The Somerville City Council recently signaled support for Gov. Healey’s executive order that favors single-stair residential construction.

By Harry Kane

City Councilors offered their support for Governor Maura Healey’s Executive Order No. 651, which aims to facilitate safe and affordable single-stair multifamily residential buildings in the Commonwealth.

While fire professionals raised safety concerns, housing advocates strongly support single-stair, mid-rise buildings as a reform to ease housing shortages. A technical advisory group was established to examine data and provide recommendations.

“This is a resolution about single-stair buildings, which sounds like an incredibly boring topic, but is actually incredibly exciting,” said Ward 3 City Councilor Ben Ewen-Campen during the May 14 City Council meeting.

Updating the building codes to allow single-stair multifamily residential buildings may “enable efficient use of land and support feasible mid-rise residential development,” according to the executive order.

The Commonwealth plans on adding over 220,000 new homes statewide within the next 10 years, and some 140-180,000 of those new homes would be in the Greater Boston area.

Currently, the building code in Massachusetts requires two exit staircases for all buildings above three stories, restricting “missing middle” apartment buildings on smaller lots, according to the executive order.

If policymakers can reform the building code, mid-rise residential buildings (up to 4-6 stories) would contain only one central staircase. Developers could then be capable of creating more compact buildings on smaller urban lots with reduced construction costs.

An October 2024 study from the Boston Indicators group – Legalizing Mid-Rise Single-Stair Housing in Massachusetts – concluded single-stair construction could unlock 130,000 new units in Greater Boston.

The study refers to the status quo double-loaded podium buildings as “antiquated” and points to single-stair residential buildings that are also referred to as Point Access Blocks (PABs), as a collection of building types that don’t require dimly lit interior hallways and can create “more livable” units with direct sunlight and cross ventilation.

PABs “are well suited to small and medium scale parcels, and with one less stair, and way less hallway, can achieve much higher floor plan efficiencies than their double-loaded counterparts,” according to the study.

The extra staircase adds $200,00 — $500,000 in construction costs, the study says, and can account for 10 percent of the total floor area in typical six-story complexes on 3,000 – $5,000-square-foot parcels.

Advocates of single-stair buildings are growing in number, pointing to sustainable housing models that maximize space and reduce construction costs to address housing shortages. But firefighters have deep concerns, citing compromised evacuation rescue operations due to a loss of the critical life safety feature.

Ewen-Campen acknowledged concerns about fire safety during his briefing. “I know that many firefighters, including here in Somerville, are really concerned about the idea of single-stair buildings,” he said. “I very much respect that.”

On May 8, Somerville Firefighters Local 76 wrote on Facebook that they “stand against legislation that would allow new construction in Massachusetts to be built with only one means of egress.”

Ewen-Campen provided a response to concerns, saying, “There is also a lot of evidence that this code was written before the invention of a lot of modern fire suppression technology that has made single-stair, some argue, just as safe.”

Governor Healey’s executive order, signed on February 12, includes the formation of a technical advisory group to conduct an analysis, recommend updates to the Massachusetts Building Code (780 CMR), and mitigate health or safety impacts.

The final report will reflect the recommendations of the technical advisory group within 12 months of the executive order.

“I’m really looking forward to seeing whether this is something that can get traction in Massachusetts,” said Ewen-Campen. “I think it could make a real difference.”

City Councilor-at-Large Ben Wheeler expressed confidence in the technical advisory group’s expertise, but added, “I want to recognize that some firefighter groups, including Somerville firefighters Local 76, oppose single-stair design.”

A letter of support from local architect Sean Selby was submitted along with the resolution. Selby says single-stair buildings would be safe and would bring smaller, local developers into the community on sites that would otherwise sit dormant.