Earlier this week I stumbled upon this entertaining article from the Guardian talking about how expensive housing is in London. The author’s tongue-in-cheek suggestion was to setup a new miniature London in the middle of nowhere where everyone could flock for affordable housing, but where many of London’s attributes could be exported: “We can all refuse to wear socks and sell each other overpriced cocktails in jam jars.”

All joking aside, the article is yet another reminder that big global cities are expensive places to live. And in these cities, one of the most precious commodities is, quite simply, personal space. That’s why a garage in London can sell for £550,000 and why a 35 square foot storage cage in New York can sell for $75,000. 

But affordable housing is not the reason why people want to live in places like London and New York. If it were, they wouldn’t be coming. Instead, they come for lifestyle, wealth creation, and the dating market – among other things. However, at a certain point, usually when they form families and start to need/want more space, they start looking around.

Here’s an infographic via the Atlantic showing how relationship status impacts where people tend to live in London. The purple areas indicate an “above average concentration” of a particular relationship status. As you can see, single people tend to live in the core of the city, and when they get married, they move out to the periphery. Intuitively, this probably makes sense to you.

However, I’m always curious as to whether this trend happens more because of consumer preference (people don’t want to raise kids downtown) or because of economic necessity (they can’t afford anything beyond a shoe box apartment). Because if it is largely out of economic necessity (and the Guardian article would suggest it is), then we’re not creating the inclusive cities and neighborhoods that all city builders like to talk about.

So how do we get better at this?

In my view, and I’ve argued this before, the first step should be about improving supply. That is: get more housing built. And the way to start doing that is to make land available and improve the approvals process for new developments. In a recent McKinsey report, they referred to my first point as “unlocking land.”

“Land cost often is the single biggest factor in improving the economics of affordable housing development. It is not uncommon for land costs to exceed 40 percent of total property prices, and in some large cities, land can be as much as 80 percent of property cost.”

The reason this is important is because most big cities operate with massive supply deficits. There simply isn’t enough housing. And so if you can address that at a fundamental level, you can actually do a lot to start improving affordability.