Subtheme: Zoning and Housing Supply

One way to address the housing crisis from the supply side is to jumpstart housing production - i.e. to build more. The Affordable Homes Act notes that the state of MA needs to build at least 200,000 more housing units by 2030 to achieve a healthy vacancy rate and bring costs down. But to build more homes, more densely, we will need zoning reform or upzoning. Zoning is the set of municipal regulations that determines what kind of buildings can be built where. But years of exclusionary zoning practices have led to towns that favor large, costly, single-family residences which end up unaffordable for people with lower–and even moderate–incomes. To produce more housing, it will be necessary to reform zoning to allow for increased housing density, smaller homes, mixed-use zoning, and inclusionary zoning for the creation of affordable housing for low- to moderate-income people.

Years of exclusionary zoning practices have led to suburban towns that favor large, costly, single-family residences which end up unaffordable for people with lower–and even moderate–incomes. Students investigating this subtheme could look comparatively across Metro Boston towns and cities to see which ones have the most exclusionary zoning and who, demographically speaking, is affected. Student projects might also explore what could replace exclusionary, single-family zoning, such as “living little” and “living denser”. One area of exploration could be “Accessory Dwelling Units” a.k.a. “granny flats” which, following passage of the Affordable Homes Act, are now allowed across the state of MA.

Another potential direction is for students to demonstrate how restrictive current zoning practices are by depicting discrepancies between what is already built and what is allowed by zoning to be built. Looking comparatively across cities and towns in Boston, which cities have the most restrictive zoning? What percentage of existing properties couldn’t be built today? How can we make data-driven arguments to defeat some of the common pushbacks for zoning reform, like “we want to preserve the historical character of the neighborhood” or “housing for school age children will be a drain on town resources”?

Background Reading

  1. Houses are too expensive. Apartments are too small. Is this a fix? (Washington Post) – A data comic (!!) that explains exclusionary zoning in the US and outlines possible solutions.
  2. The illegal city of Somerville (City Observatory) – Discusses zoning in Somerville, including a laughable study by the city itself that showed that only 22 of the existing buildings would be permissible by today’s zoning laws. Students could undertake an analysis like this across several cities and towns in Metro Boston.
  3. Exclusionary by Design: An Investigation of Zoning’s Use as a Tool of Race, Class, and Family Exclusion in Boston’s Suburbs, 1920 to Today – A video as well as a report that goes through the history of exclusionary zoning practices in Boston.
  4. The Waning Influence Of Housing Production On Public School Enrollment– MAPC did this analysis to investigate the commonly held assumption that building housing for families with schoolage children will result in increased school enrollment (and therefore a drain on town resources). In both 2017 and 2024, they found no association between increased housing unit development and school enrollment.
  5. Minneapolis Land Use Reforms Offer a Blueprint for Housing Affordability – In 2023, Minneapolis did something pretty radical for US zoning: they eliminated exclusionary single family zoning and established that two-family and three-family buildings could be built on all residential lots in the city. This is a short report about preliminary outcomes from this and prior land use reforms.
  6. Living Little - A report about creative types of small housing that could be built in the MA suburbs to increase housing density with affordable units. This is a good introduction for anyone looking to work on Accesory Dwelling Units (ADUs).

Datasets for the Final Project

  1. Dataset of Metro Boston municipalities with single family zoning vs other housing zoning – The most restrictive form of zoning is single family zoning that doesn’t permit other forms of housing. Using this dataset you can compare which towns have the highest rates of this exclusionary zoning. Also included is demographic data about who lives in the single-family zoned areas vs who lives in the other housing zones.
  2. Metro Boston parcel data with zoning compliance flags – All Metro Boston properties with three columns added. Using these you will be able to see how m
    1. zoned_density – what unit density is allowed in this parcel?
    2. actual_density – what is the density (how many units) of what is built on this parcel?
    3. complies_with_zoning – does what is built on the parcel comply with the zoning?
  3. Metro Boston zoning compliance, aggregated to municipality – rates of zoning compliance/non-compliance by municipality, along with actual_density vs zoned_density statistics.
  4. Recent and under construction housing developments in Greater Boston - Data on new housing developments from MassBuilds. Can investigate where new housing is being built in relation to zoning and transportation. Can also analyze proportions of high density housing vs single family.
  5. Geographic data for making maps

Other Creative Data Ideas

  1. Real estate listings – E.g. Zillow, Redfin. Possibly a good source of photographic information about specific properties, including interior shots. Make sure you use these with credit to the source.
  1. Affordable Homes Act – See specifically the provision about Inclusionary Zoning by Simple Majority which help make upzoning easier as well as the Accessory Dwelling Units (ADUs) As-Of-Right which would allow anyone to build an in-law apartment or small residence on their existing property as a way to increase density. The bill: summary, proposed bill.
  2. The MBTA Communities Act. This legislation was enacted by the prior administration (Baker) and the state is now trying to implement it, but it is becoming controversial in some places. The basic idea is that towns served by the T or Commuter Rail have to upzone around the station service areas, an idea known as “transit-oriented development”.