Building Missing Middle Housing: Six Actions Massachusetts Can Take Beyond Policy Reform

Missing middle housing such as duplexes, triplexes, and small multifamily buildings once formed the backbone of many Massachusetts communities. Today, this scale of housing—viewed as one solution to the current housing crisis—is effectively absent from the new construction market. As Part 1 of my paper series “Unlocking the Missing Middle” explored, this is largely due to local zoning’s power to limit medium-density housing—and along with it, economies of scale ranging from construction efficiencies to financing products. Part 2 of the series showed how zoning and regulations such as parking requirements, minimum lot sizes, and building codes severely restrict the feasibility of middle-scale homes. Even if Massachusetts were to remove these barriers through land-use reform, the state will still face a disconnect between policy change and production. In the third and final paper in the series, I propose six actions legislators, developers, entrepreneurs, funders, planners, and advocates can work toward to ensure that new rules translate into new middle housing units.

Key Questions and Recommended Actions

These actions are designed to address key questions facing missing middle adoption and the entrenched barriers to building these homes efficiently, economically, and at scale. 

1. What will new missing middle homes look like?

Recommendation: Create a statewide missing middle design guide and locally implemented pre-approved plan set for Massachusetts.

Even where zoning allows middle-scale housing, communities and builders often struggle to visualize what these new homes will look like. A statewide design guide, paired with locally calibrated, pre-approved construction plans, could reduce architecture costs, help communities understand how new housing fits their unique context, and accelerate permitting.

Resources from design guides to plan sets in Vermont, Chattanooga, and South Bend show how clear visuals and feasibility-tested plans can demystify density and support faster approvals. A Massachusetts pre-approved plan set could offer clarity, predictability, and cost savings, especially to small-scale developers.

Figure 1: The Vermont Homes for All Toolkit Features Five Missing Middle Home Types

Age-in-Place, Narrow Lot, Village, and Side-by-Side are predevelopment-ready missing middle building designs based on local vernacular architectural precedents, each with several customization options.

Source: Vermont Department of Housing and Community Development

2. Who will build new missing middle homes?

Recommendation: Stand up a missing middle builder training cohort and construction trades pipeline.

Decades without new middle-scale building have left Massachusetts with a shallow bench of small developers who specialize in medium-density infill housing, yet the demand for smaller, more diverse home types is rising.

Cities like Austin have created developer training cohorts that help new builders learn pro formas, construction strategies, local codes, and financing structures. These programs also broaden participation, attracting women, BIPOC developers, and community-rooted builders who have historically been excluded from development. A Massachusetts cohort could pair technical training with hands-on project coaching, helping cultivate the next generation of small-scale developers equipped to deliver middle housing types.

3. Where will these new homes be built?

Recommendation: Work with development-ready communities and community groups to pilot statewide missing middle initiatives—and build new homes.

Some communities are better positioned than others to implement missing middle reforms quickly. Municipalities with updated zoning, political support, and clear development processes could serve as early pilot sites for plan-set adoption, modular projects, or streamlined permitting.

International examples, such as Canada-based mddl’s Municipal Fast-Track program, show how pairing standardized designs with efficient approvals can cut permitting timelines to as little as 10 days. In Massachusetts, MBTA Communities Act municipalities or Housing Choice Designation communities might serve as first adopters—demonstrating middle housing feasibility and building public support for middle-scale infill.

4. How will middle housing be delivered efficiently and at scale?

Recommendation: Advocate for and implement construction innovation to accelerate timelines and decrease cost in middle housing delivery.

Because middle-scale homes aren’t being built at volume, they lack the economies of scale enjoyed by single-family production homebuilders or large multifamily developers. Off-site construction, including modular and panelized building systems, can help close this cost gap.

Massachusetts is already exploring this potential: the Metropolitan Area Planning Council is developing a regional off-site construction strategy and exploring opportunities for a new modular manufacturing facility. Andover-based Reframe Systems, with its proprietary combination of micro-factories and robotics-enabled assembly, is showing how modular can reduce construction costs by 35 percent and make scattered-site infill viable. Updating zoning, building codes, and approval processes to fully enable modular construction could help Massachusetts accelerate housing production.

5. How will new middle housing be funded?

Recommendation: Create or convene novel funding sources.

Financing missing middle housing presents a bottleneck. Traditional lenders view these projects as too small, too risky, or too unconventional. To fill this void, innovative models like Colorado’s Middle-Income Housing Tax Credit, impact investors such as Arctaris, and Oregon’s Missing Middle Housing Fund are pioneering new capital stacks for middle-income, middle-scale homes.

Massachusetts could follow suit by creating a middle housing tax credit, expanding its Workforce Housing Initiative eligibility to include middle-scale typologies, and supporting predevelopment loan funds designed for small infill developers.

6. Who will coordinate statewide missing middle activity?

Recommendation: Establish a statewide missing middle office or dedicated position to lead cross-sector efforts and ensure their viability.

Finally, coordinating all these efforts, including design, permitting, training, public education, and funding, requires dedicated state capacity. States such as Oregon have created offices focused on helping cities implement statewide missing middle land-use reforms. A Massachusetts Missing Middle Division within the Executive Office of Housing and Livable Communities could:

• Guide municipalities in adopting statewide reforms,
• Coordinate plan sets and modular initiatives,
• Run training cohorts,
• Provide technical assistance to small-scale developers, and
• Lead public education efforts to build community support.

A centralized home for missing middle implementation would ensure that policy changes translate into production on the ground.

By adopting these six recommended actions, Massachusetts can begin to rebuild a long-dormant segment of its housing market. Missing middle housing once shaped the character of New England neighborhoods; bringing it back is a key step in easing the state’s housing shortage.