges that link them). Nevertheless, the bold modern addition crowds over the ROM’s older stone and brick buildings—a fascinating juxtaposition of old and new.

New Museum of Contemporary Art
When the New Museum of Contemporary Art opens its doors December 1, it will represent the first time in the venerable institution’s 30-year history that it will occupy its own freestanding, dedicated building. New York’s only museum focused solely on contemporary art will also occupy a new address—moving from its former location in the West Manhattan neighborhood of Chelsea to its new home on the Bowery.

And what an addition to the neighborhood! Sejima + Nishizawa/ SANAA’s seven-story aluminum-clad structure is a gravity-defying tower of stacked boxes that immediately calls attention to itself without overwhelming its surroundings.

The young Japanese architects chose a custom expanded-metal aluminum for the building’s exterior. The highly reflective silvery-white aluminum for the mesh was sourced in Belgium, fabricated by the Expanded Metal Company in the U.K., anodized by the London-based firm of James & Taylor, and installed by M.G. McGrath of Minneapolis.

The distinctive form of the New Museum building—with its off-kilter boxed approach—derives from the architects’ solution to fundamental challenges of the site: a dense and ambitious program, including the need for open, flexible gallery spaces of different heights and atmospheres, which had to be accommodated within a tight zoning envelope.

To arrive at a building that would address these conditions without becoming massive or airless, SANAA wound up assigning key programmatic elements to a series of levels (boxes), stacked those boxes according to the anticipated needs and circulation patterns of the building’s users, then drew each level away from the others laterally to the north, south, east, or west.

This approach resulted in cantilevers and setbacks that give the building’s exterior a unique dynamism and motion, while making a structure that is at the same time elegant and cohesive in formal terms. The shifted-box approach also yields open, fluid internal spaces that are neutral but unique at each level.

The building’s rough mesh exterior echoes the somewhat rough-edged neighborhood in which it is situated (which was once known as Skid Row). That corner of the Lower East Side is now a pivotal geographic, cultural, and artistic intersection—and the New Museum of Contemporary Art is well placed to contribute toward helping lead the much-heralded revitalization of the area.

Dallas Center for the Performing Arts
The city of Dallas is nearing completion on the Center for the Performing Arts Dee and Charles Wyly Theatre—an 80,300-square-foot multiform theater facility. Co-designed by Pritzker Prize-winning architect Rem Koolhaas and Joshua Prince-Ramus, the theater is part of a multi-venue center for music, opera, theater, and dance opening in 2009 that is being called the most significant performing arts complex to be built since Lincoln Center in New York.

Echoing the form of the New Museum of Contemporary Art, the Wyly Theatre is both aluminum-clad and organized in a “stacked” manner. The innovative 12-story design completely rethinks the traditional form of theater. Unlike a typical theater, where support spaces wrap around the stage house, the architects have placed these spaces either above or below the auditorium, enabling maximum interaction and flexibility of performance space and seating.

A second part of the complex—the Winspear Opera House—is also now under construction. The 2,200-seat opera house will provide a new home for the Dallas Opera, Texas Ballet Theater, traveling Broadway productions, and numerous other performing arts organizations that serve Dallas and the surrounding areas.

Designed by Foster and Partners under Pritzker Prize-winning architect Lord Norman Foster, the Opera House will feature an emormous aluminum Grand Portico radiating in all directions. The Grand Portico will provide shade over three acres of the adjoining Performance Park, creating new outdoor spaces for visitors to gather and relax. The canopy’s louvers will be arranged at fixed angles following the path of the sun, calculated to provide optimal shade for the outdoor spaces throughout the day.

Warren Civic Center
With the opening of the Warren Civic Center in November 2006—housing the new city hall and library—a master plan for the city of Warren, Mich., that was first drafted in 1963 came to fruition.
“I grew up here and watched Warren become a city,” said Mayor Mark Steenbergh. “Our citizens are hungry for a place of identity. This project brings that to the city.”

With a 2007 population of 135,000, Warren is the third-largest city in Michigan. But, according to a civic center design statement by Neumann/ Smith Architecture of Southfield, Mich., the city “is suburban in nature and lacked a downtown central core.”

According to the statement, the architectural firm was charged with designing a large, combined city building not only to replace the outdated existing city hall and library, but to address the broader idea of creating a new downtown:

“Although the city initially envisioned a 19th-century design solution, we recalled the city’s roots as an important industrial and research and development town whose great icon was the GM Tech Center. The resulting design concept is a modern response to the Tech Center. To achieve a complementary ‘bookend’ to the Vehicle Engineering Center, the tallest building on the GM campus, the city hall was stacked over the library to increase its height to four stories….A grand glass-walled atrium links the floors of the multi-storied building, serves as the indoor public space, and overlooks the new city square. A large cantilevered roof canopy extends out from the atrium over the plaza toward the city square. The structural columns and soffits create a modern formal front porch to the building and provide screening from the sun above.”

Although a number of traditional exterior materials were chosen to construct the civic center—including brick, stone, glass, and metal—they “are boldly composed to create a new image for the city of Warren,” according to Neumann/ Smith.

The center’s striking cantilevered canopy was fabricated from Alucobond Plus aluminum composite material (ACM) in a custom LCH Silver color and 4 mm thickness by Sobotec Ltd., of Hamilton, Ontario.

Measuring 140 feet at its widest point and 100 feet in length, the canopy is comprised of multiple geometrically shaped panels, according to Vlad Sobot, president of Sobotec. “This design is actually a bunch of canopies with a large one on top,” he said. “It looks like an airplane wing that is curved underneath and folds on top of the canopy.”

The project required the use of two 80-foot lifts to install the soffit and a 125-foot lift to install the fascia end. Erection of the canopy was completed on schedule in six weeks.

A total of 23,240 square feet of the silver Alucobond ACM was incorporated into the civic center. In addition to its use in the canopy, the material was used over the library entryway in a 32-foot by 25-foot canopy and in an oblong-shaped soffit measuring 45 feet long by 12 feet wide installed over the library’s book drop-off area. Alucobond Plus was also incorporated into column covers in the building’s glazing and as in-fill panels in the curtainwall of the parking structure.