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J UNE 2018 | 67 Canada's Diversity Gardens – Assiniboine Park Conservancy RENDERINGS COURTESY ASSINIBOINE PARK CONSERVANCY Canada's Diversity Gardens – Assiniboine Park Conservancy by STACEY MCLACHLAN C reating a subtropical environ- ment in the middle of Winnipeg is no easy feat, but the talented team behind a new horticultural attraction at Assiniboine Park is working hard to add a little piece of paradise to the prairies. This stunning new architecture and landscape project is the third phase in a whole-house revamp of the park, fol- lowing redevelopment of the zoo and the addition of a new children's play- ground, restaurant, and event venue, and other improvements completed over the past decade. Construction has already begun on the brand new Canada's Diversity Gardens – intended for LEED Silver certification – with the goal to open to the public in 2020. "It's a celebration of people and nature," says Gerald Dieleman, project director of Canada's Diversity Gardens. Intended to celebrate cultural and botanical diver- sity via its architectural design and programming, a conservatory-like build- ing at the heart of Canada's Diversity Gardens (known as "The Leaf") will be a roughly 90,000-square-foot of space made of two biomes filled with sub- tropical and Mediterranean plantings. Doug Corbett, principal of Corbett Architecture and executive architect on the Assiniboine Park Conservancy, ran Integrated Design Process con- cept sessions to help the project team develop a clear goal: "Our mandate was to create a building with 'modern pur- pose', and one that would be iconic to Winnipeg. We didn't want this to be your traditional Victorian conserva- tory where you maybe visit a couple times a year, walk around, and never come back," says Corbett. The architecture and development team travelled around the world to find inspiration, and expanded the roster of consultants and contractors to include international experts; out of all this research and discussion came a vision for a light and airy modern design that blurs the line between inside and out. "For the biomes, we wanted to eliminate as much visual material as possible," says Lee McCormick, manag- ing principal for Architecture49. "It's like transporting yourself to a differ- ent place, and being part of nature." Eliminating visual blocks will also maximize the natural lighting for thou- sands of different varieties of plants on display inside. The team's desire for long spans and a transparent envelope resulted in the selection of a tensioned cable net roof clad with ethylene tetrafluoroethylene (ETFE) cushions. Pumped full of air, the EFTE looks like a series of translu- cent pillows held in place by a cable net. Of course, this unique design has its challenges. "Because of the long spans, the cables need to be preten- sioned with very high forces," says Renee MacKay-Lyons, project man- ager at Blackwell. "These forces need to make their way into the foundations, resulting in highly stressed members throughout the building." Besides the cables, a unique struc- tural element called the diagrid helps to provide support for the ETFE roof. "It's almost like a circus tent," explains Mitch Hall, principal at KPMB Architects. "The diagrid acts as a cen- tral anchor point." The diagrid also acts to conceal the essential mechanical and electrical systems – though pas- sive design means that overall, there actually isn't much to hide. "Primarily the goal was to provide the natural environment for each respective biome with as little mechanical intervention as possible," says Bryan Lord, mechani- cal consultant with Integral Group. Integral joined up with Transsolar to develop a model of both the Winnipeg seasonal conditions and tar- get space conditions. "Utilizing radiant heating from the sun and natural ven- tilation with actuated dampers, we found that for a vast majority of the year we can keep the biomes' ambi- ent temperatures equivalent to their native ranges," says Lord. "We're implementing an air inlet system sur- rounding the perimeter of the biomes with underground earth ducts to bring fresh air into the spaces." A natural exhaust system at the top of the diagrid maintains temperatures and will keep humidity at desirable levels for most of the year; root heating systems will help maintain healthy trees along with humidification misting systems to sup- plement the biomes when required. Esthetically, the steel diagrid also provides a contrast to the soft, green landscapes, while a waterfall cascades adjacent to the structure, adding an element of movement and fluctuation. "The highlight of this project from my perspective will be the skywalk that wraps around a 60-foot-tall waterfall in the subtropical biome," says Michael Peters, senior project manager for Bird Construction. "The mist of the water- fall together with the fog system will make you feel like you are deep in a sub-tropical climate." LOCATION Assiniboine Park, Winnipeg, Manitoba OWNER/DEVELOPER Assiniboine Park Conservancy EXECUTIVE ARCHITECT Corbett Architecture ARCHITECTS OF RECORD Architecture 49 / KPMB Architects GENERAL CONTRACTOR Bird Construction STRUCTURAL CONSULTANT Blackwell MECHANICAL CONSULTANT Integral Group/Transsolar ELECTRICAL CONSULTANT SMS Engineering LANDSCAPE CONSULTANT HTFC Planning & Design CIVIL/GEOTECHNICAL CONSULTANT KGS Group INDIGENOUS DESIGN CONSULTANTS David and Cheyenne Thomas TOTAL SIZE 90,790 square feet (building) TOTAL PROJECT COST $75 million (approximately)

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