Monthly Archives: October 2011

The Sensible City — Hyper-Density for Better Living

I recently read a book called The Triumph of the City. In it Edward Glaeser describes how life is better in cities, and the more dense they are, the better. The prime example of this is New York, and specifically Manhattan, with a population density of over 70,000 people per square mile.

Manhattan is more energy efficient, offers higher wages, a better life expectancy, and is generally superior to most other locations by many measures. Whether your passion is sports, fine arts, theater, or education, Manhattan has you covered. The social scene can’t be beat, and the opportunity to find kindred souls, for friendship or romance, is unparallelled. 

One of the problems of Manhattan is the incredible cost of real estate, and that can be attributed to supply and demand. Glaesar describes how new building in Manhattan has slowed, driving up the cost of housing. 

I tried a thought experiment: consider a building that is sixty stories tall, and two hundred feet on a side. Such a building can contain roughly 30 apartments per floor, at a thousand square feet each. With sixty floors, that’s 1800 apartments. Let’s assume that the average apartment holds two people (500 square feet per person seems generaous in Manhattan, but I wasn’t able to find any statistics), for a total of 3600 people. Manhattan has a population of about 1.6 million people, so that means we need roughly 450 of these buildings. Consider the following graphic:


I left Central Park in for scale. Each pixel in that impage is roughly 100 feet on a side, so each of the white dots (2px square) is one of these buildings. They’re offset and spaced out, so everyone can have a view of something. This doesn’t take into account commercial and office space. I wasn’t able to find a comparison of non-residential to residential square footage in Manhattan, but I do know that a typical office building includes roughly 300 square feet per employee. So let’s assume that between commercial and office space, each of those people in Manhattan needs an additional 500 square feet. Office buildings, malls, and factories can be placed in larger buildings, so let’s make them twice as big on a side. That means we’ll only need about 110 commercial buildings



Now what are the advantages?

First is even better fuel efficiency. Even laid out as it is now, only two subway lines (with express and cross connects) woud be mad