How Massachusetts Zoning Reform Impacts ADU Laws

Cities and towns have until February to adjust their zoning codes to reflect more permissive rules for accessory dwelling units.

1 minute read

September 5, 2024, 5:00 AM PDT

By Diana Ionescu @aworkoffiction


Two colorful Victorian houses in Conway, Massachusetts.

Homes in Conway, Massachusetts. | Hans Hansen / Adobe Stock

A new Massachusetts state law will require cities and towns to revise their zoning laws when it comes to accessory dwelling units (ADUs), reports Scott Merzbach in the Amherst Bulletin.

The state law, the Affordable Homes Act, preempts some local requirements, such as Amherst’s owner-occupancy requirement and prohibitions on free-standing units. However, towns “may add designs and standards, architectural character and other criteria, within reason,” according to Amherst Senior Planner Nate Malloy. In Northampton, “second units of any size are already allowed in Northampton’s residential districts, so long as they meet minimum design criteria, setbacks, open space, heights and other dimensional criteria.” 

Some small and rural communities with septic systems will likely see slower change, as a state law limits the number of bedrooms by lot size. According to William Dwyer, a Planning Board Clerk in the small town of Hadley, “revisions to zoning rules in Hadley will likely set reasonable limits, such as maintaining rear and side setback requirements, the need for the dwelling to be on a foundation and for water and septic or sewer connections to the main home.”

Tuesday, September 3, 2024 in Amherst Bulletin

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