Legalizing Missing Middle Housing—Recommended Reforms for Massachusetts

Missing middle housing—a term referring to the building types between a single-family home and a mid-rise apartment building—is increasingly viewed by policymakers, housing advocates, architects, land use planners, and developers as one possible solution to the affordable housing crisis in Massachusetts and across the United States. This scale of housing is ideal for urban and suburban infill sites, fits a wide range of housing preferences, phases of life, and budgets, and is often built by developers invested in their local communities. However, missing middle housing is currently illegal to build in most of Massachusetts due to local zoning, even though new construction of middle housing was once commonplace. To restore the missing middle housing market in Massachusetts, the state should re-legalize small-scale multifamily housing by removing its effective statewide ban, along with a suite of other policy and regulatory proposals explored in this paper. Our six specific zoning and other regulatory recommendations include: re-legalizing missing middle housing types in all residential areas where only single-family homes are currently allowed; removing or decreasing residential parking minimums; reducing minimum lot sizes; increasing lot coverage and reducing setback restrictions; streamlining the development review process; and reforming building codes that limit missing middle housing.