An Act to Update the Laws Regarding Housing Developments and
Maine Legislature, Session 132, LD 2173
Committee: Housing and Economic Development
Sponsors: COLLAMORE, CURRY, FECTEAU
Amends: 25 MRSA §2463-B, 30-A MRSA §4360, 30-A MRSA §4364, 30-A MRSA §4364-A, 30-A MRSA §4364-B, 30-A MRSA §4364-D, 30-A MRSA §4364-E, 30-A MRSA §4401, 30-A MRSA §4402

Legislative Document
No. 2173
H.P. 1461
House of Representatives, January 27, 2026
An Act to Update the Laws Regarding Housing Developments and 
Accessory Dwelling Units
(EMERGENCY)
Approved for introduction by a majority of the Legislative Council pursuant to Joint Rule 
203.
Reference to the Committee on Housing and Economic Development suggested and 
ordered printed.
ROBERT B. HUNT
Clerk
Presented by Representative COLLAMORE of Pittsfield.
Cosponsored by Senator CURRY of Waldo and
Representatives: Speaker FECTEAU of Biddeford, ROBERTS of South Berwick.
Emergency preamble.  Whereas, acts and resolves of the Legislature do not 
become effective until 90 days after adjournment unless enacted as emergencies; and
Whereas, the majority of the changes made by this legislation will become applicable 
to certain municipalities on July 1, 2026; and 
Whereas, this legislation modifies recently enacted provisions of law that will 
become applicable to many municipalities without the modifications made by this 
legislation on July 1, 2026; and
Whereas, this legislation creates a grace period for certain municipalities to delay 
compliance with a recently enacted provision of law if the municipality makes a filing with 
the municipality's county register of deeds prior to July 1, 2026; and 
Whereas, this legislation contains other critical changes that must go into effect as 
soon as possible to allow municipalities to implement the Legislature's intent and remain 
in compliance with the law; and
Whereas, this legislation will not go into effect prior to July 1, 2026 unless enacted 
as an emergency; and
Whereas, in the judgment of the Legislature, these facts create an emergency within 
the meaning of the Constitution of Maine and require the following legislation as 
immediately necessary for the preservation of the public peace, health and safety; now, 
therefore,
Be it enacted by the People of the State of Maine as follows:
Sec. 1.  25 MRSA §2463-B, as enacted by PL 2025, c. 385, §1, is amended to read:
§2463-B.  Fire protection in accessory dwelling units
Fire suppression sprinklers are not required for an accessory dwelling unit unless the 
accessory dwelling unit is within or attached to a structure of that contains, or will contain 
upon completion of construction, more than 2 dwelling units, including accessory dwelling 
units.  As used in this section, "accessory dwelling unit" has the same meaning as in Title 
30‑A, section 4301, subsection 1‑C.
Sec. 2.  30-A MRSA §4360, as amended by PL 2025, c. 385, §3 and affected by 
§23, is further amended to read:
§4360.  Rate of growth ordinances
1.  Ordinance review and update.  A municipality that enacts a rate of growth 
ordinance shall review and update the ordinance at least every 3 years to determine whether 
the rate of growth ordinance is still necessary and how the rate of growth ordinance may 
be adjusted to meet current conditions.
1-A.  Definition; common scheme of development.  For the purposes of this section, 
"common scheme of development" means a plan or process of development that:
A.  Takes place on contiguous parcels or lots in the same immediate vicinity; and
B.  Exhibits characteristics of a unified approach, method or effect, such as:
(1)  Unified ownership, management or supervision;
(2)  Sharing common equipment or labor; or
(3)  Common financing.
2.  Differential ordinances.  A municipality may enact rate of growth ordinances that 
set different limits on the number of building or development permits that are permitted in 
designated rural areas.  A municipality may not enact or enforce rate of growth ordinances 
that limit residential development in designated growth areas, as defined in section 4301, 
subsection 6‑C, except as authorized by this chapter subsection 3.
