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Shine On
Glass and Metal Combine to Create One Eye-Catching Museumz
by Ellen Rogers

Inspiration comes in many shapes and forms. Randall Stout of Randall Stout Architects Inc. in Los Angeles found his within the city of Edmonton, Alberta, Canada. Stout won an international competition to design the Art Gallery of Alberta (AGA). Many factors, particularly environmental conditions, had to be taken into account, as Stout sought to create a unique, curvilinear building. Glass and metal played a significant role in bringing the $86 million building to life; it features a 190-meter ribbon that references the forms of the North Saskatchewan River and Aurora Borealis.

“I visited Edmonton a lot during the competition phase, getting to know the city, the climate, the sense of community and particularly the place within the city where the building was to be located, Sir Winston Churchill Square, the ultimate festival and meeting place there,” says Stout. “I think those trips led to an understanding of the city and there were two major observations that helped evolve the design. One was that Edmonton’s urban grid is very orthogonal. Yet the North Saskatchewan river, as it moves through the city, has a curvilinear, sinewy shape that is untamed compared to the way we allow rivers to move through cities in the United States.” For example, he says Edmonton has the flood banks, as well as all the nature of the river in the open landscape. He found this to be an interesting juxtaposition.

“The second observation was there happened to be a parallel in the gallery’s own program that I thought reflected [the surroundings]. Unlike museums that show a vast amount of permanent holdings in an exhibit space and dedicate only a small amount to traveling exhibits, AGA takes the opposite approach with about 80 percent being traveling exhibitions and only about 20 percent being permanent,” says Stout. “So they needed the galleries to be neutral and flexible. They wanted the public space to have a real wow factor; thus there was a need for both neutral space as well as the celebratory space, which would be used to celebrate the life of the community.

“I thought about the urban grid and the rivers through the city and the programs’ needs and felt the building could respond in completely separate ways—it could have the language that would be much more pragmatic for all gallery spaces and then have a completely different language, which is this curvilinear form that could tie together the multiple floor levels and the multitude of public activity spaces.”

Material Matters
Material selection was a critical component when it came to the design, as Stout and the project team wanted to construct a building that would be durable.

“A 100-year building as they say,” says Stout. “We felt the metals would do that.”

The AGA features a combination of stainless steel and zinc, both of which have long life cycles.

“Plus, the installation mechanisms do not rely on caulking or other types of less durable joints, as the materials are all mechanically fastened. Everything about the installation is meant to be durable and lasting, particularly in the extreme climate of Alberta,” says Stout. “From an aesthetic perspective we also wanted the materials to complement one another, given the idea that there were both rectilinear and curving forms in a building. We did not want to use the identical material between the differing forms.” In this respect, the stainless steel was used on the curved forms and the zinc on box-like forms.

“This set up a nice relationship between the two materials,” says Stout, who adds that the materials also blend well with the surrounding architecture.

Acheson, Alberta-based Flynn Canada served as the project installer. On the metal side, they worked with A. Zahner Co. out of Kansas City.

“Flynn was involved with the design in the pre-construction phase, which included the multi-scope building envelope,” said Charles World, business development manager for Flynn.

The museum features a wide expanse of curtainwall on both the interior and exterior of the building. Kawneer’s 1600 curtainwall and 2000 skylight were used on the exterior of the building, while the 2250 IG (inside glazed) curtainwall was used at an interior frame. It also features the company’s Trifab® VG (VersaGlaze®) 450 framing system and 350 standard entrances.

While incorporating 37,000 square feet of the museum’s old facility, a concrete structure from the late 1960s, the new portions of the design used no straight angles, and provided a challenge for both design and installation.

“The complexity of the design, with sloped curtainwalls and the intersecting skylights required a great deal of coordination from every participant on the project at every phase,” says Wayne Brandt, Western Canada Regional sales manager, Kawneer North America.

Likewise, Stout notes that ten types of glass, supplied by Viracon, were used. These glass types included 1-inch insulating units that have a clear, heat-strengthened exterior lite with a low-E coating on the number-two surface and a ¼-inch thick interior lite; silkscreened 1-inch insulating units of the same make-up; non-insulating laminated glazing constructed with an Arctic Snow PVB interlayer; interior single glazing; 1-inch insulating spandrel glazing; tempered monolithic glazing (for areas such as glass guardrails, etc); non-insulating laminated glazing constructed with a clear PVB interlayer; fire-rated glass; 1 1/4-inch insulating units constructed with a low-E coating on the number-two surface on the exterior lite and an interior lite made of two layers of 1/4-inch clear glass with a clear PVB interlayer; and 1 1/4-inch insulating unit constructed with a tempered, clear lite with a low-E coating and 1/8-inch dot frit on the number-two surface, and an interior lite made with two layers of 1/4-inch clear glass and a clear PVB interlayer.

“Because the atrium has southern and western and even eastern exposures we used an IG with low-E glass and a dot ceramic frit and in some views you can’t even recognize there’s a frit,” says Stout. “It blocks about 50 percent of the heat gain.”

