July 22, 2022: Normally, when a pre-existing structure is removed for a new development, especially in downtown Toronto, all remnants of the former structure are removed, the site backfilled as required, and new shoring and excavation are done to the perimeter lot lines.
At 400 King, it looks like the basement walls from the former MEC building are to be retained and incorporated into the new building, with shoring and excavation to take place within the perimeter of the existing walls. Tie backs have been installed all the way around in the existing basement walls. Probably helps that the former MEC building was basically lot line to lot line in the first place.
Photos showing the tie backs, the tie back machine sitting in the south-east corner of the former basement, and in the final photo, a worker is cutting off the protruding stubs of the most recently installed tie backs.
I thought this was a giant piece of public art on the backside of King Charlotte, not unlike the Sam record signs, and it took me much longer than I'd like to admit to see otherwise .... and I liked it!!
September 11, 2022 - Photos from Friday afternoon. Staging platform completed and in use, and a general view of the excavation - including some left over foundations from a building previously on the site - possibly from prior to its most recent iteration as the Mountain Equipment Coop store.