3.  Ordinance requirements.  A municipality may adopt a rate of growth ordinance 
only if:
A.  The ordinance is consistent with section 4314, subsection 3;
B.  The ordinance sets the number of building or development permits for new 
residential dwellings, not including permits for affordable housing, at 105% 130% or 
more of the mean number of total permits issued for new residential dwellings within 
the municipality during the 10 5 years immediately prior to the year in which the 
number is calculated.  The mean is determined by adding together the total number of 
permits issued, excluding permits issued for affordable housing, for new residential 
dwellings for each year in the prior 10 5 years and then dividing by 10 5;
C.  In addition to the permits established pursuant to paragraph B, the ordinance sets 
the number of building or development permits for affordable housing at no less than 
10% of the number of permits set in the ordinance pursuant to paragraph B; and
C-1.  The ordinance does not require a development permit for affordable housing as 
defined in section 5246, subsection 1; 
D.  The number of building or development permits for new residential dwellings 
allowed under the ordinance is recalculated every 3 years.; and
E.  Within a designated growth area, the ordinance does not limit the development 
permits allowed per project or per common scheme of development to a number that 
is less than 35% of the allocated permits for that area.
Sec. 3.  30-A MRSA §4364, first ¶, as amended by PL 2023, c. 192, §1, is further 
amended to read:
For an affordable housing development approved on or after the implementation date 
defined in subsection 1-A, a municipality with density requirements shall apply density 
requirements in accordance with this section, and, for an affordable housing development 
approved on or after the implementation date defined in subsection 1-B, a municipality 
with height restriction requirements shall apply additional height allowance requirements 
in accordance with this section.
Sec. 4.  30-A MRSA §4364, sub-§1-A, as enacted by PL 2023, c. 192, §3, is 
amended to read:
1-A.  Implementation date; density requirements.  For purposes of this section, with 
respect to applying density requirements under this section, "implementation date" means:
A.  January 1, 2024 for municipalities for which ordinances may be enacted by the 
municipal officers without further action or approval by the voters of the municipality; 
and
B.  July 1, 2024 for all other municipalities.
Sec. 5.  30-A MRSA §4364, sub-§1-B is enacted to read:
1-B.  Implementation date; height allowances.  For purposes of this section, with 
respect to applying additional height allowances under this section, "implementation date" 
means: 
A.  July 1, 2026 for municipalities for which ordinances may be enacted by the 
municipal officers without further action or approval by the voters of the municipality; 
and
B.  July 1, 2027 for all other municipalities. 
Sec. 6.  30-A MRSA §4364, sub-§2-A, as enacted by PL 2025, c. 385, §5 and 
affected by §23, is amended to read:
2-A.  Additional height allowance.  Except as otherwise prohibited under Title 38, 
chapter 3 and municipal shoreland zoning ordinances, a municipality shall allow, subject 
to review by a municipal fire official or designee, an affordable housing development to 
exceed any municipal height restriction by no less than one story or 14 feet but only up to 
a total building height of 55 feet.  To be eligible for an additional height allowance pursuant 
to this subsection, an affordable housing development must be reviewed by a fire official 
or designee during the development approval process; must comply with minimum lot size 
requirements in accordance with Title 12, chapter 423-A, as applicable; and must: 
A.  Be in a designated growth area of a municipality as identified in a comprehensive 
plan adopted pursuant to subchapter 2; or
B.  Be served by a public, special district or other centrally managed water system and 
a public, special district or other comparable sewer system.
This subsection may not be construed to provide additional authority to a fire official or 
designee or to establish new standards for the review of an affordable housing development 
by a fire official or designee other than the requirements established in the Maine Uniform 
Building and Energy Code, adopted pursuant to Title 10, chapter 1103.
Sec. 7.  30-A MRSA §4364, sub-§5, as amended by PL 2025, c. 385, §6 and 
affected by §23, is further amended by repealing the first blocked paragraph and enacting 
the following in its place:
A municipal ordinance may not require minimum standards for subsurface wastewater 
disposal systems other than what is required pursuant to rules adopted by the Department 
of Health and Human Services governing subsurface wastewater disposal pursuant to Title 
22, section 42. 
Sec. 8.  30-A MRSA §4364-A, as amended by PL 2025, c. 385, §§7 to 12 and 
affected by §23 and amended by c. 388, Pt. D, §37, is further amended by amending the 
section headnote to read:
§4364-A.  Residential areas,; generally; up to 4 dwelling units allowed
Sec. 9.  30-A MRSA §4364-A, sub-§1, as repealed and replaced by PL 2025, c. 
