Several cities and towns in Maine have their own guidebooks describing local rules and regulations around ADUs. We’ve compiled them below for your convenience:
Biddeford
City ADU ordinance page outlining ADU allowances and standards.
📎 Biddeford ADU info: https://www.biddefordmaine.org/3127/Accessory-Dwelling-Units-ADUsbiddefordmaine.org
Cumberland
Local ADU regulations and rules (summarized by third-party ADU rule tracking).
📎 Cumberland ADU rules summary: https://backyardadus.com/adu-regulations-me/cumberland-me Backyard ADUs
Lewiston
Official municipal ADU info showing permitted ADU standards (size limits, owner occupancy rules, etc.).
📎 Lewiston ADU info: https://www.lewistonmaine.gov/1311/Accessory-Dwelling-Units lewistonmaine.gov
South Portland
📎 South Portland ADU Guidebook (PDF): https://www.southportland.gov/DocumentCenter/View/299/City-of-South-Portland-ADU-Guidebook-PDF South Portland
📎 South Portland ADU webpage with standards, permitting steps, and related links (including the guidebook and pre-application instructions): https://southportland.gov/206/Accessory-Dwelling-Units South Portland
Wells
ADU regulatory description indicating ADU permitting processes.
📎 Wells ADU rules summary: https://backyardadus.com/adu-regulations-me/wells-me Backyard ADUs
Yarmouth:
ADU regulatory description including ADU permitting processes: https://yarmouth.me.us/_T17_R88.php