Accessory Dwelling Units | Broken Zoning, Unaffordable Homes: What Can Be Done?

What’s the Problem?

Massachusetts is in the midst of a housing crisis that threatens our communities, our economic success, and our quality of life. For years now, advocates have been calling for an update to the Commonwealth’s outdated zoning and housing rules. Businesses are debating whether to locate in Massachusetts because the high cost of housing makes it difficult to attract and retain employees. And communities across the Commonwealth are struggling to create vibrant, walkable places where people want to live and work.There are several bills pending before the Massachusetts state legislature that would update our outdated zoning laws and help the Commonwealth build the housing it needs. These bills include the Governor’s Housing Choice bill and the Great Neighborhoods bill, which, taken together, will offer meaningful reform and help us meet today’s needs and tomorrow’s demand.

But time’s running out for both pieces of legislation – the Massachusetts Legislature needs to pass the bills by the end of the legislative session on Tuesday, July 31. As part of an ongoing series, we’re highlighting some of MAPC’s priorities that we hope will be included in the legislation that makes it to the Governor’s desk.

One Solution: Accessory Dwelling Units

An accessory dwelling unit above a garage. Photo by radworld, Creative Commons.

Accessory dwelling units (ADUs) are apartments located inside a single-family home or in a detached structure, such as a garage or carriage house. Sometimes known as granny flats, in-law apartments, or secondary dwelling units, they include a kitchen, bath, and usually at least one bedroom.

ADUs are a low-impact way to diversify housing options, provide more affordable homes for young families or older adults, and help the homeowner with additional income through rent. Accessory apartments are so unobtrusive that they usually can’t be seen from the street. But about a third of communities in the MAPC region don’t allow them and another third place complicated restrictions on how they can be used.

The Great Neighborhoods bill would make it much easier to build an accessory dwelling unit by giving property owners across the state the right to build ADUs inside single-family homes on lots of at least 5,000 square feet.

Under the legislation, an ADU must have a separate entrance and cannot be sold separately from the main house. The legislation includes several elements to ensure accessory apartments will be successfully integrated in a community. For example, a home on a septic system would have to comply with Title 5 wastewater regulations. Municipalities would have the power to limit ADUs to five percent of total units or to require that either the primary home or accessory unit be owner-occupied. If cities and towns want to be more flexible, they can do so – but these basic guidelines would set the standard for ADUs throughout the Commonwealth, allowing for more small housing units in a non-obtrusive way that’s free for the government and generates income for homeowners.

Accessory apartments are one market-based solution to providing more homes and a greater diversity of types of homes. This will be increasingly important as our population continues grow older over the coming decades.

Take action!

Making it easier to build Accessory Dwelling Units is just one idea that’s currently part of the pending Housing and Zoning bills. With just a few weeks left in the legislative session, it’s important that the legislature take up these bills and pass meaningful reform. There are common sense measures we can and should make this year to encourage more homes to be built and provide needed zoning tools to our municipalities.

Your legislator needs to know that these solutions have constituent support! Please take the time – now – to reach out to them and tell them that you want these important bills to move forward this session.

Click here to find out who your legislators are and then call or email them to make your voice heard! Click on the names of your state senator and state representative at the bottom of the page to find their phone number, email, and mailing address.

You can use this message for your call or email:

[Ask to speak with a staff member in the Senator or Representative’s office]

“Hello, my name is [NAME] from [CITY, TOWN, or NEIGHBORHOOD] in the [Senator/Representative]’s district.

I support legislation updating our outdated zoning and housing rules, including the Governor’s Housing Choice bill and the Great Neighborhoods bill. We’re in the middle of a housing crisis and we need to do something this session to address it. Please weigh in with the [Speaker/Senate President] and ask them to move these important bills and encourage reform.

Thank you for your time!

Learn More

Read the other blogs in MAPC’s series “Broken Zoning, Unaffordable Homes: What Can Be Done?”

  • Housing Choice Plus – MAPC is advocating for what we call “Housing Choice Plus” and asking that the Legislature add some important reforms from the Great Neighborhoods bill to the Housing Choice Bill. Learn more about what that means!
  • Multi-Family Housing – Metropolitan Boston needs to build an average 16,000 new homes a year to meet demand. But between 2010 and 2017, we averaged just over 10,000 units per year. One of the most important things that lawmakers can do to address the housing crisis is to set a standard for multi-family housing, which is defined as having three or more housing units in a building.