Population density is one of the most interesting topics in urbanism because
it’s so central to what cities are. In this video we’re going to take a tour of density
in the U.S. and Canada from semi-rural suburbs to ultra-dense downtowns to see just how much
density varies between neighbourhoods and what different levels of density look like.
A population density of zero means that no one lives there. This census tract in Madison,
Wisconsin has a density of zero because it’s a frickin’ lake! A density of zero doesn’t
always mean the area is empty though. There might be commercial or industrial
buildings like here in Edmonton, Alberta or an airport like here in Arlington, Virginia.
Population density counts people, not buildings, and specifically it counts
people where they live rather than where they work. That’s why population density is useful
but not perfect for judging things like transit ridership potential. It’s also why residential
neighbourhoods have a higher density than a city as a whole — the city includes lots
of other important amenities like offices, parks, and stores that don’t add to density.
A population density of 500 people per square kilometre for a residential neighbourhood is very
low. This census tract in a suburb of Montreal is about that density but only because half the space
is taken by a golf course. This residential neighbourhood on the outskirts of Fort Myers,
Florida is a better representation of this density; it straddles the line between
suburban and rural with some houses here not being able to see their neighbours. This area
looks like it’s waiting to be filled in with more homes. Another example of 500 people per square
kilometre is the mansions of Atherton, a wealthy suburb in the San Francisco Bay Area where the
average home will run you about $10 million. This city prides itself on its “semi-rural character”,
which it enforces by banning denser, more affordable types of housing from existing there.
1,000 people per square kilometre is on the low end of density for typical suburbia,
like this census tract in Wyoming, and by Wyoming we mean Wyoming, Ohio, a suburb of Cincinnati,
which has generally large homes on large lots but there are some more modest homes too.
Another example of 1,000 people per square kilometre is here in Goldsboro,
North Carolina where the houses aren’t massive but the yards are
big and there’s a lot of empty space and that can dilute density really quickly.
Doubling the density to 2,000 people per square kilometre gets us closer to a typical North
American suburb, like this neighbourhood of Edmonton built after World War II.
Most people live in detached homes that are modestly sized and reasonably close together
with prominent although not enormous front yards. Each house here takes up a bit more space than it
looks because of deeper lots with garages in the back. There are a few places where lots were split
to build thinner but taller detached homes, and if that continues it could add a decent
amount of housing to the neighbourhood. There are also a few apartments or row houses around
too but they’re very suburban in form, with lots of space dedicated to grass and parking. A similar
density of 2,000 people per square kilometre can be seen in this northern suburb of Seattle.
Another doubling to 4,000 people per square kilometre starts to become pretty dense by
suburban standards, like this neighborhood in Ajax, a suburb of Toronto, or here in Santa Clara,
California, in the San Francisco Bay Area, where single-family homes are built closer together
with less space in the front and especially back yard than we saw at the lower levels of density.
Another model for more dense suburbia can be seen in this South Shore suburb
of Montreal where the detached homes still have pretty spacious backyards — you know
you’re in suburban Quebec when nearly every single detached house has a pool in the
backyard — but the density is brought up by the abundant duplexes and small apartment buildings
that house almost half of the families who live here. For both cultural and economic reasons,
Quebec has never been quite as obsessed with single-family homes as English North America.
The result is more density and housing diversity even in otherwise pretty suburban contexts.
Doubling the density again to 8,000 people per square kilometre takes us
past suburban density to what we’d call the lower end of urban density,
like this neighbourhood of two- and three-storey row houses in Philadelphia where the density is
pulled up by the row houses but pulled down by the pretty large yards that a lot of them have.
Another example of this density is this census tract in the Kitsilano neighbourhood of Vancouver
where we have the densest configurations of detached homes that we’ve seen so far
combined with some pretty compactly-built low-rise apartments sprinkled around.
Doubling to 16,000 people per square kilometre gets us to what we’d call urban medium-density.
Here in Canada the undisputed king of this type of neighbourhood is Montreal, whose older
neighbourhoods of two, three, and sometimes four-storey walk-up apartments are one of
our favourite topics on this channel. They reach this density because they cover most of their lot,
without the larger lawns of the Philadelphia example, and because the neighbourhood is almost
entirely apartments. This part of Minneapolis shows the same average density with more of
a mix of housing. Because there are detached houses here and everything is a bit less compact,
the apartments have to go a bit higher (mostly mid-rise with 6 or 7 storeys)
to match the density of the consistently compact and low-rise Montreal neighbourhood.
Another eclectic neighbourhood that reaches urban medium-density is here in Long Beach,
California, which has detached houses, small high-rises, and everything in between.
32,000 people per square kilometre is what we’re going to call upper-medium-density,
although we wouldn’t fault you for calling it high density. This is the kind of density
you might achieve with some slim high-rises mixed with townhouses like here in Toronto;
some wider but pretty spaced-out towers like here in Coney Island,
New York; or this pretty tight mix of low- and mid-rise in Brooklyn, New York.
Doubling to 64,000 people per square kilometre puts us solidly in the realm of high density,
like this part of Manhattan with a tightly-built mixture of mid-rises and high-rises,
this 12-storey residential conversion of an old warehouse in Toronto that we’d describe
as a short, boxy high-rise, and this more varied development in Vancouver that goes
taller (30 storeys at its peak) but has more variation and open space.
Finally, 128,000 people per square kilometre and above brings us to “very high” density.
All of our examples here are from New York City,
and most of them are very tall developments that try to incorporate parkland or open space without
going as far as having so much empty space that the density is substantially diluted,
like we saw with the Coney Island example with its parks and parking lots.
But once we get to the absolute highest densities — approaching 200,000
or even 300,000 people per square kilometre — we increasingly see tall towers that cover
almost all of their lot. The very densest census block group in the United States is a part of the
Financial District in Lower Manhattan where two skyscrapers (57 storeys and 37 storeys) go right
up to the street and together achieve an insane density of 282,000 people per square kilometre.
Based on this tour of population density in the U.S. and Canada, from semi-rural suburbs to the
ultra-dense residential skyscrapers of Manhattan, we have two main takeaways about density. The
first is that density can vary quite a bit without necessarily feeling that different. We live in a
medium-density neighbourhood in Montreal and one of the areas we looked at in Brooklyn feels pretty
similar despite having double the density. The basic development pattern is the same,
the heights just go one or two storeys higher on average. And the suburb of Montreal whose
abundant duplexes and small apartment buildings double its density compared to a more typical
North American suburb still feels fundamentally suburban with its open space and abundant parking.
The second main observation about density is that building height is one important factor in but
not the only factor. At almost any density level there’s a trade-off you can make between
building taller and having more open space and building shorter but covering more of the lot.
Personally we usually prefer a more traditional compact pattern where buildings use more of the
lot and come closer to the street but it’s definitely a matter of preference and taste.
What some consider cozy, others consider claustrophobic. Another trade-off is consistency.
Like we saw comparing Montreal and Minneapolis, apartments don’t have to be as high to achieve
a certain density if the whole neighbourhood is apartments. If the apartments are mixed in with
lower density housing like detached homes, they need to go a bit taller to bring up the average.
And finally, we should mention that population density isn’t entirely about buildings.
Demographic and economic factors matter too, so places with high housing costs or low incomes
will often have population densities higher than you’d expect from just looking at the buildings.
None of the numbers we’ve provided here should be taken as exact,
but they do give a pretty good ballpark picture of what different levels of density look like.
Thanks for watching through to the end of the video.
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