Architects Continue to Impress with New Façade Techniques

By Ellen Rogers

Geometric shapes, curving façades, walls that move … today’s architects are designing distinctive, attention-grabbing façades. Bringing these structures to life often calls for close collaborations and custom products. Fortunately, the architectural glass and glazing industry is ready for the challenge, as many companies help to create these unique façades. So when their reps hear the question “Can you do this?” more and more often the
answer is yes. Here’s a look at just some of the recent “wow” innovations in architectural facades.

Geometric Shapes and Sizes

The new Calgary Central Library opened its doors to the public in November 2018, and represents the city’s biggest public investment since the 1988 Olympics. Designed by Snøhetta and DIALOG, the 240,000 square foot library features a unique, triple-glazed façade composed of a modular, hexagonal patterns that express the library’s goal to provide an inviting space for visitors.

The architects created aggregated variations on the hexagon form scattered across the building’s curved surface in alternating panels of fritted glass and occasional iridescent aluminum. The entire building volume is enclosed in the same pattern, allowing all sides to function as the building’s “front.”

Calgary-based façade contractor Ferguson Corp. engineered, manufactured, assembled and installed the entire vertical curtainwall and skylights on the project. The vertical wall consists of 462 unique unitized panels of white painted aluminum extrusion back sections with nominal dimensions of approximately 4 by 9 inches. The unitized panels were infilled with three different types of triple glazed, sealed units and three different colors of 4-mm (less than one inch) composite panels from the exterior, as well as 4-mm composite panels attached to the interior portion of the unitized panels. All products are placed around the building randomly to create the exterior architectural look. The glass was supplied by Vitro Architectural Glass and Oldcastle BuildingEnvelope® was the fabricator.

Some of the triple-glazed vision glass panels incorporated a ceramic frit on the exterior that had a “double dot” consisting of two different colors with an exact overlay. Ferguson project manager Alex Seegerer explained that the dot is white when viewed from the exterior and grey when viewed from the interior. This reduces the glare inside the building, while also allowing occupants to see outside.

“The geometry of the building created many challenges from an engineering, manufacturing and assembly point of view,” says Seegerer. “The layout of the entire envelope was done by 3-D-survey points. With anchor points to the floor slab only every 3000 mm, this created abnormally large anchor loads back to the structure. Special attention was required when embeds were placed and cast into the concrete slabs. [For the] composite panels on both the inside and outside of each unitized panel, we created a number of custom built tables [so we could] flip the oversized panels on the production line and be able to access both sides of the panel.”

Seegerer adds that there’s an area within the building open to two floors.

“In this space, Ferguson designed an interior solid steel fin 38-mm (about 1.5 inches) thick by 400-mm (about 16 inches) deep to support two floors of unitized panels. These steel fins acted as the structural support as well as sunshade baffles for the interior space,” he says.

In total, the project features 462 unique unitized panels. The average size was almost 10-feet wide by about 18-feet tall. The largest was about 10-feet wide by about 30-feet tall and weighed more than 3,500 pounds.

Fashion Forward Façade

Paris is one of the most fashionablecities in the world, in more ways than one. Even its architecture is worthy of the runway. The Tour Alto (or Alto Tower) is currently under construction, slated for completion in April 2020. Designed by the French firm IF Architects, the tower is a new, large-scale, business development located in the city’s financial district, “La Défense.” It features an innovative design characterized by a glass-scale façade and an unusual flare shape: alternating curved surfaces, concave, convex and flat parts. Permasteelisa is the project’s façade contractor, which will be a 492-foot high skyscraper accommodating retail spaces on the ground floors and nearly 538,000 square feet of high-class office space distributed in the 38 upper floors.

“At each floor, the edge beam shifts 12 cm outwards and, with it, the façade,” says Alex Cox, business development manager of the West Coast for Permasteelisa North America. “As a result, the surface area of each floor becomes larger and larger as the tower rises. At ground level the tower’s floor-plan is 700 square meters, while at the top it reaches 1,500 square meters.”

The development is also aiming to achieve the Building Research Establishment’s Building Research Establishment Environmental Assessment Method (BREEAM) Excellent Certification, and the use of a highly-efficient double-skin insulating façade will help contribute to this goal. The internal skin, which is being manufactured in Italy at the Permasteelisa Group headquarters, uses a double glass unit coated with ClimaGuard Premium by Guardian Glass, fabricated by Pietta Glass Working. The external skin, manufactured in Spain at Permasteelisa Espana, uses a laminated glass with the Sunguard HD Silver coating from Guardian Glass, fabricated by Vidres Viola.

Architects are designing projects like the Tour Alto more and more frequently, though such projects can also bring new challenges.

“Today we see a crop of talented architects using digital tools to generate complex 3-D forms for structure and skin. However, contract documents are still primarily 2-D drawings and written specifications,” says Cox. “There is a legal gap here that needs to be closed to improve efficiency in the architecture, engineering and construction trades. Also, the client’s cost estimation for such projects is often based on legacy information from simpler, more traditional designs, and there is ‘sticker shock’ experienced when the work is put out to bid.”

