HOVERING BY THE FAIRY TALE playground, by the pumpkin carriage and turreted castles, behind the swings, was a wall of murky glass, an abandoned factory. There were no other factories around my childhood park in Newtonville, just a pleasing selection of unique houses, arranged along sidewalks that led to a village center with a candy shop and train stop.

Back then, my favorite stories involved pumpkin carriages. Now I am more focused on stories about zoning policy, so I started wondering about that spooky factory by the swings.

Zoning came to fame in 1926 when the Supreme Court ruled that the Village of Euclid, Ohio, could use zoning to prohibit heavy industry from locating by homes. Keeping noxious factories out of neighborhoods is a straightforward and admirable goal for zoning policy.

Zoning’s whole story, however, is more nuanced and less admirable. Zoning stabilizes the built environment of neighborhoods, and stability generally bolsters human flourishing. It is easy to understand why people would want to protect their beloved neighborhoods from change, and from dragons. But sometimes the outcomes of zoning policies are sub-optimal, which I will discuss here. And sometimes the story takes a sinister turn.

Zoning has reinforced social segregation. Zoning often works to shut the disenfranchised out from enjoying public goods shared by the privileged.

The abandoned factory of my childhood memories was not like nineteenth century riverfront factories, brick splendor punctuated by regular windows. It was also no concrete box of the modern era. It was all murky glass, pre-modern, ghostly. I recall no signs on the building, no indication of what was fabricated within. It was so out of place that I questioned if I had made it up. Google proved useless to answer.

I turned to my parents’ photo albums. There I found black-and-white 1977 proof of its existence: My big brother on a swing, the backdrop a glass mosaic in shades of grey, attractive, and creepy. I asked my Facebook friends: What was made in the factory?

For old factories in Greater Boston, guess textiles, shoes, candy, or bonnets. Newtonville’s Security Mills factory produced wool textiles.

I Googled again, now with a name. The National Park Service has a PDF of a typewriter-typed history of Newton’s architecture: “Justification of the need for a zoning ordinance and the fact that not everyone had such a high-minded approach to development could be shown by the development of the Security Mills in Newtonville.”

In 1921, the Newtonville Improvement Society tried to prevent the construction of the manufacturing complex by the park in a residential neighborhood. The city held several special hearings, but chose not to take the property by eminent domain. There was no zoning to stop it. The factory was built only months before the passage of Newton’s original zoning ordinance.

It was a classic zoning narrative – factory versus neighbors, like in Euclid — playing out by my childhood playground, where my kids now play, with no cool decrepit factory in sight. In the 1990s, the long vacant property finally got redeveloped.

Newton needed to decide what could replace the factory, on the park, next to an excellent elementary school, and a short walk to CVS and the commuter rail. One suggestion was townhouses. From a regional perspective, this is the perfect location for multifamily housing.

From a local perspective, though, the housing would bring new kids to the school system, perhaps more than the system was ready to accommodate. And while some new residents would likely commute by train, others would drive, potentially to exacerbate rush hour headaches. So, the city permitted an assisted living facility — no kids and barely any traffic generation in rush hour. There was a need for assisted living; the facility is well-used.

Yet, decisions like this, repeated in location after location, limit housing options for people not seeking senior-oriented or single family housing.

In my study of zoning in 100 municipalities of Greater Boston, I found that 55 municipalities have adopted zoning for age-restricted multifamily housing (for occupants who are 55+). From 2015–2017, a quarter of the municipalities permitted age-restricted projects.

A quarter of the zoning codes also include provisions that limit or prohibit three-bedroom dwellings in multifamily buildings. Widespread restrictions favoring certain types of housing hold the market back from meeting our population’s diverse needs.

Sometimes exclusion is an unintended side effect of well-meaning decisions; sometimes it is the intention of policymakers.

In the 1960s and ’70s, in the era of white-flight from the city, our suburbs systematically down-zoned — increasing minimum lot sizes and eliminating much of the zoning for garden apartments.

Wayland explained its strategy to exclude apartments in its 1962 master plan. “As population pressure has heightened, the Planning Board and the Town Meeting have reappraised Wayland’s position within the western section of the metropolitan area and have increased the lot area and frontage requirements for residential districts and maintained the single family residence requirement. These policies are primarily responsible for the growth of Wayland in a manner that has encouraged investment in homes and gives evidence of creating a most satisfactory environment for family living,” the plan reads.

In 1969, Massachusetts adopted Chapter 40B, the so-called anti-snob zoning act, to authorize certain types of dense development and affordable housing that municipalities were not allowing, and to encourage local zoning reform. Still, decades later, Greater Boston does not have the zoning in place to meet the population’s diverse needs for housing.

As Newton’s 2007 comprehensive plan illustrates, the politics of reform are tricky. “Those living in predominantly single-family areas generally wish them to stay that way,” the plan reads. “They wish those areas neither to be marginally blurred into resembling the mixed single and two family areas nor to be compromised by large-scale multifamily developments being plopped into their midst. Those living in mixed single and two-family areas similarly value the diversity such areas afford, and wish not to see them blurred into a monoculture of look-alike development. Those living in large-scale multifamily areas chose that context and similarly value it and seek to protect it from excessive extension or change.”

Wayland’s 2016 housing plan echoes the same sentiment: “Within existing residential neighborhoods, new multi-family housing is generally not recommended because of concerns that it would alter the single-family character of most of Wayland’s neighborhoods.”

People are still concerned, as they were in Newtonville in 1921, that “not everyone has such a high-minded approach to development.” But also, not everyone takes a high-minded approach to zoning.

Zoning has been used to separate noxious factories from homes, to protect the look and function of beloved neighborhoods, and to keep certain people from crossing the town gates. We need to zone for all types of housing. We need to plan for diverse communities with diverse needs. There are ways to protect what we love about Greater Boston while building more housing.

Amy Dain is a public policy researcher and consultant who recently wrote the report, “The State of Zoning for Multi-family Housing in Greater Boston.”