Yesterday, February 28, 2025, the team installed the first piece of unitized curtain wall at One Delisle (on level two facing the outdoor amenity terrace and beside the indoor pool). Last year I was going around telling everyone that we would have glass up on the building in the first quarter of this year, and so I'm really glad that I was not made out to be a liar. Thanks team. This is a milestone date.

For those of you who maybe aren't familiar, there are two types of window systems that are commonly used in high-rise residential buildings. They are usually referred to as window wall and curtain wall. The former is more common in Toronto because it's, well, the cheapest; but there are curtain wall buildings other than One Delisle. Sometimes the same building might also use both systems. (In saying this, I'm specifically referring to the upper floors, because curtain wall is often used for ground-floor commercial spaces.)

The key difference is that window wall systems sit between floor slabs and get anchored at the sill and the head (the top of the slab on the bottom and the bottom of the slab on the top). Curtain wall systems, on the other hand, get anchored to the exterior slab edges and also "bypass" them. You can see that in the above photo. There are advantages and disadvantages to both systems, but generally speaking, curtain wall is viewed as higher quality, and the more expensive option.

In the case of One Delisle, we explored and were open to both options during the design process. But ultimately window wall just didn't seem like the right system to realize the unique geometries of this building. So we went with curtain wall, worked through a lengthy design-assist process with the subcontractor, built a bunch of mockups to make sure everything looked and worked well, and now it's being installed on site.

Level two is likely going to be the most challenging floor because of the double-height pool area. So I'll be sure to share more photos once it's all enclosed.

We've spoken before about One Delisle's fun slab edges. No two floors are the same. The tower is constantly changing as it transforms from a square at its base to a hexadecagon at its top (16-sided shape). But one part of each floor that does repeat is the core (the center of each floor plate that houses the elevators and other essential stuff). And so for this, the site team is now using something known as an automatic climbing system to "jump" the concrete forms between the floors. More specifically, we are using a Doka Super Climber SCP.

Here's what that looks like inside the core of the building right now:

At a high level, the way it works is pretty simple. The system has two levels of brackets that can anchor to the concrete core of the building, below the floor that is currently being poured. The concrete forms are then raised using hydraulics. And once that has happened, the lower brackets "climb" up the building and get reattached at a higher point. If this isn't clear in your mind, imagine Spiderman climbing up a tall shaft. His arms would represent the upper brackets and his legs would represent the lower brackets. Maybe this isn't helpful.

In any event, the point of this system is that it makes construction go faster. So now that the ACS is up and running, the team is looking to bring down our cycle time per floor. Hopefully you'll notice that the next time you go by One Delisle.

This morning I was on site at One Delisle with WZMH Architects (AOR) and Studio Gang (design architect). I aim to visit site at least once a week, but lately it's been more than that. What's exciting to see right now is that the geometry of the tower is starting to come through in the slab edges. (The architects also made sure to remind me today that they had to draw each and every one of these.) The above photos were taken from the level 2 retail terrace. We always imagined this space becoming an amazing restaurant overlooking Yonge Street -- but we'll see what happens.

Expect to see a lot more of these fun slab edges over the next few months.