Since it opened in 2011, the $21.9 million VanDusen Botanical Garden Visitor Centre in Vancouver has been certified LEED Platinum and continues to garner awards.
The latest is the Metal Construction Association’s (MCA) 2013 award for Metal Roofing.
The award recognized the metal roofing material supplied by MCA member 3A Composites USA of Statesville, N.C.
The project employed Alucobond naturAL Aluminum Composite Material panels — a panel consisting of two 0.020 inch aluminum cover sheets thermobonded to a 4mm-thick polyethylene core.
“This Canadian project is one of our shining moments,” said Ben Branham, architectural marketing manager with 3A Composites.
“It was a natural for our submission to the MCA awards.”
A glulam wood structure and the panels were married to create the free-form design.
The roof covers more than 1,100 square metres and includes five petals that radiate from a central skylight.
The roof pitch ranges from two to 55 degrees, undulates significantly, slopes down to form a wall and ends at the ground.
MCA judges noted that “this is a beautifully executed building, with a roof crafted with exquisite detailing. The natural finish metal chosen for the building is easy to maintain.”
>>Perkins+Will Canada was the project architect and Ledcor Group of Companies was the contractor on behalf of client the Board of Parks and Recreation, Vancouver.
Rebecca McDiarmid, senior project manager with Ledcor and project manager for the centre notes that the original design called for a shingled sheet metal product.
“The roof edge had to be built from a durable material with a specific look to accentuate the roof lines that undulate in three dimensions,” she says.
The metal roof fabricator and installer for the project was >Keith Panel Systems Co., Ltd. (KPS) of North Vancouver.
“What we created is more than just a roof — it’s an architectural metal feature that became the signature of the building,” said Doug Dalzell, general manager and founder of KPS.
“The roof is the structure underneath, whereas Alucobond was chosen to fulfill the architectural statement. It can be shaped and formed like no other product. It’s virtually alive. KPS has completed nearly 3,000 projects with Alucobond.”
Fully recyclable, Alucobond also met the standards of the Living Building Challenge, a stringent measurement of sustainability in the built environment put forth by the International Living Future Institute.
Dalzell said that much of the heavy lifting occurred in the design development phase of the project, including the fabrication of a full-scale prototype nine metres in length.
“We chose a segment that represented the most radical aspects of the roof edge. It featured both positive and negative curves and we developed it to the point where we proved to ourselves that we could achieve the shape and form of the final design,” said Dalzell.
A review by Ledcor and Perkins+Will met with approval.
“From the first factory mock-up, it was clear that KPS was able to get Alucobond to create a much smoother roof line with fewer seams than what had been designed initially,” said McDiarmid.
“It’s amazing what they were able to do with the prefabricated metal panels.”
Dalzell said that the roughly 1,500 individual panels were fabricated using a combination of CAD software, 3-D digital tools, and KPS know-how.
“We developed a custom rotating coupler that allowed the nosing piece to go through positive and negative slopes in both plan and elevation so that the roof edge followed the curvature shown in the architectural design,” said Dalzell. “From an engineering and installation perspective, we’ve never seen it applied before.”
Sharp & Diamond Landscape Architecture Inc. designed the living roof plantings, in harmony with the aluminum art form.
Dalzell noted that KPS took special care to maintain precise detailing of the system during installation.
“Without this ability, any attempt to create these radical shapes and forms would have appeared very crude,” he said.
“Refined workmanship was an important contribution to the success of the architectural design.”