Easthampton, MA

Easthampton, MA Accessory Dwelling Unit (ADU) Rules

City Acceptance Rating: 9/10 (10 is most accepting)

In 2021, Easthampton revised its zoning bylaw to allow homeowners to build accessory apartments in all zoning districts.

A building permit is required and a special permit in some instances (we can help with this).

ADUs are allowed on lots with Single-Family or Two-Family Homes.
The owner(s) of the detached single- or two-family dwelling must occupy one of the units as their primary residence at the time of occupancy. (No longer in compliance with the MA state ADU law)
A new detached ADU (and/or an attached unit consisting of new construction) must not exceed 900 square feet.
One new off-street parking space is required for the ADU. The new parking space materials must be consistent with the existing driveway.
- A waiver of this requirement may be granted for such reasons as, the resident has a disability or an occupant that does not own a vehicle.
If a new or expanded driveway is proposed within 10 feet of a side or rear lot line, a landscaped buffer of at least six feet—measured from the lot line—must be provided.
- Within this buffer zone, no parking, storage, or other use is permitted unless a written agreement is created and submitted to the building department between the applicant and neighbor.
No more than one ADU on a lot.
The principal dwelling and the ADU must remain in common or single ownership.

For tax purposes, a second dwelling unit may be considered a two-family dwelling for tax purposes.

Interior and Attached ADU Rules

An interior or attached ADU is required to be designed to maintain the appearance of a single- or two-family dwelling with a separate entrance.
The separate entrance must be either outside or through a shared entry with the primary dwelling.
All stairways to the ADU above the first floor must be within the building. If constructed outside the building, the stairs cannot face the street.
Maximum height, minimum setbacks, and maximum building coverage for a primary dwelling must be met.

Detached ADU Rules

An existing accessory structure can be converted to an ADU as long as no changes in footprint or height are made.
Maximum height, minimum setbacks, and maximum building coverage for a primary dwelling must be met.
A new detached ADU cannot be greater than 900 square feet.

See the full text here: Zoning Ordinance Section 8.5, Accessory Apartments, page 117