Gov. Maura Healey wants to update the state building code by legalizing single-stair, mid-rise housing units to make it easier to construct more homes across Massachusetts, an effort that has raised safety concerns before.

Healey and housing advocates argue that the state’s current building code limits the feasibility of mid-rise housing developments because it typically requires two exit stairs for buildings above three stories or with long interior corridors.

An executive order the governor signed on Thursday, however, will create an advisory group tasked with studying whether single-stair construction in residential buildings above three stories would unlock housing development that the state sorely needs.

“We’re all about making it easier to build more housing across our state to drive down costs for everyone,” Healey said in a statement. “While the double stair requirement plays an important role in ensuring safety, it’s also holding us back from the type of housing construction we need to meet demand.”

The state Department of Fire Services declined to provide the Herald with a comment on Healey’s executive order on Thursday. Fire Marshal John Davine, in the past, though, has raised concerns about eliminating secondary egress requirements for buildings up to six stories.

Davine pushed back against single-stair residential buildings in a DFS newsletter in January 2025. The fire marshal pointed to how Plainville Fire Chief Robert Skinner attributed a secondary egress to saving about 20 people from injuries during an arson at an apartment building just months before.

Davine described the recommendation to move to single-stair construction as a “serious life safety hazard.”

“Modern homes and furnishings burn faster than ever before: removing yet another fundamental life safety requirement from the regulations intended to keep us safe,” he wrote, “would be a short-sighted and potentially deadly decision.”

Under Healey’s executive order, the advisory group will include fire service and building officials, national architectural experts, accessibility advocates and public safety professionals. Its work will include “comparing single-stair and multi-stair buildings, identifying necessary fire- and life-safety precautions, and recommending targeted updates to the State Building Code.”

The governor’s office is touting Harvard’s Joint Center for Housing Studies for identifying 4,955 “underutilized parcels” across Greater Boston, ranging from parking lots to vacant, single-story retail buildings located within three-quarters of a mile from rapid transit.

JCHS has estimated that the sites could “produce up to 130,000 new housing units through urban infill alone if single stair is allowed up to six stories and 24 units.”

“Every safe, evidence-based strategy to build more homes is needed to meet the housing demands we’re facing, and single-stair multifamily residential buildings could offer us a new way to increase our housing supply,” Housing and Livable Communities Secretary Ed Augustus said in a statement.

“This executive order will bring together the right people … who will help us explore the possibilities and find the best path forward,” he added.

Healey’s administration says it will be following the lead of New York City and Seattle, cities it says have permitted single-stair buildings up to six stories for decades. Tennessee, Montana and Connecticut have also enacted similar legislation under specified safety conditions.

The International Association of Fire Fighters has spearheaded a “coordinated effort” to block single-stair residential buildings “before they become the new normal.”

“We all want to see more affordable housing built, but not at the expense of people’s lives,” General President Edward Kelly has said in the past. “One stairwell means one way in and one way out. When firefighters are going up, and families are trying to get down, that’s a recipe for disaster.”