Jamie Berry-Brennan was skeptical when his wife suggested they build an accessory dwelling unit for his parents on their Peaks Island property. 

But he also knew he wanted them closer.

His three young kids were growing up fast and rarely got to see their grandparents, who lived 100 miles away in Troy.

“It was just kind of sad. We wanted to try to figure out a way that they could see more of our family and we could see more of them,” he said. 

Finding a safe, comfortable and reasonably priced home on the island proved futile. Soon, an accessory dwelling unit started to look not just appealing, but like the only logical option.

Accessory dwelling units, or ADUs, are increasingly touted as a way to ease — if not solve — Maine’s stubborn housing crisis. Sometimes called in-law apartments or granny flats, these small homes, usually between 600 and 1,000 square feet, share a lot (and sometimes a wall) with an existing home.

Supporters say they’re ideal for people like the Berry-Brennans, who want to have aging parents nearby, or for adult children who may want to move home but can’t afford to buy in Maine’s competitive real estate market. They also work well as rentals for homeowners seeking supplemental income.

Lawmakers here have looked to western states like California where ADUs have become a mainstay of the housing market and seized on the idea of adopting them in Maine.

“People want options for their families,” said Maine House Speaker Ryan Fecteau, D-Biddeford, who championed the landmark 2022 housing law that set the stage. “(ADUs) are a great way to unlock housing for people who need it most.”

In an environment where large-scale projects are increasingly met with neighborhood resistance, ADUs are small and slot right in without drastically changing the character of a neighborhood.

Kristina Egan, executive director of the Greater Portland Council of Governments, a nonprofit group of municipalities working together on policies, including housing, called them one of the “least objectionable kinds of development.”

“We’re (still) going to need some large housing developments in order to reach our housing goals, but ADUs are a very gentle, incremental way of increasing the housing stock,” she said.

Until recently, the ability to build an ADU and what it might look like was dictated by zip code.

South Portland, for example, did not allow detached ADUs. Falmouth had an annual cap. Cape Elizabeth did not allow ADUs over 600 square feet. Wells banned them outright in some parts of town.

Now, these units are permitted on any single-family lot in Maine and legislators have been working feverishly to loosen statewide zoning and reduce any remaining barriers to their construction.

HOW DID WE GET HERE?

Maine’s recent land use reforms were borne out of necessity, said Matt Pouliot, an Augusta-based real estate agent and former state senator.

“It started with all of our constituents being like, ‘I can’t find a freaking place to live,'” he said.

The state underbuilt for decades, and real estate was already in high demand when the COVID-19 pandemic exacerbated pressure that had been mounting. Interest rates plummeted while demand spiked as people, suddenly with the ability to work remotely, fled crowded cities for Maine. The state’s already limited single-family inventory started shrinking rapidly as prices skyrocketed.

Families who may have ordinarily moved into a larger house or downsized, clutched tight to their über-low interest rates and stayed put, bringing the natural cyclical housing turnover to a halt.

“It was a moment in time in which it felt like everyone’s hair was on fire, but the fire had been burning for 20 years,” Pouliot said.

In 2021, the Legislature convened a statewide commission to study zoning and land use restrictions. Members, including legislators, affordable housing advocates, municipal representatives, planners, developers and other stakeholders, came up with nine recommendations, outlined in a 263-page report.

The recommendations effectively sought to “legalize housing,” said Pouliot, who was on the commission.

Many were rolled into LD 2003, a landmark bill passed in 2022 that opened up opportunities for denser development across the state by allowing accessory dwelling units on any property zoned for residential use, effectively eliminating single-family zoning.

Many towns bristled at being told what to do or how to grow. Some municipalities, like Portland, decided to go beyond what the law required and loosen zoning across the city, while others, like Cape Elizabeth, considered how to meet the requirements at just their most basic level.

But on both sides, municipal officials said they needed more time, and the July 2023 deadline was pushed back a year.

In the interim, a widely circulated 2023 state report found that Maine needed 84,000 new housing units by 2030 to meet the existing need and to accommodate expected population growth.

“I think the report was really important because it quantified how much we need and what the goal is,” said Egan, at GPCOG.

But more attention from legislators didn’t immediately lead to a rush of people clamoring to build an ADU.

“It was a step in the right direction, but even still, it’s not … opening up the floodgates on allowing people to use their land the way that they need to make it economically viable,” Pouliot said.

‘MORE HOUSING THAN WE HAD BEFORE’

Fecteau, the lead sponsor and champion of LD 2003, responded by introducing LD 1829.

