Greater Boston Considers Relaxing ADU Rules as Housing Shortage Deepens

Cities in the region want to increase flexibility for homeowners who want to build 'granny flats' on their property.

2 minute read

July 27, 2021, 8:00 AM PDT

By Diana Ionescu @aworkoffiction


1719 house in Salem, Massachusetts

AlexiusHoratius / House in Salem, Massachusetts

Accessory dwelling units, granny flats, in-law units—whatever you call them, the concept of building additional housing units on single-family lots has taken off across the country. Now cities in the Boston area, which have long restricted ADU construction, are "mulling so-called accessory dwelling units as one way to add housing without drastically altering the feel of neighborhoods," reports Andy Rosen. "A 2018 study by the free-market Pioneer Institute found that only 37 of 100 municipalities surrounding Boston allowed ADUs for rental to anyone other than a homeowner’s family or caregiver. And in many of those cities and towns, the rules were so strict that few people were building them."

"This spring, both Arlington and Salem passed measures to allow such units. Framingham and Barnstable, among others, are considering doing so, as well. Boston is expanding a similar 2019 program, and some candidates in the city’s mayor’s race are calling for even more permissive rules to encourage them." As Rosen writes, "[s]upporters say they are good tools to help older people and those on fixed incomes stay in their homes by converting unused space into income-producing property, while providing relatively low-cost rental stock."

The Boston program also aims to "bring unpermitted units into compliance and to ensure they meet safety standards." While "ADUs won’t come close to solving the region’s housing crunch on their own," more permissive zoning and "a thoughtful approach could house thousands of people across the region."

Sunday, July 11, 2021 in Boston Globe

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