It's an exciting time for structural engineering in Toronto. Earlier today, we talked about the hybrid exoskeleton structural system that will be used at The One, and now we look at another project pushing the limits of structural engineering; Amexon Development Corporation's Residences of 488 University Avenue. Designed by Core Architects (who are also working with Foster + Partners on the aforementioned The One) along with Sigmund Soudack & Associates engineers, the project is adding 37 new residential floors above an existing 18-storey, 1968-built office building.

Residences of 488 University viewed from the southeast, image by Forum contributor Red Mars

The project got underway in 2015 with the removal of the office building's original mid-Century exterior details, clearing the way for the installation of an exterior bracing system designed to independently carry the load of the new levels around the office tower and to foundations below grade. This bracing system has been sealed off by new curtainwall glazing, and capped with a tabletop transfer slab from which the new residential levels have begun to rise.

Residences of 488 University viewed from the southeast, image by Forum contributor Towered

Above, the base of the steel structure supporting the transfer slab marks the former roofline of the office tower prior to the start of work. While the existing office tower and structural support system were both constructed in steel, the large transfer slab and the new levels above are being formed with reinforced concrete. A closer look below reveals that crews are now forming the 20th and 21st floors, the first two above the transfer slab. With these levels much more slender than the office floorplate below, the residential tower's north and south stepbacks have become apparent.

Residential levels rising at 488 University, image by Forum contributor Towered

The forming of the residential levels marks an important milestone for the project, which had to wait through much of 2017 for the crucial and complicated tabletop structural work. Residential levels will soon rise at a much faster rate, as the forming and repeating typical layouts will put workers into a rhythm. Changes to the floorplates will be relatively minimal as the tower rises, meaning we should see 488 University reach its final 207-metre height before the end of 2018.

Residences of 488 University, image courtesy of Amexon

Additional information and many renderings of the development can be found in our database file, linked below. Want to get involved in the discussion? Check out the associated Forum threads, or leave a comment in the space provided at the bottom of this page.