DC Skyline. CC image from Ed Uthman.

DC’s lack of tall buildings is certainly one of it’s defining characteristics.  Given our human tendencies to be loss averse, to embrace the status quo, it shouldn’t be a surprise that changing such a characteristic can be shocking to some.

I’ve written on the height limit before, as have many others.  The most recent defense of the law comes from Kaid Benfield (both at the NRDC and Atlantic Cities). Kaid outlines some good qualitative reasons to embrace the limit – unfortunately, marred by some of the serious shortcomings and logical fallacies from his other arguments in support of the limit. I share Ryan Avent’s frustration with some of the manners of argument.

As an example, some of the arguments Kaid presents in favor of the height limit, and a brief response:

Actually, DC can grow under current law. In 1950, with the height restrictions fully in effect, the city’s population was 802,178. In 2011, its estimated population was 617,996. The truth is that we were a “shrinking city” until about a decade ago, and we are nowhere near full capacity today.

It is misleading to call DC a ‘shrinking city’ solely based on population, as that description misses several confounding variables.  One is household size: it has been steadily decreasing over time (averaging 2.72 persons per hh in 1970, down to 2.16 in 2000), meaning fewer people occupy the same amount of space.  Furthermore, DC has indeed grown – it has more housing units than it did when its population peaked, and it has more jobs, too (and thus more office space).

So, no – the fact that DC’s population is lower today than in 1950 does not suggest the city has excess capacity.

A lot of other things are going well under current law, too. As Derek Thompson wrote in The Atlantic, Washington is the richest and best-educated metro area in America, leading the nation in economic confidence.

I don’t know that being rich proves success.  In fact, there’s plenty of evidence that areas like DC and SF are so rich because they are exclusive, and that high prices prevent the middle class from paying reasonable prices for housing.  Ryan Avent has written on this extensively. Simply put, more wealth is not the sign of a healthy economy.

Building height has little to do with affordability.  The argument that a limit on building height restricts housing supply and thus leads to higher prices is essentially the same argument made against Portland’s urban growth boundary. In both cases, it’s hogwash: if affordability were closely related to building height and density, New York City and San Francisco would be the two most affordable big cities in America.

This one is just absurd.  No one is proposing increasing building heights in DC just for the sake of going taller; the entire reason to change them would be to remove a constraint to growth.  The constraints to growth do indeed have costs.  Portland’s UGB is also a constraint.  Constraints do not need to be a negative if there are other means to allow growth; then they can shape that growth instead.  But to imply that elevation alone is the key to affordability is absurd. Asserting those who would change the height limit believe such absurdity is beyond reason.

In any event, denser doesn’t necessarily mean taller. These numbers may surprise you: Barcelona is denser than New York City, housing 41,000 people per square mile compared to New York’s 27,000. Barcelona’s beautiful and thriving, mid-rise central district L’Eixample is denser than Manhattan, at 92,000 people per square mile compared to Manhattan’s 71,000. It does not have buildings taller than Washington’s. In D.C., we could increase density substantially by incrementally converting many aging one- and two-story buildings in commercial and mixed-use districts to a still-human three to five stories.

The comparison of DC to Paris drives me nuts.  Paris is indeed dense, and mostly low-rise.  However, Paris has little of the small-scale rowhouse and single family homes that populate DC’s neighborhoods – if DC were Paris, those areas would be built out with 5-7 story apartments.

Yes, DC could likely increase density to Parisian levels and remain beneath the limit; but people seldom note what would be required to make that happen, what the trade-offs would be.  Would DC residents trade the complete redevelopment of its historic rowhouse neighborhoods for that to happen?  Benfield does not discuss the trade-offs.

One of Ryan Avent’s chief frustrations is a failure by height limit proponents to acknowledge the costs of the policy.  Ryan makes an estimate of those costs in his blog at The Economist:

Even simply taking the 22% figure, we’re left to conclude that the policy is extraordinarily costly. It represents a sigificant transfer of income from renters to homeowners. It represents a rise in the cost of business for all those operating in the area (which translates into more expensive government, as the impact of high housing costs on real wages forces the government to pay higher nominal salaries to attract qualified workers). And it captures the stultifying economic effect of crowding out in the Washington-area economy, as relatively location-sensitive activities (effectively, those not conducting business with the government) are driven out of the District into the suburbs or other metropolitan areas.

Regardless of what the actual cost is (and another Atlantic Cities piece quibbles with Ryan’s calculations), it is clear that the cost is substantial.  And, as the case of the Portland urban growth boundary mentioned above notes, there can be good reasons to have these constraining policies in place.  Avent continues:

There is a more practical case for limiting development, namely, that as Washington becomes more dense there will be negative spillovers accompanying the positive ones: more traffic, for instance, and more noise. Such costs aren’t negligible and often help explain NIMBY attitudes. Yet these shouldn’t dissuade Washington from making it easier to build. The net benefits of easier building should be large enough to help compensate losers and invest in projects to ameliorate negative effects.

Indeed, the discussion about DC’s height limit would be better off with a discussion of costs and trade-offs.  Likewise, an acknowledgement of  the fundamental truth about cities would help: the only constant is change.