Height limit questions, answers, and more questions
The question over whether or not to raise DC's height limit has come up periodically for several years, but gained new traction earlier this month when some members of Congress asked for a study about modifying the height limit legislation. With the possibility of actual change looming, more and more people are weighing in.
Most height limit opponents have so far based their position on the argument that taller buildings downtown would be more economically efficient, and that allowing some offices to be located outside downtown is costing DC a lot of money.
The latest to do so is David Schleicher at The Atlantic Cities, who opposes the height limit and poses a series of questions to supporters.
Having long advocated for raising the limit strategically, both downtown and in surrounding areas, I cannot be characterized as a height limit supporter. But I also think that the economic arguments put forth by the loudest height limit opponents, including Schleicher, are too narrow and miss important considerations.
That in mind, Schleicher's questions are worth discussing.
Supply and demand
Schleicher argues that DC's height limit is restricting the supply of available buildings, which is making it impossible to meet the demand for office space in the city. He says,
But if Height Act proponents think limits on supply do not increase prices, why not? Is it some distinction between housing and offices and other markets? If so, what is your model of how office and housing markets work?Obviously there is a connection between supply and demand. But is the height limit really limiting DC's supply?
There is currently around 100 million square feet of office space in downtown DC, which makes it the 3rd largest downtown in America after New York and Chicago. Despite no skyscrapers, downtown DC currently has a greater supply of office space than downtown San Francisco, Boston, Philadelphia, or Los Angeles.
More importantly, DC's supply of potential building space is not anywhere close to being maxed out under current regulations. The height limit is not currently restricting supply in the vast majority of DC. It is only restricting supply within the area roughly bounded by Massachusetts Avenue and the National Mall.
It's true that DC's historic rowhouse neighborhoods are largely off-limits to significant densification, but large sections of central DC are nonetheless available. Even with the height limit, there is room for at least double downtown's current square footage in underbuilt areas of NoMa, Southwest, and along the Anacostia and Potomac waterfronts. Without touching DC's height limit or its historic rowhouse neighborhoods, there is room for decades of additional growth within a radius of 2 miles of the Capitol.
There would be even more room available for infill if the decision were ever made to redevelop Roosevelt Island, Bolling Air Force Base, or National Airport. Doing so would surely be controversial, but should at least be discussed in an honest assessment of options.
So it is simply not true that the height limit is restricting building supply in DC overall.
It is, however, true that the supply of buildable space is being limited in that geographically small downtown area. This brings up Schleicher's next questions.
Where and how to grow
Schleicher asks a few questions:
Why do you think development should be spread out? What effect do you think limiting heights has on agglomeration, including the depth of local markets and information spillovers? Do you believe in a single optimal city form? And why do you think DC captures it? Or are height limitations somehow a particularly good fit for a national capital?Opponents of the height limit like to ask why DC's existing limit is so special. If the height limit happened to be 20 stories instead of what it is, would supporters still claim it's the perfect regulation?
Opponents need to answer the opposite question.
"Downtown DC" used to only mean a few blocks near Pennsylvania Avenue. Now it means a larger area, spanning from New Hampshire Avenue on the west to Union Station on the east. Since downtown is the only area being functionally limited by the height act, what about the current extents of downtown DC make it the perfect geography?
Downtown grew from that area around Pennsylvania Avenue to its current extents because of the height limit. Since that growth happened, buildings at 19th and Eye Streets are not generally considered to be much more poorly located than buildings at 12th and G. In the future, if the height limit is kept, downtown will again grow to encompass NoMa, Southwest, and the waterfronts, and they will not be considered any more out of the way than the West End is considered today.
If it was OK for downtown to expand to include the West End, why isn't further expansion OK too? What's so magical about today's definition of downtown, which is different from the definition a few decades ago and will surely be different again in the future?
Theoretically it would be possible to cluster all the office space in downtown DC in no more than a dozen super-tall skyscrapers covering only a couple of blocks. And some day in the future we might even be able to fit all of it in one single thousand-story building, covering only a single square block. Would that be ideal?
If maximum agglomeration were desirable, it follows that we'd want a much smaller downtown than we have today.
Granted, that thousand-story example is reductio ad absurdum, but the point is simply that there's nothing magical about the current definition of downtown DC, so any argument that's based on solving the problem of restricted supply within that current definition is necessarily flawed.
So the question is not "how can we fit more office space in the area currently defined as downtown?" Rather, it's "where do we want future office space?"
If we want to have more space specifically at, say, Farragut Square, then we can raise the height limit around Farragut Square without eliminating it completely for all of downtown. I'm OK with that.
But we also have to recognize that there are many benefits to spreading development around a little bit. We don't want sprawl, of course, but the region is better off for having vital mixed-use neighborhood uptowns like Bethesda and Clarendon spread near the core.
If all the office space is clustered in a small office ghetto downtown, that deprives the surrounding neighborhoods of key mixed use elements. Not only daytime office workers, but also office-reliant retail and support services that are necessary for any successful mixed-use district.
The desirability of mixed use neighborhoods is one of the most basic premises of contemporary urbanism, and it's why many people who care about good cities want to spread some office space around outside of downtown districts. Unless we're prepared to force everyone to live within walking distance of downtown, we need healthy neighborhood uptowns that are mixed-use.
Economists seem to have a difficult time grasping this point. It's probably true that it's economically more efficient to cluster offices more than we're currently doing (though surely not to that single thousand-story building extent). But the economic models being employed so far in this debate don't take into account livability or good urbanism. The benefits of spreading some office development to uptown districts aren't captured if all you're thinking about is property values at 12th and G.
And it's not just the uptowns that reap the livability benefits of the height limit. Downtown DC does too.
With the exception of New York, no large city in the US has fewer surface parking lots in its downtown than Washington.
Surface parking (red), above-ground garages (yellow) and park space (green) in 4 US cities in 2011. Left to right, top to bottom: Houston, Milwaukee, Little Rock, Washington. Images from Old Urbanist.
Because of the height limit, it is less economical here to let properties lay fallow than in any of our peer cities. This means there are no gaps in the urban fabric, which improves downtown's walkability.
But again, the near-certain likelihood that gaps in the urban fabric would develop without a height limit is not something that's captured in the economic models.
Questions for opponents
Schleicher's questions deserved discussion, but height limit opponents need to answer some questions themselves. The economists who seem to be largely driving the movement to repeal have so far focused on a narrow set of arguments, and ignored or attempted to marginalize any broader issues. That's not a recipe that will result in buy-in from anybody who doesn't already agree.
Some questions that height limit opponents more fervent than myself need to answer:
- What about the current extents of downtown DC make you think it is the perfect geography in which to cluster office development?
- Do you accept that there are reasons some people like the height limit which cannot be captured in traditional cost-benefit models?
- Instead of repealing the height limit, would you accept modifying it to permit taller buildings only at specific and limited locations? If so, how might you go about determining those locations?
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