Durham, Maine

Durham, Maine Accessory Dwelling Unit (ADU) Rules

City Acceptance Rating: 6/10
last updated: 2021

What You Need to Know:

Accessory apartments may be utilized for rental purposes as well as in-law accommodations subject to the following requirements:

  1. The dwelling must have only one main entrance and all other entrances must appear subordinate to the main entrance. An entrance leading to a foyer with entrances leading from the foyer to the two dwelling units is permitted. No open or enclosed outside stairways shall be permitted above the first story.

  2. The principal dwelling unit must have at least 1500 sq. ft. of floor area and the accessory apartment must not exceed 50% of the floor area of the principal dwelling unit. Floor area measurements must not include unfinished attic, basement or cellar spaces, nor public hallways or other common areas.

  3. Only one accessory apartment may be permitted per lot. It must be made part of the main residence, or located in a separate building whose primary function is not as a dwelling unit, such as a garage or barn.

  4. Accessory apartments may not be permitted for any nonconforming structure or use, where the nonconformity is due to the use of the premises, as opposed to nonconforming dimensional requirements

See full text here: Durham, Maine Performance Standards, Article 5, Page 19

Attached ADU, Convert Existing Space, Detached ADUChris LeeFriendliness Score 7/10, Durham, Maine, North of Portland