Architect: Stanford Downey Architects Inc.
Engineer: Halcrow Yolles
Contractor: Ellis Don Corporation
Reinforcing Bar Fabricator: Harris Rebar, Stoney Creek, Ontario
Total Project Size: 515,000 sq ft
Award: 2008 CRSI Design Award Winner
One King West is a 51-story hotel and condominium tower located in downtown Toronto that encompasses part of the historic 16-story Dominion Bank Building. With a height-to-width ratio in excess of 13:1, it is purported to be one of the world’s most slender buildings. The tower rises 620 feet above its base and is 47 feet wide at its broadest. Floor plates are generally lens shaped in plan with overall dimensions of 47 by 167 feet. The tower comprises a gross construction area of 515,000 square feet and contains 576 residential suites and 102 parking spaces.
The heritage building features an elaborate exterior façade, a large and ornate banking hall, and a massive bank vault. The client determined that this building and all of its prominent features be retained intact within the new development, creating a significant challenge to designers and constructors as a number of the tower’s vertical elements needed to be installed inconspicuously within the existing building. Due to its slender vertical aspect ratio as well as its elongated floor plan, the tower required a robust lateral system. The overriding serviceability issues relate to inter-story drift and top floor accelerations.
Reinforced concrete was seen as the only viable option for the structure for a number of reasons. Given the slenderness of the tower, the lateral system needed to be exceedingly stiff. The reinforced concrete walls and slabs provide effective fire rating and sound/acoustics insulation between units. The low, flat plate slab depth reduces the overall height of the building, thereby reducing cladding costs and obviating the need for ceilings. In addition, reinforced concrete was used effectively to create the rooftop tank used as a “sloshing” liquid damper.