NEW BEDFORD — Area homeowners could help to alleviate the city’s affordable housing crisis by slipping nearly invisible housing units into their neighborhoods.

Accessory dwelling units — ADUs for short — are small apartments built into single-family homes. They’re often called in-law apartments or guest suites, and they’re allowed under New Bedford’s zoning laws.

But the city has only permitted two of these units since 2007. A city spokesperson was unable to provide information on rejected or incomplete permit applications.

Advocates of ADUs say they could ease the housing crisis by squeezing a bit more density into already-developed neighborhoods. Unlike strategies that bulldoze existing properties to put up high-rise apartment buildings, ADUs can make room for more residents in basements, attics, and backyards — without changing the appearance or “character” of a neighborhood.


“To me, this is one of those policies that has tremendous upsides on so many levels with no real downsides,” said Amy Dain, a public policy researcher who has studied Massachusetts zoning laws around ADUs.

These units are generally more affordable because they’re small — in New Bedford, they have to be under 1,000 square feet. Building ADUs can also take some pressure off a hot rental market by increasing the housing supply.

New Bedford City Councilor Shane Burgo, who chairs the Affordable Housing and Homeless Affairs Committee, said ADUs wouldn’t solve the city’s housing shortage, but he thinks they could put a dent in it.

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“When it comes to the housing crisis, it’s one of those things where just building one type of housing is never going to be enough,” he said. “We need an all-tools-in-the-toolbox approach.”

AARP has endorsed ADUs because of the benefits they provide for seniors who want to age in place. Some move into the unit and rent out the main house for extra income, while others build the unit to house a caregiver. Or they might move into an ADU built on their children’s property to downsize and be close to help when they need it.

“Every elderly parent that ends up moving into their kid’s backyard is one less person in the condo market, or looking for a single-level home or something.” said Chris Lee, founder of Backyard ADUs, a New England construction company that specializes in ADUs. Most of the units he builds are for millennials and their aging parents consolidating households.

AARP has endorsed ADUs like this one in Florence because of the benefits they provide for seniors who want to age in place. Credit: Backyard ADUs

But the zoning code in New Bedford and the surrounding towns restricts where and how ADUs can be built. Some say those restrictions deter homeowners who otherwise would want to add a unit to their property.

In New Bedford, the unit has to be attached to the existing house — no backyard cottages allowed. That’s a problem, Lee said, because most people who are interested in building an ADU don’t want to live on top of it. Meanwhile, detached ADUs are allowed in Dartmouth, Fairhaven, and Acushnet.

New Bedford also bars homeowners from expanding the floor space of their home by more than 15% to accommodate an ADU.

Homeowners adding an ADU in New Bedford and Acushnet have to accommodate at least one extra off-street parking space. Dartmouth and Fairhaven require at least two. Burgo hopes the city can find ways to waive that requirement, especially in situations where seniors are downsizing into an ADU and don’t even drive anymore.

“We don’t want to have a parking issue where people aren’t able to find parking and it becomes too congested, so I can understand that being a concern,” he said. “But in some cases I feel like [the requirement] might be excessive.”

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The approval process can also stand in the way — New Bedford, Fairhaven, and Acushnet all require a special permit to build an ADU. That means homeowners have to present their proposal at a public meeting in front of a planning board and neighbors, who may or may not support them. And in New Bedford, homeowners have to renew the permit every two years. Burgo thinks that’s an “interesting barrier.”

Restrictions can discourage ADU production by reducing the number of homeowners who are eligible to build an apartment on their lot, said Dain, the policy researcher. The regulations tend to favor the affluent. Most of Dartmouth prohibits ADUs on lots smaller than 12,000 square feet. In Fairhaven, the lot has to be at least 22,500 square feet.

“To limit it, on lot size, is really, on average, limiting it for people who are working class and lower income,” she said. “It’s kind of saying, through law, ‘If you’re wealthy, you can have an ADU, and if you’re struggling, we don’t want you to rent out a property.’ It really has a class bias built into it.”

ADUs aren’t as rare in some of the towns around New Bedford. Dartmouth’s building commissioner estimated that his town has issued 12 to 15 ADU permits in the last year alone. Fairhaven officials said they also receive ADU permit applications, though it’s less than half-a -dozen every year. Acushnet’s building department initially offered to provide information on permits, but it did not respond to subsequent phone calls and voicemails.

Lot sizes may play a role. The median single-family lot in Dartmouth is nearly half-an-acre, but it’s less than a third of that size in New Bedford.

Another reason for the dearth of accessory units in New Bedford might be a lack of awareness. Public knowledge is one of the biggest barriers to producing these units in municipalities that allow them, Lee said.

“It’s not uncommon for a town to allow them in some form, and people just to not know about it,” he said. “As surprising as it may be, most people don’t read the zoning bylaw, so they just assume they can’t do it.”

Part of the state Legislature’s economic development bill would have limited the regulations municipalities can impose on ADUs, including special permits. But lawmakers failed to pass the bill before their session ended earlier this summer, so regulations are still up to city and town governments.

Burgo said he would be open to looking at ways to relax ADU restrictions in New Bedford at an upcoming meeting on zoning laws.

“Anything that we can do to chip away at the amount of units that we need here in the city is something that I’m willing to look at,” he said.

Dain said she understands homeowners’ anxiety about increased density and the potential for their property value to decrease when their neighborhood goes through change. But she says it’s counterproductive during today’s housing shortage. 

“You know, hell is other people” she said. “I think that heaven is other people, too.”

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