So, Herzog and de Meuron are building this trapezoidal-shaped tower in Paris right now.

It's 158m tall and about 40 storeys (which makes it comparable in height to One Delisle). It's extremely narrow in one direction (see above), and so from central Paris it is intended to be read as a kind of thin pencil tower. But when viewed in the east-west direction, you get the full width of its trapezoidal shape (see above, again).

Not surprisingly, this has been a highly contentious development -- which is why it was 15 years in the making. It is now under construction, though, and it is expected to be completed sometime in 2026. But this is likely to be the last tower in Paris for quite some time.

Partially because of this Triangle Tower, Paris has just decided to ban tall buildings in the city. The new height limit is now back to 37 meters (or 12 storeys), which is essentially the same height cap that was put in place in 1977 following completion of the Tour Montparnasse.

So this is seemingly how things work in Paris. Somebody builds a tall tower. People mostly hate it. And then the city bans tall buildings for a number of decades. The previous height cap was relaxed in 2010. (Also, for those of you who are wondering, La Défense, which is generally where Paris puts its tall buildings, is outside of the city limits.)

Regardless, I think there's no question that this new Triangle Tower is destined to become an iconic punctuation in the city's skyline. Which means that we're probably going to have to update our thinking. If Paris, today, is sometimes thought of as a city with two principal towers -- the Eiffel Tower and the "awful tower" -- it will soon be a city with three principal towers.

Perhaps the only question that remains is: Will people learn to love it like the Eiffel Tower or will it end up as another Tour Montparnasse?

Image: Herzog and de Meuron

New York architecture firm REX is working on a new office building in Washington DC that will incorporate a beautiful fluted glass facade. Here’s a rendering of what it is intended to look like:

Here’s what that looks like in plan (it’s a GIF that should show typical curtain wall vs. proposed fluted glass):

Here’s a photo of the 1:1 mockup:

And here’s a description from the architect:

The façade’s approximately nine hundred identical, insulated-glass panels—3.2 m tall by 1.5 m wide (11’-6” tall by 5’-0” wide)—are subtly curved to a 2.9 m (9’-6”) radius through a heat roller tempering process. The curve yields structural efficiency, which meets wind load requirements and enables a thinner monolithic outer lite than normal, providing greater transparency. 

Because of the curve’s inherent rigidity in compression, only the top and bottom edges of the panels are supported from the floor slabs, while the mullionless vertical edges are flush-glazed for a minimalist aesthetic that improves sight lines, while gaining usable floor area.

They are working in collaboration with Front Inc., which if you haven’t heard of, you should check out. They are a design/engineering consultancy that specializes in facades and building envelopes. They work with many of the big name starchitects. The developer of the project is Tishman Speyer.

It’s worth noting that part of the impetus for the fluted glass facade was to try and innovate within the confines of DC’s draconian zoning – which mandates that no building can be taller than 130 feet. Because of this, developers and architects are usually forced to build out to the allowable area, leaving little room for architectural variation. 

But in this case, the fluted glass removed the need for thick mullions and also allowed them to extend out beyond the lot area by 4 inches every 5 feet (the curves are considered “architectural features”). So this move has created both architectural variation and more rentable area.

It doesn’t appear that the building will have any operable windows, but other than that, I think it promises to be quite beautiful. What do you think?

All images from REX.