385, §7 and affected by §23 and amended by c. 388, Pt. D, §37, is repealed and the 
following enacted in its place:
1.  Use allowed.  Notwithstanding any provision of law to the contrary, except Title 
12, chapter 423-A, for any area in which residential uses are allowed, including as a 
conditional use, the following are permitted uses:
A.  At least 3 dwelling units, attached or detached, inclusive of accessory dwelling 
units, per lot; and
B.  At least 4 dwelling units, attached or detached, inclusive of accessory dwelling 
units, per lot if the lot is located in a designated growth area, as identified in a 
comprehensive plan adopted pursuant to subchapter 2, or the lot is served by a public 
water system and a public sewer system.
A municipality may allow more units than the minimum number required by this 
subsection.
Sec. 10.  30-A MRSA §4364-A, sub-§1-A, as enacted by PL 2023, c. 192, §7, is 
amended to read:
1-A.  Implementation date.  For purposes of this section, "implementation date" has 
the same meaning as in section 4364, subsection 1‑A. means:
A.  January 1, 2024 for municipalities for which ordinances may be enacted by the 
municipal officers without further action or approval by the voters of the municipality; 
and
B.  July 1, 2024 for all other municipalities.
Sec. 11.  30-A MRSA §4364-A, sub-§2-A, as enacted by PL 2025, c. 385, §9 and 
affected by §23, is amended to read:
2-A.  Lot Limitations on municipal ordinances related to lot size and density 
allowance for private property requirements.  Notwithstanding any provision of law to 
the contrary, except Title 12, chapter 423‑A, this subsection applies to any area in which 
residential uses are allowed, including as a conditional use.
A.  If a lot is located in a designated growth area and is served by a public, special 
district or other centrally managed water system and a public, special district or other 
comparable sewer system, a municipal ordinance may not require a minimum lot size 
requirement may not exceed that exceeds 5,000 square feet and a density requirement 
may not exceed 1,250 square feet of lot area per dwelling unit for the first 4 dwelling 
units and 5,000 additional square feet of lot area per dwelling unit for subsequent units 
may not require more than 1,250 square feet of lot area per dwelling unit for the first 4 
dwelling units.
B.  If a lot is located outside a designated growth area and in an area served by a public, 
special district or other centrally managed water system as defined in Title 22, section 
2601, subsection 8 and a public, special district or other comparable sewer system, a 
municipal ordinance may not require a minimum lot size requirement may not exceed 
that exceeds 5,000 square feet and a density requirement may not exceed 5,000 square 
feet of lot area for the first 2 dwelling units contained within a single structure, not 
including accessory dwelling units may not require more than 5,000 square feet of lot 
area per dwelling unit for one dwelling unit or 10,000 square feet of lot area for 2 
dwelling units within a single structure.
C.  If a lot is located in a designated growth area without a public, special district or 
other comparable sewer system, a municipal ordinance may not establish minimum lot 
size requirement may not exceed the minimum lot size required by Title 12, chapter 
423‑A and the density requirement or calculation may not be more restrictive than 
required by Title 12, chapter 423‑A requirements, density requirements or 
requirements for other calculations related to dwelling units per lot area other than what 
is required pursuant to rules adopted by the Department of Health and Human Services 
governing subsurface wastewater disposal pursuant to Title 22, section 42.
If 4 or fewer dwelling units have been constructed on a lot as a result of the allowances 
under this section or section 4364‑B, the lot is not eligible for any additional increases in 
density, including under section 4364, unless more units are allowed by the municipality.
Sec. 12.  30-A MRSA §4364-A, sub-§4, as amended by PL 2025, c. 385, §11 and 
affected by §23, is further amended by repealing the first blocked paragraph and enacting 
the following in its place:
A municipal ordinance may not require minimum standards for subsurface wastewater 
disposal systems other than what is required pursuant to rules adopted by the Department 
of Health and Human Services governing subsurface wastewater disposal pursuant to Title 
22, section 42.
