Harvard Says Loosening This Mass. Building Code Could Spur Over 100,000 New Housing Units

As Massachusetts leaders keep searching for solutions to the housing crunch, a top academic institution is pointing to the role the state’s building codes play in restricting multifamily development.

For years, any buildings of more than three stories or 12 units in the state have been required to have at least two staircases. But a new report from Harvard University’s Joint Center for Housing Studies says that changing code to allow larger buildings with a single staircase could help bring on more housing in land-constrained cities like Boston and Cambridge.

The proposed change would raise the maximum height for single-staircase buildings to six stories, a change it estimates could yield as many as 130,000 new housing units on ready-to-develop parcels across the state. Several experts who spoke about the proposal on an Oct. 10 webinar said it could unlock new development opportunities the Boston area hasn't seen in decades.  

"If nearly a fraction of those were approved, it would have an impact on our housing goals and the vibrancy of our cities," Utile Associate Sam Naylor, whose design firm partnered on the report, said on the webinar.

Naylor said legalizing mid-rise, single-stair housing would help developers build on the smaller plots of land that are widespread around Boston and Cambridge. These parcels are usually underutilized because they are too small for the type of density that developers are looking to add to offset their costs.

Many developers combine parcels into bigger sites to make these projects work, or the parcels lay underdeveloped. Naylor said that with the proposed building code change, there would be approximately 5,000 parcels — properties minutes from transit stops and that are vacant or have low-rise retail use — that could be developed now.

The first Massachusetts building codes were adopted in 1630, the oldest in the U.S, but the first official statewide code wasn’t created until 1974, according to the Harvard report.

With that statewide code, Massachusetts implemented new requirements for buildings of more than two stories to have at least two forms of egress. In 2017, the code was amended to raise the limit to three stories.

A large portion of multifamily development seen in Boston and Cambridge in recent decades has been podium style building, also known as a five-over-one, consisting of five stories over a podium of concrete or steel. This style became popularized because it maximized the number of units created while staying below the threshold of a high-rise building — a classification that comes with more fees.

"The development community is effectively de facto forced to use the double-loaded corridor, podium building to deliver net new unit housing in a lot of contexts," Fulcrum Land & Infrastructure partner Ian Hatch said on the webinar.

Across the globe, single-stair developments, also known as point access blocks, have been the dominant form of multifamily housing except in the United States, according to the Harvard report. Many countries have developments ranging from five to eight stories using single-stair access. A handful of states and provinces in North America have begun to adopt single-stair building codes, most recently British Columbia, followed by Seattle, New York City and Honolulu.

Hatch said it isn't easy to make these PAB developments pencil when a developer is only able to deliver 12 units. He said land values are too high, bidding is too competitive and there are other zoning restrictions placed on top that make it difficult for smaller projects.

"What you have is a situation where, no matter what the zoning says, a large swath of the communities that we love really can't generate net new housing units at scale," Hatch said. "These are the very transit-rich, walkable, bikeable places that we must have most of our new housing production.

But there are safety concerns associated with loosening the building code.

The restrictions placed on PABs were used as a fire safety precaution to help residents evacuate from properties. In recent years, fire codes have changed and fire equipment and mitigation practices have modernized.

"We have many more active and passive fire protection measures that are rare abroad and help make our buildings just as safe,” Naylor said.

Eduardo Mendoza, policy director of Los Angeles' Livable Communities Initiative, said there is typically common ground between building code officials and fire engineers about the design of the building and its technical components. But there are other groups that don't want to loosen codes in fear that there could be major repercussions.

Mendoza became a major proponent of reforming building codes in California, particularly near Los Angeles, where he has made headway in upping the height maximum for these types of developments.

"There are other groups that see this as an existential threat to their institution," Mendoza said. "From my experience, I'm seeing a bit of a lag from the building code world that has not yet adopted or come to terms with this massive national housing crisis that we are all experiencing.”

The Harvard report’s proposed changes to the building code would also allow for better unit diversity in developments, including more flexibility with family-sized units. Merge Architects founder Elizabeth Whittaker said that not everyone wants to live in a single-family home, and building more housing that is welcoming and efficient is crucial for families that want to stay in Boston.

"The single-stair will unlock preconceptions about real estate in the city and families that can actually stay with dignity and joy," Whittaker said.