The first thing that stands out to me in this European office vacancy rate chart from Savills is the difference between Paris-La Défense (~15%) and Paris-CBD (2%).

For those of you who maybe aren't familiar, La Défense is the largest purpose-built business district in Europe. It houses upwards of 40 million square feet of office space and covers about 1,400 acres. It's also more or less where Paris decided to allow and put tall buildings. Though, it is about 3 km west of the city limits.

The Paris-CBD, on the other hand, is within the city limits and I'm assuming it refers to the quartier central des affaires (QCA). But regardless of the exact boundary definitions, what we are comparing here is a purpose-built business district to an older supply-constrained central one. And clearly there are, right now, meaningful differences in demand for the offices in these two areas.

What's also interesting is that there's a meaningful difference in the rents. According to Reuters, office space in La Défense is on average about 50% cheaper than the QCA. This, to me, is a reminder that monofunctional urban areas tend to be less resilient over time. And that's why La Défense is actively working to add additional uses, such as more residential.

But it's not just about uses. The area will also need to contend with the fact that it has a vastly different kind of built form; one that isn't fine-grained and walkable like the QCA. This matters.