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The building boom that has been reshaping Toronto since the mid-2000s continues unabated, and is getting more exciting with construction of projects that will overtake First Canadian Place as Canada's tallest building, a title it has held since 1975. The first building set to overtake the reigning monarch of Canadian skyscrapers is well under construction at the intersection of Yonge and Bloor, as Mizrahi Developments' The One slowly ascends and reveals more of its impressive structural engineering in the process.
Designed by UK-based architects Foster + Partners with Toronto's Core Architects, The One has consistently ranked among our top three most-visited project database pages and Forum threads as interest in the project's immense height and unique design drive a rapt audience. The buzz over the building has grown this year, with an early 2021 application for additional height that would take the tower from the approved 85 storeys to a new 94-storey, 338.3-metre height. The current approved 308.6-metre height would already place The One over ten metres taller than First Canadian Place, while the proposed height increase would allow The One to retain its title as Canada's tallest, even after competing Toronto supertall projects like the 312-metre SkyTower at Pinnacle One Yonge rise into the mix.
After a pause in construction as the project awaited its above-ground permits, work has been heating up on the site since mid-2020. The star attraction has been the rise of the initial few floors in the building's hybrid exoskeleton system, which is supported by eight 40-tonne steel-core, concrete-encased supercolumns, which along with a lattice of steel beams and canted columns, now extend up to the seventh floor. Meanwhile, concrete-formed podium volumes have taken shape to the west and south of the tower.
At the base of the tower, much of the future flagship 12-metre-high retail space is now visible to passersby. With a column-free floor designed for a flagship tenant, its layout dictates the complex structural work required for the floors above: the tower's main elevator core must be 'floated' above, with an extra-thick slab to support it. The elevator pit will be built on the fifth floor, supported by a pad that will be poured within a grid of steel beams that currently surround the central crane.
Before that important structural element is built, the more levels must first be formed below. When we last checked in on construction at the start of March, the third floor slab above the cavernous retail space was in place and assembly of the steel skeleton had etched out future restaurant and event spaces on levels three and four.
Floor numbering for the tower include the podium levels, so accounting for the extra-high retail space, the current forming activity represents the slab of the fourth floor. Forms and rebar bundles were placed earlier in the month in preparation for the pour, which was carried out on Monday.
The initial tower floor-plates are being poured with missing notches from the corners. While the central supercolumns extend through the concrete slabs, the exoskeleton's diagonal "hanger" braces will come afterwards along with the missing slab corners once more floors are in place.
Another on-site event is the ongoing relocation of a tower crane at the south side of the tower, which has been moved to a new position atop the now structurally-complete southern podium. The crane was disassembled earlier this month, and over this past weekend, reassembly began in the new location.
The relocation will allow the yellow crane to rise along the tower's exterior—in a similar configuration to what was seen a few years ago at the L Tower site at Yonge and Front—as The One begins to make its mark on the Bloor-Yorkville skyline.
You can learn more from our Database file for the project, linked below. If you'd like to, you can join in on the conversation in the associated Project Forum thread, or leave a comment in the space provided on this page.
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