Window Wall High Rises

The curving elliptical that’s the new JW Marriott in Nashville has a secret: its glassy façade isn’t curtainwall. Atlanta-based firm Smallwood, Reynolds, Stewart, Stewart (SRSS) was the architect of record, while Arquitectonica served as a design consultant. The team took the 33-story hotel’s design in a unique direction and chose to use window wall instead of curtainwall. The firm worked closely with YKK AP North America to develop a custom
system that would be used to create the highrise hotel’s curving façade.

Project architect Mark Valliere explained there were three goals for the project.

“With an opportunity to work on a 117 meter tall tower adjacent to the newest, and perhaps most prominent, convention center in the southeastern U.S.—Music City Center—we had to be careful,” says Valliere, explaining three goals were established for the project. “First, create an iconic tower on the Nashville horizon. Second, complement the aesthetic of the Music City Center within the context of the SOBRO district. Third, create a visual
gateway at the confluence of Demonbreun Street and 8th Avenue, demarking
the city from the West.”

He explains that the curves and elliptical nature were a result of wanting to do something a little different, along with using window wall in an application where curtainwall customarily would be used.

“Inspiration for the design was taken from the subtle curves of the Cumberland River as it meanders through the city, mimicked by the adjacent Music City Center. The tower’s elliptical form rises an additional 31 floors beyond the two-story podium and—visible from virtually every vantage point in the city—glistens along every facet of the curved structure.”

There were challenges. For one, the glass itself isn’t curved. To create the
tight, elliptical nature of the façade, the window wall was segmented. “The skin of the tower was clad in a highly efficient low-E reflecting glass window wall system. This created a faceted appearance that reflected light uniquely from panel to panel, resulting in a dynamic, evolving appearance.”

The window wall wraps around concrete on one side of the building. “To maintain the monolithic identity of the tower, matching reflective spandrel glass dovetailed with vision glass to screen a large portion of the structure’s core. This deftly concealed large concrete shear walls that otherwise would have been exposed.”

Meeting energy codes with floor-to-floor and wall-to-wall glass can be challenging, and these considerations made the glass selection extremely important. The podium portion features Viracon 1-inch insulating glass units (IGU) constructed with VE 1-2M. The tower features a 1-inch IGU with VRE 1-38 with 44 percent exterior reflectance. Quarter-inch VRE 1-38 was used at the roof. Viracon also supplied the opaque glass used in the spandrel areas. Custom Enclosure Systems (CES), of Cartersville, Ga., was the contract glazier.

Barry Taraczkozy, general manager of CES says his company’s two main
components of the project were the podium curtainwall glazed with Viracon’s VE1-2M equaling 39,050 square feet and the tower window wall totaling 152,065 square feet, which was pre-glazed in the CES manufacturing facility with Viracon’s VRE1-38. He says both portions were equally challenging.

“The podium serpentine curtainwall layout gives a very fluid rolling appearance. The tower elliptical window wall wrap is epic within itself utilizing multiple custom mullion configurations to obtain the plan radius,” he says. “The pre-glazed window wall units ranged from 9 feet tall on typical floors to nearly 15-feet tall on the upper floors. [Our] installation schedule on the window wall was five days per floor, consisting of 98 pre-glazed panels per floor.”

He continues, “As if the elliptical layout wasn’t enough, the elevator shear wall running the entire height of the tower had to be glazed from the exterior of the building with swing stages. Rigging the upper floor unusually tall pre-glazed window wall panels presented a challenge maneuvering around concrete beams and cantilevering over parapets just to set them in place.”

Shimmering Walls

Whether it’s dubbed kinetic or dynamic, architects are increasingly designing facades with movement. California Sheet Metal of El Cajon, Calif., has worked on a number of “shimmering” or “sequined” facades. One example is the Westfield UTC shopping center in La Jolla, Calif. Designed by HKS Architects Inc., the center features more than 3,200 panels fabricated and installed by California Sheet Metal. The panels were 3-D laser scanned to facilitate precise design and layout of concrete embeds and the subframe.

This project features hundreds of light interference, colored stainless steel panels showcasing the entryway to Westfield UTC in La Jolla. The panels are attached using two stainless steel spindles as hinge points at the top of each sequin square. According to Scott Hollingsworth, business development manager with California Sheet Metal, this allows the panels to pivot with the wind and helps create the shimmer effect. The special etched steel was sourced from British metal finishers Rimex.

Hollingsworth says the use of more imagery in perforated metal applications is increasing. In these cases, it gives the project more texture, he explains, adding that when backlit it creates a whole new, nearly 3-D look. It’s these fabrication advances that drive architects to create new visual displays.

“3-D technology and software has allowed architects to get very creative. They’ve come up with something new to keep people’s attention, so they don’t lose interest,” he says. “We build what architects dream up and often it starts with a drawing on a bar napkin and it works its way into something that can be built and with satisfying results.”

Hollingsworth adds of these designs, “What makes it attractive … it’s ornamental metal artwork. It’s the cool factor and catches the onlooker’s attention.”

Ellen Rogers is the editor of USGlass magazine. Follow her on Twitter @
USGlass and like USGlass on Facebook to receive updates.

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