Maine Forces Cities to Allow at Least 2 ADUs on Residential Lots

A new state law bars local jurisdictions from restricting ADUs in residential areas.

1 minute read

November 2, 2025, 7:00 AM PST

By Diana Ionescu @aworkoffiction


Aerial view of Brunswick, Maine with colorful sunset clouds.

Paul VanDerWerf from Brunswick, Maine, USA, CC BY 2.0, via Wikimedia Commons / Wikimedia Commons

A new state law in Maine will streamline regulations for accessory dwelling units and bar municipalities from restricting them in residential areas, reports Chris Costa for News Center Maine.

According to Costa, “LD 1829 encourages new construction of accessory dwelling units, known as ‘ADUs,’ by pulling back zoning restrictions that differ widely from town to town and setting new statewide standards, including allowing three dwelling units on every lot.”

The law required cities to allow at least four units per lot in “designated growth areas” and reduces minimum lot sizes for ADUs. It also prohibits cities from imposing stricter height limits, setbacks, and other dimensional standards for ADUs than for single-family homes and does not require owners to occupy one of the units. 

ADU builders say the standardized rules help reduce the cost of construction, allowing them to plan for similar designs and regulations across the state.

Thursday, October 30, 2025 in News Center Maine

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