Sec. 13.  30-A MRSA §4364-A, sub-§5-A, as enacted by PL 2025, c. 385, §12 and 
affected by §23, is amended to read:
5-A.  Planning board approval not required.  A For any area in which residential 
uses are allowed, including as a conditional use, a municipality may not require planning 
board approval for to establish 4 or fewer dwelling units within a single structure on a lot 
or for accessory dwelling units.
Sec. 14.  30-A MRSA §4364-B, sub-§1, as amended by PL 2025, c. 385, §13 and 
affected by §23, is further amended to read:
1.  Use permitted.  Except as provided in Title 12, chapter 423‑A, a municipality shall 
allow an accessory dwelling unit to be located on the same lot as a single-family dwelling 
unit or multi-unit 2-unit or 3-unit residential structure in any area in which residential uses 
are permitted, including as a conditional use, in accordance with this section.
Sec. 15.  30-A MRSA §4364-B, sub-§1-A, as enacted by PL 2023, c. 192, §13, is 
amended to read:
1-A.  Implementation date.  For purposes of this section, "implementation date" has 
the same meaning as in section 4364, subsection 1‑A. means:
A.  January 1, 2024 for municipalities for which ordinances may be enacted by the 
municipal officers without further action or approval by the voters of the municipality; 
and
B.  July 1, 2024 for all other municipalities.
Sec. 16.  30-A MRSA §4364-B, sub-§2, ¶B, as amended by PL 2025, c. 385, §14 
and affected by §23, is further amended to read:
B.  Attached to or sharing a wall with a single-family dwelling unit or multi-unit 
residential structure; or
Sec. 17.  30-A MRSA §4364-B, sub-§3, ¶A, as amended by PL 2025, c. 385, §15 
and affected by §23, is further amended to read:
A.  At least one accessory dwelling unit must be allowed on any lot where a single-
family dwelling unit is the principal structure is a single-family dwelling unit or 2-unit 
or 3-unit residential structure; and
Sec. 18.  30-A MRSA §4364-B, sub-§7, as amended by PL 2025, c. 385, §18 and 
affected by §23, is further amended by repealing the first blocked paragraph and enacting 
the following in its place:
A municipal ordinance may not require minimum standards for subsurface wastewater 
disposal systems other than what is required pursuant to rules adopted by the Department 
of Health and Human Services governing subsurface wastewater disposal pursuant to Title 
22, section 42.
Sec. 19.  30-A MRSA §4364-B, sub-§8, ¶A, as amended by PL 2023, c. 192, §19, 
is repealed.
Sec. 20.  30-A MRSA §4364-D, sub-§1, ¶C is enacted to read:
C.  "Small child care facility" has the same meaning as in Title 22, section 8301-A, 
subsection 1-A, paragraph E.
Sec. 21.  30-A MRSA §4364-D, sub-§2, as enacted by PL 2025, c. 288, §2, is 
amended to read:
2.  Location of child care.  A child care facility or a family child care provider is must 
be a permitted use in a municipal area that is zoned for residential purposes,.  A family 
child care provider or small child care facility located in an area zoned for residential 
purposes must be subject to the same zoning requirements for other residential property as 
a single-family dwelling unit.
Sec. 22.  30-A MRSA §4364-E, as enacted by PL 2025, c. 364, §2 and reallocated 
by RR 2025, c. 1, Pt. A, §42, is amended by enacting after the first paragraph a new 
paragraph to read:
This section does not apply to areas allowing industrial uses.
Sec. 23.  30-A MRSA §4401, sub-§4, ¶H-2, as amended by PL 2025, c. 385, §20 
and affected by §23, is further amended to read:
H-2.  This subchapter may not be construed to prevent a municipality from enacting an 
ordinance under its home rule authority that otherwise regulates land use activities.
A municipality may not enact an ordinance that expands the definition of "subdivision" 
except as provided in this subchapter.  A municipality that has a definition of 
"subdivision" that conflicts with the requirements of this subsection at the time this 
paragraph takes effect on September 24, 2025 shall comply with this subsection no 
later than July 1, 2027, except that if a municipality that has a conflicting definition 
files its conflicting definition in the county registry of deeds applicable to that 
municipality by July 1, 2026, that definition remains valid until January 1, 2028.  A 
filing made pursuant to this paragraph must be collected and indexed in a separate book 
in the registry of deeds for the county in which the municipality is located.
