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.

A few of us are in Ireland right now visiting with the suppliers who will be providing the windows, sliding doors, louvers, and glass for One Delisle. Thank you for the hospitality Flynn, Duggan Systems, and Carey Glass.

Below is a video showing a weather test that was done this morning. If any of you have been to the One Delisle Sales Gallery, you will probably recognize these sliding doors. They are fantastic.

Many of us probably don’t think about the supply chain that exists behind the products and services that we consume. But it is there and there are lots of smart people working "behind the scenes" to make everything happen.

FYI, the doors passed.

After my post about “the great balcony debate”, there was a bit of discussion on Twitter. Ken Wilcox then responded with a video talking about the mixed-use Timmerhuis building in Rotterdam designed by OMA. 

At the 1 minute mark there’s a clip of one of the residents opening a large set of sliding doors. Here’s a screenshot of what that looks like:

I did a bit of digging on the project and found this fact sheet. The sliding doors in the residential units measure 1.8m x 2.6m. They go from floor-to-ceiling (~8′-6″). The windows are also triple-glazed! (3 glass panes + 2 air chambers.)

I think this is a great way to open up a suite to the outdoors. It also looks like the glass balustrades sit inside, which keeps the building’s exterior envelope uninterrupted. Some of the other suites have large terraces where the building steps back.

In case you’re wondering, the construction costs for the entire project was about €100 million and the total gross floor area (including all of the non-residential uses) is about 45,000 m² (~484,200 sf). Unit rate seems reasonable given that triple-glazing is virtually unheard of in Toronto.

P.S. I am having some technical difficulties with Tumblr (my blogging platform) and Mailchimp (my email service provider). They both had problems and a few daily emails didn’t get sent out. Sorry about that. Hopefully it’s resolved now. If you missed the last couple of posts, you can read them online.