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Standing tall on the southwest corner of Bloor and Yonge streets in Downtown Toronto, One Bloor West has claimed 'supertall' status since June 24, 2025 when two I-beams were riveted to the top floor of the 85-storey tower. The height has not changed of the Tridel-helmed project since then despite a lot going on at the construction site of Toronto — and Canada’s — tallest building so far. Designed by Foster + Partners and Core Architects with a unique structural system that supports the building through 8 'megacolumns', 2 per side, the building initially rises with cruciform shaped floor-plates, with slabs created within the extents of those columns. Ultimately, though, the tower is square in shape, so the corner slabs, which are hung on brackets held by the central cruciform section, have to be built afterwards, and this is where much of the catching up has been going on since.
As the floors have been going up, weather protection forms have been affixed to the sides of the building, in two places in fact: the forms at the top have been painted blue, while many floors further down the building, black forms have been in place for cladding installation. Both sections can be seen in the image above from August 29, 2025, with the black cladding installation 'RCS' forms (Rail Climbing System) covering floors in the 60-storeys range. A close-up southeast-facing view of the RCS, below, shows the west side RCS trailing a floor below the north screen. Below the RCS the reflective curtainwall in installed along with the building’s distinctive annodized aluminum framing over the megacolumns and brackets.
From this more recent northeastward view, the west and south screens of the RCS have climbed to roughly the 68th floor. The tower’s 18-storey residential groupings can be seen, separated by two-storey mechanical floors. With the corner slabs now complete, the blue corner scaffolds have been removed, with a few blue panels remaining at the centre of the west elevation. Meanwhile, the crane has been raised with an additional mast section to prepare for work on the building's crown.
Looking up along the south elevation, a crew member can be seen around the 83rd floor fastening tie brackets that affix the crane to the tower. The operation allowed the cranes additional height. At the same time, the construction hoists that run up the south side of the building now rise as high as the 85th floor.
Looking straight down, this drone image captures the completed rooftop slab. Along each elevation are pairs of steel girders (two of which pushed the building past the 300m threshold), will be extended soon. The rooftop deck itself is staged with tower crane brackets and other materials around the central elevator core.
This southwest-facing drone view better captures the final sections of levels.
What remains to be built of the structure now is the crown within which the building's TMD, or Tuned Mass Damper, will be held. A TMD, in this case a hugely heavy, multi-layered metal weight suspended from the top of the structure, resists the forces of wind on a building by moving in the opposite direction, counteracting sway and keeping the building pleasant to be in. The finished look is depicted in the rendering below, extending the megacolumns like outriggers from a chamber that will rise above the elevator core. Structural work should begin for this section soon.
When complete, One Bloor West will stand 308.6m tall with 476 condominium suites and a 139-room hotel, along with other retail at its base.
UrbanToronto will continue to follow progress on this development, but in the meantime, you can learn more about it from our Database file, linked below. If you'd like, 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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