Zoning as we know it today originated in the 1920s. Even then its socio-economic impacts were controversial.
It was justified on the basis of a need to regulate “health and safety” but immediately (and still today) has been used to enforce rules that have nothing to do with that but a lot with making housing more expensive (such as quarter-acre minimum lot sizes and prohibiting any multi-family housing in an entire town).
During the 1950s through 1970s, the focus of concern was on the suburbs, because that’s where job growth was occurring. Now that prime land near jobs is increasingly within cities like Seattle, city zoning policy becomes critically important for access to economic opportunity.
It’s important to note that what makes zoning “exclusionary” isn’t its intent, but its effect. Using the law to make housing unnecessarily expensive stacks the deck against people with less rather than more money being able to live somewhere. There’s no way for “we don’t mean any harm” exemption for good intentions to mitigate its effects.
A majority of Seattle’s residential land is governed by Single Family 5000, Single Family 7200, and Single Family 9600 zoning. These zones make housing more expensive by ticking two definitional exclusionary zoning boxes:
One, they allow only single family detached homes. Size-wise, they basically allow a 30′ high residential structure covering up 35% of a lot. Non-exclusionary zoning would allow people to divide the same size of building into, for example, duplexes, triplexes, or stacked flats.
Two, they mandate large lot sizes. While at some point there is a health and safety lens on what constitutes a buildable lot, in many of Seattle’s older neighborhoods 3,000 SF lots are common. And they way lots are defined prohibits options for small homes to share land such as bungalow courts.
Here’s a walk through of articles from its too-long history in America:
Origins (1926). Section II of this article provides a history of how economically exclusionary zoning was originally rejected but subsequently allowed by courts.
Hope for Change (1971). During the 1960s the harmful effects of exclusionary zoning became so apparent there was hope it could be ended. Sadly this was not the case, although many tried.
Efforts to end it (2006). In the early 1970s the NAACP started one of the longest running court challenges focusing on the prohibition of multi-family hosing. Here’s a recap of what’s happened since.
Obama Administration (2013). The Obama administration made a stronger commitment to affirmatively housing than we’ve seen in the past, identifying exclusionary zoning as “a major barrier to unrestricted residential choice.”
Today (2014). As jobs have moved back into central cities in places like Seattle, exclusionary zoning in cities rather than suburbs has taken center stage: The New Exclusionary Zoning
Seattle today (2107). Here’s where Seattle stands today, according to city records: Percent of the city in single-family zoning (excluding parks and rights-of-way): 54%. Everything in light yellow, basically. How did we get here? Sightline has a detailed summary of Seattle’s 90 year history of expanding the footprint of exclusionary zoning.