Another column from Paul Krugman today on the ways that US-style zoning laws are detrimental to economic opportunity is a pleasant reminder that the role of building regulations in broader questions of inequality is no longer such a fringe issue. Particularly in places with the greatest “shortage of cities”—where the gap between available housing and the demand for it is greatest, and prices are, as a result, most out of whack—the basic idea that zoning is one of the main drivers of that shortage is increasingly well understood, even if not everyone agrees with it.

But while these regressive, environmentally and socially unsustainable regulations often get reduced to “zoning,” there’s a lot more going on in American cities than that. Take, for example, Houston, which is famous (in its way) for being the only major US city without comprehensive zoning. It’s a frequent comeback for those who claim that zoning and regulation is behind American urban sprawl: If that’s so, then how do you explain Houston, which combines a lack of zoning with picture-perfect urban sprawl?

Houston City Hall, where they don't write zoning codes. Credit: Wikimedia Commons
Houston City Hall, where they don’t write zoning codes. Credit: Wikimedia Commons


The answer is illuminating in two directions. First, Houston is a case study in how non-zoning regulations can produce sprawl. But it also shows how Houston’s lack of traditional zoning really does open up some windows that don’t exist in other places—and what the consequences are in practice. This post will focus on the first direction; we’ll dive into the second in a later post.

You might divide Houston’s non-zoning regulations into two buckets. The first are regulations that essentially reproduce zoning without the name. These have been covered well by a number of people, including Michael Lewyn in 2005, Chris Berry in 2001, and more recently, Zillow’s Sklyar Olsen. (There’s also a good amount of discussion in William Fischel’s Zoning Rules!) A big one is that neighborhoods can establish private covenants that regulate building density, form, and use—and the city of Houston will sue to enforce them, rather than requiring private individuals who are party to the covenant to sue. Essentially, Houston enforces private zoning codes with public money and resources.

Houston also directly regulates the built environment in ways that most cities do within a zoning code. Up until 1998, the city mandated that homes be built on lots no smaller than 5,000 square feet—well over the minimums that predominate in older, denser cities. (Since then, the city has relaxed the minimum lot area requirements in some places, with consequences that are worth exploring in another post.) Similarly, minimum parking regulations are a staple of American zoning; Houston’s are no different even if they appear outside a comprehensive zoning code. One-bedroom apartments must have 1.33 parking spaces available; single family homes must have two. In a special case of backwardness, bars must have ten parking spaces for every thousand square feet of floor area. As elsewhere, the result of all of this is to a) create a built environment in which surface parking lots are common, pushing buildings farther apart and making walking both more burdensome and less pleasant; and b) force tenants and customers to effectively pre-pay for the major costs of car use, making the price difference between driving and not much smaller, and inducing more people to drive.

More interesting for our purposes here, however, are regulations beyond the scope of normal “zoning”—that is, the use and form of buildings. These regulations aren’t necessarily unusual, but they go beyond the question of directly regulating buildings, to regulating the spaces in between. For example, street widths: Houston’s planning department suggests that major arterials ought to be at least 100 feet wide, a size that makes crossing anywhere but at a signalized intersection virtually impossible, and generally precludes a pedestrian-oriented street that is safe and pleasant to walk along. On these streets, intersections are also supposed to be no less than 600 feet apart, roughly twice the length recommended for a high-quality pedestrian environment—and especially harmful when it’s dangerous to cross the street without a traffic light.

Especially when combined with parking requirements, the effect of these non-zoning regulations is to create streets that look like this:


For reasons of both comfort and practicality, this is not a street that very many people will choose to interact with outside of a car. The sidewalks are wedged between fast-moving cars and parking lots; to get to any of the businesses that line the street, a pedestrian will have to navigate spaces designed for cars, which is unpleasant, time-consuming, and dangerous. Because the city code requires plentiful off-street parking, because the street width has been optimized for car travel, and because private covenants generally enforce the separation of commercial and residential areas, the distance between these shops and most people’s homes is likely to be too far to walk anyway. And because transit use generally involves some walking from a stop to your final destination, it will be greatly discouraged as well.

Given a transportation environment that has discouraged all non-car modes, developers will end up building housing far from jobs and amenities, assuming that their buyers will drive. In this way, auto-oriented arterials function in a similar way to highways: they reduce the costs (financial, time, and otherwise) of driving, increase the costs of other modes, and encourage sprawl.

That creates both environmental and social unsustainability, pushing people to rely on emissions-heavy, and personally expensive, transportation. As work from the Center for Neighborhood Technology has shown, people who live in more car-dependent neighborhoods can pay significantly more for transportation, often to the point that it crowds out other necessities. Even where housing is affordable, then, the total location costs of that housing, including transportation, might not be. And people who cannot drive at all—either because they cannot afford to own a car, or because they are not physically able—are left to rely on public transit that is almost necessarily impractical, because of the physical layout of streets.

While zoning is the most common land use tool, and while it is fairly characterized as being a big contributor to sprawling development patterns throughout the country, it’s only one example of the kind of regulation that leads to sprawl. Houston’s combination of parking requirements, prescribed street widths, and the public enforcement of private covenants accomplishes the same sprawling results. So while these sorts of street regulations don’t directly enforce the kind of low-density housing that we criticize zoning for, they do strongly encourage it. They deserve a place in our conversations about housing accessibility, and access to opportunity, in Houston and beyond.