Maine LD 2003 explained
Maine's LD 2003 (An Act To Implement the Recommendations of the Commission To Increase Housing Opportunities in Maine) was enacted in 2022, with towns required to comply in 2024, and is one of the most far-reaching pro-ADU laws in the Northeast. It preempts much of the town-level zoning that historically blocked ADU construction.
What the law actually requires
- Every Maine town must permit at least one ADU on a lot with a single-family, two-unit or three-unit home. Attached or detached.
- Towns cannot deny an ADU based on lot size alone. This is a major change - previously, minimum lot sizes effectively blocked ADUs on older, smaller parcels.
- Towns cannot deny an ADU based on on-site parking alone. Parking requirements are capped.
- Non-conforming lots still qualify if the ADU does not worsen existing setback violations.
- Short-term rental regulation remains under local control, so check your town's STR rules if Airbnb-style rental is the goal.
What towns can still regulate
- Height (typically capped at 25–30 ft)
- Total structure footprint and lot coverage
- Setbacks (LD 2003 does not override setback requirements)
- Shoreland zoning (still applies within 250 ft of water)
- Construction standards (building code compliance)
Common misconceptions
"My town already said no - does LD 2003 override that?" If your town said no prior to 2024, or on criteria now preempted such as lot size or parking, it is worth re-applying. Towns were not required to implement before January 1, 2024, or July 1, 2024 depending on how the ordinance is amended, and some are still catching up.
"Does this apply to my lot if it's in a subdivision with CC&Rs?" Private deed restrictions are not preempted by LD 2003. If your subdivision HOA prohibits ADUs via covenant, that remains enforceable.
What the permit package contains
Permits are pulled on every build, and ADU applications have gone through Sanford, Waterboro, Kennebunk, Wells and Limerick. The standard package is:
- Site plan showing setbacks and existing structures
- Elevation drawings
- Septic capacity calculation (if on private septic)
- DEP erosion control plan
- Town-specific application paperwork
Timing is the town's, not ours. Ask us what we saw most recently in yours.
Not sure what your town allows?
Book a free 15-minute land consult and we'll pull the town ordinance with you and confirm what's allowed on your specific lot.
The 2-minute calculator is on instant pricing. Published packages are on the ADU models.