Passed last year, it sought to make accessory dwelling units more prolific by allowing up to four units per lot in some areas and eliminating costly barriers like sprinkler requirements, owner occupancy mandates and changes to the state’s definition of “subdivision” to decrease planning board review. 

“It is a small contribution to the larger issue, but if a few people take advantage of it, that’s more housing than we had before,” Fecteau said.

The bill also introduced more controversial provisions like prohibiting minimum lot sizes greater than 5,000 square feet in parts of town connected to water and sewer, even if they’re outside of areas the town has designated for growth. It also bars limits on residential development in growth areas and allows for affordable housing projects to exceed certain height requirements, among other changes. 

Many pieces rankled communities, who argued that they trample on comprehensive plans while providing no additional funding for the infrastructure challenges that might follow.

But Fecteau argued that allowing more housing in areas already designated for residential use and where communities have made infrastructure investments is “just common sense.”

The bill was set to go into effect in July of this year for some towns and July 2027 for others. 

But legislators just pushed that off another year.

Rep. Amanda Collamore, R-Pittsfield, introduced a “fix it” bill this session to both correct some parts of the bill and also find a balance between local control and personal property rights.

The bill rolls back some of the gains made through LD 1829. For example, it increased the lot size minimums to 10,000 square feet and reinstated growth rate ordinances.

The bill, which passed this session, pushed implementation for all towns to July 1, 2027.

It remains to be seen whether the two most recent bills will have the desired impact.

And of course, neither is a panacea. Not all lots will be ideal for ADUs, even if zoning technically allows for them. The price, now comparable to what a standard single-family home cost before the pandemic, is prohibitive for many homeowners, especially those still working to pay off their primary home. And many simply have no interest in being landlords or sharing their space.

A TALE OF TWO COASTS

Accessory dwelling units are not unique to Maine. In California, these small houses represent an outsized share of the market, accounting for 21% of all homes permitted statewide in 2023, according to the California Department of Housing and Community Development.

The number of ADUs permitted there increased 20-fold between 2016 and 2023.

“It is a significant addition to their housing stock, and I think we will see something similar in Maine over time,” Fecteau said.

It’s hard to know how many ADUs have been built here since LD 2003 went into effect. Unlike California, there’s no statewide database and many of Maine’s smaller towns still keep paper records.

More data is expected soon, however, following legislation passed last year that requires municipalities with more than 4,000 residents to report a slew of housing data, including how many ADUs were permitted.

But even with that data in hand, without previous years to compare, it will still be several years before state officials can measure any concrete impact.

Egan, at GPCOG, thinks the number is likely pretty small. For now.

Preliminary data from GPCOG suggests an almost 30% increase in the number of detached ADUs built across the organization’s 29 member communities between 2024 and 2025.

Overall, the number increased from 136 to 176, but the percentage changes swung wildly from town to town. For example, Saco saw a 275% year-over-year increase, going from four to 15 permitted structures, while South Portland and Durham both saw a 67% decrease, dropping from nine to three and six to two ADUs, respectively.

At least 24 states have passed laws to encourage the use of accessory dwelling units, according to New York University’s Furman Center for Real Estate and Urban Policy.

California leads the pack, with 30 of 182 land-use reform bills focusing on ADUs. It’s followed by Oregon, with 12 of 56. Washington (seven of 43), Maine (six of 22), Rhode Island (six of 42), and Vermont (five of six).

‘SKEPTICAL’ TO ‘THANKFUL’

Berry-Brennan, on Peaks Island, hopes to see more families at least consider ADUs.

His parents, Bob Brennan and Barbara Adams, moved into a five-sided, roughly 950-square-foot home on the Berry-Brennans’ property in May 2024.

It wasn’t the easiest — or even the cheapest — process. Permitting took months and the land turned out to need extensive site work. All told, the ADU cost between $400,000 and $430,000, which they paid for with the proceeds from the sale of Brennan and Adams’ house in Troy.

But even with all that, he’d make the same decision again. In the almost two years since they moved, Berry-Brennan has seen more of his parents than his kids ever had.

He doesn’t see ADUs as a great money-maker, but for people searching for a unique solution to a family situation, he thinks it’s worth considering.

“I started out pretty skeptical, but after having gone through the process, I’m so thankful that we did it,” he said. “Having my parents around in their golden years, it’s been so nice, and something that we never would have been able to do if we hadn’t.”