Lincoln, MA

Lincoln, MA Accessory Dwelling Unit (ADU) Rules

City Acceptance Rating: 10/10

Last updated: 6.21.2024

What You Need To Know

In Lincoln, ADUs are allowed both within a single family home as well as in a detached structure.  Additionally, through the Affordable Accessory Apartment Program in Lincoln, ADUs are allowed under other guidelines, detailed below, with the intention of creating affordable housing to families and individuals whose income is between 60%-80% area median income.  They emphasize a desire to serve populations such as families, single parents, veterans, seniors, town employees, and employees of small local businesses.

Type of ADU Permit Required

ADUs within an existing dwelling require a building permit whereas an ADU in an accessory structure, outside the main structure, or through the Affordable Accessory Apartment Program require a special permit.

ADU Rules

For ADUs not part of the Affordable Accessory Apartment Program:

  • ADUs (not part of the Affordable Accessory Apartment Program) are limited to 5% of the residential units in Lincoln.  

  • The ADU is limited to 1,200 square feet

    • An ADU within a single family home cannot be greater than 35% of the floor area of the single family home and the ADU combined.

      • EX. 2,500 square foot single family home +1,200 square foot ADU = 3,700 square feet total x .35 = 1,295 square feet. 

      • In this example, the ADU would have to be smaller.

  • An ADU is only permitted on lots that contain at least 40,000 square feet.

  • The owner of the property must own both the ADU and the single family home and live in either the ADU or the single family home.

  • For both building and special permits, dimensional floor plans and a site plan must be submitted showing the following:

    • Location, setbacks, height, and location of a parking space for the ADU

    • ADUs must meet setback and height requirements laid out in the zoning bylaw for primary structures or accessory structures depending on the location.  

    • Provision for sewage must be made per the requirements of the Board of Health.

    • Proper ingress and egress as well as one parking space must be provided.

    • The primary residence must retain the appearance of a single family home.

    • If the ADU is rented, it must be rented for a minimum of seven days

ADUs through Lincoln’s Affordable Accessory Apartment Program are intended to:

  • Provide families and individuals whose income is between 60%-80% area median income (AMI) housing

  • Provide young families, single parents, veterans, seniors, town employees, and employees of small local businesses housing

  • Allow residents of Lincoln with modest income to get income that will allow them to stay in their homes

  • Add units to the Subsidized Housing Inventory at little cost to Lincoln

  • Spread affordable housing throughout Lincoln

  • Contribute to efficient use of land and structures in Lincoln

  • Add units without changing the footprint of the existing structure

Requirements

  • Special permit through the Zoning Board of Appeals

  • A deed restriction

    • This is a 15 year deed restriction recorded at the South Middlesex Registry of Deeds

    • The deed restriction ends if the property is sold

    • The deed restriction can be voluntarily terminated with 60 days notice at the end of a tenant’s lease

  • An affirmative fair marketing plan

    • This refers to the process of selecting tenants in a way that advances fair housing and equity.  

    • Homeowners are required to select tenants from a waiting list generated by the Affordable Accessory Apartment Program

    • Family members or employees of the homeowner may not be a tenant through the Affordable Accessory Apartment Program

  • The home must retain the appearance of a single family home

  • The ADU will have a separate entrance

  • Off-street parking is available

  • The changes that are made must not be a detriment to the neighborhood

  • The ADU may not exceed 1,200 square feet or more than 35% of the home’s square footage

  • The septic system is adequate

  • The plans provided are certified by an architect

Homeowner Benefits

  • Homeowners qualify for a real estate tax exemption on the portion of property dedicated to an Affordable Accessory Apartment.  Essentially, homeowners are not charged for the portion of property used for affordable housing purposes. 

  • Zero interest loans totalling $25,000 over a ten year period will be granted to homeowners.  

    • After ten years the loan is forgiven

Resources:

https://www.lincolntown.org/DocumentCenter/View/27060/Affordable-Accessory-Apartment-Program

Attached ADU, Convert Existing SpaceGuest UserGreater Boston, Friendliness score 10/10, Lincoln, Massachusetts