In addition, Bronco Industries Inc. in Kelowna, B.C., supplied the handrail glass; tempered sealed units around one of the stairs were supplied by Oldcastle BuildingEnvelope and fire-rated glass at the Education Entry stair was by Technical Glass Products.

“It was a huge challenge … how do we make a structural connection through the glazing without having the structure itself transmit the extreme temperatures from the outside to inside?”
—Randall Stout

All on Board
In order to ensure a successful team collaboration, Stout explains the AGA construction was carried through as a “construction manager (CM) at risk” project.

“This means you hire a CM during design phases and at the time when all contract numbers are put together and you’re ready to build the job, that entity becomes the general contractor (GC). However, they are contractually on board with the client early on,” explains Stout. “In this instance the owner hired the CM at risk, which was Ledcor, prior to the competition and they used that company to evaluate the constructability of the schemes and the cost projections during competition phase.

“So by the time we came on the GC was under contract as CM at risk. In that format what you’re allowed to do, rather than just wait until all the drawings are done, and go out and bid to the trades at once, is identify the high-risk aspects of the design and solicit specialty subcontractors with the skills and experience to pull it off,” says Stout. “Thus we solicited bids while still in the design phase for exterior metal, glazing and structural steel. In doing so we were able to talk to multiple bidders and get a scope price tied down relative to metal and glass. Once we had that identified, those entities started to act like design partners. We call it design assist since we’re not completing our detailing in isolation, but rather we are collaborating with the sub trade to finish detailing of the job.”

Working in such a manner, Stout says, can bring many benefits to the project.

“There’s a high level of confidence in the sub trade if they know their standard details are being used. If we deviate from those standard details they know exactly where those deviations occurred and they know where to spend more of their own engineering time developing shop drawings, etc.,” says Stout. “The other big thing it does for the client is it improves the warrantability of the scheme. When we ask for a long duration warranty to benefit the client, if the sub trades are on board and they’re comfortable with how the detailing of the project is being accomplished, then their comfort level in giving a healthy warranty is increased. I look at the whole delivery method as a win-win situation.”

Stout also notes that the entire project was designed as a 3-D model, from which all groups worked.

“All collaboration was based on the same computer database,” says Stout.

Seasonal Expectations
From a performance standpoint there were several considerations to take into account. Stout says one of the most significant was the climate extremes in Alberta.

“Because of the frigid, frigid cold winters, as well as the shoulder seasons (spring and fall) you get a high number of freeze-thaw cycles and within those cycles pretty extreme temperatures, particularly on the west façade of the building, which heats up with late afternoon sun,” says Stout. “Then at night the temperatures drop to sub-freezing.”

He explains that putting a thermal envelope around a box-type structure is relatively simple.

“Sometimes the curved forms of this building are a wall, sometimes a roof, or an exterior canopy … and so it was a huge challenge … how do we make a structural connection through the glazing without having the structure itself transmit the extreme temperatures from the outside to inside?” says Stout. “If the temperatures managed to migrate through the structural joints and glazing façade you would get condensation buildup on the structural seal and there would be all kinds of problems.”

To solve the problem Stout says they had to thermally isolate every structural penetration of the atrium.

“Every time a curvilinear piece moved in and out there were thermal isolation joints within every structural connection,” he says. “That was some tricky detailing and we used oak wood because it has extremely high strength from a compressibility standpoint and these joints were under a lot of compression. Plus, it also has good thermal properties.”

Sense of Wonderment
After three years of construction, the AGA was completed in 2010. Stout says having worked on the museum there’s a lot that stands out about the structure’s uniqueness. “First and foremost it accomplishes a special experience for the museum-goer. I can’t tell you how many times I’ve stood in the lobby watching the facial expressions of people who walk in and look up into the multiple levels of gallery access points and see this curvilinear piece that is something of a companion as they move up through space,” he says. “There’s often a sense of wonderment, almost a child-like reaction to something they’ve never seen before.”

He adds that the architecture, in a way, also contributes to the overall vision of the institution which is about service to the community and welcoming all levels of visitors. “The building, in some ways, has a gregarious personality,” Stout adds. “It’s message is to come in and see what’s going on with its unusual shape.”

Speaking from the installers perspective, World adds, “This is certainly the most dynamic design for a building in Edmonton. This museum space is a cultural contribution to the community and we hope that the building itself will set the bar for architecture in the city.”

Since its opening the AGA has received numerous awards and recognitions, including the Metal Construction Association 2010 President’s Award for Overall Excellence and the Canadian Institute of Steel Construction Alberta 2011 Architectural Award, among others.

Ellen Rogers is the editor of the Architects’ Guide to Glass & Metal (AGG) magazine. She can be reached at erogers@glass.com or follow her on Twitter @AGGmagazine and like AGG magazine on Facebook to receive updates.

Architects' Guide to Glass & Metal
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