Sec. 24.  30-A MRSA §4402, sub-§6, as amended by PL 2025, c. 385, §21 and 
affected by §23, is further amended to read:
6.  Division of new or existing structures.  Beginning January 1, 2026, a A division 
of a new or existing structure into 3 5 or more dwelling units whether the division is 
accomplished by sale, lease, development or otherwise in a municipality where the project 
is subject to municipal site plan review.
A.  For the purposes of this subsection, "municipal site plan review" means review 
under a municipal ordinance that sets forth a process for determining whether a 
development meets certain specified criteria, which must include criteria regarding 
stormwater management, sewage disposal, water supply and vehicular access and 
which may include criteria regarding other environmental effects, layout, scale, 
appearance and safety.
B.  The municipal reviewing authority in each municipality shall determine whether a 
municipal site plan review ordinance adopted by the municipality meets the 
requirements of paragraph A.
Sec. 25.  Application.  Notwithstanding any provision of law to the contrary, those 
sections of this Act that amend the Maine Revised Statutes, Title 30-A, sections 4364, 
4364-A, 4364-B and 4364-E apply to municipalities for which ordinances may be enacted 
by the municipal officers without further action or approval by the voters of the 
municipality beginning July 1, 2026 and apply to all other municipalities beginning July 1, 
2027.
Sec. 26.  Effective date; growth ordinances.  That section of this Act that amends 
the Maine Revised Statutes, Title 30-A, section 4360 takes effect January 1, 2028.
Emergency clause.  In view of the emergency cited in the preamble, this legislation 
takes effect when approved, except as otherwise indicated.
SUMMARY
This bill modifies provisions of law related to housing development and regulation in 
the following ways. 
1. It clarifies requirements related to fire protection in accessory dwelling units. 
2. It modifies provisions governing rate of growth ordinances to require that such an 
ordinance set the number of building or development permits for new residential dwellings 
at 130% or more of the mean number of total permits issued for new residential dwellings 
within a municipality during the 5 years immediately prior.  It also provides that a 
municipality may not enforce certain growth ordinances and that a growth ordinance may 
not require a development permit for affordable housing.  It also establishes requirements 
related to the limit a municipality may place on the number of development permits issued 
per project or per common scheme of development in a designated growth area.
3. It modifies the provision of law that allows certain affordable housing developments 
to exceed municipal height restrictions and establishes a new implementation date by which 
municipalities must apply the requirements with respect to height restrictions as modified 
by this legislation.  It also clarifies that the implementation date established in Public Law 
2023, chapter 192 now applies only to density requirements, not height restrictions.  The 
changes to these implementation dates do not apply until July 1, 2026 for municipalities 
for which ordinances may be enacted by the municipal officers without further action or 
approval by the voters of the municipality and July 1, 2027 for all other municipalities.  
The bill replaces cross-references to the implementation date in current law. 
4. It provides that municipalities may not require minimum subsurface wastewater 
disposal standards for housing structures, affordable housing developments and accessory 
dwelling units other than what is required by the Department of Health and Human Services 
rules for subsurface wastewater disposal. 
5. It modifies provisions of law that place limitations on municipal ordinances that 
establish minimum lot sizes and density requirements for certain residential property. 
6. It clarifies that planning board approval is not needed for accessory dwelling units.  
It also limits the structures in which a municipality is required to allow an accessory 
dwelling unit to a single-family dwelling unit or 2-unit or 3-unit residential structure instead 
of a single-family dwelling unit or multi-unit residential structure as in current law.
7. It provides that a small child care facility or a family child care provider located in 
an area zoned for residential purposes must be subject to the same zoning requirements as 
a single-family dwelling unit. 
8. It clarifies that the provision of law that requires municipalities to allow residential 
units within buildings located in an area zoned for commercial use does not apply to areas 
allowing industrial uses.
9. It creates a grace period from the deadline for updating a municipal ordinance with 
a definition of "subdivision" that is not in compliance with current law by allowing a 
municipality to keep its noncompliant definition in force until January 1, 2028 if the 
municipality files its current noncompliant definition in the applicable county registry of 
deeds by July 1, 2026. 
10. It changes an exception to the law regarding subdivisions for divisions of new or 
existing structures by making the exception applicable to the division of a new or existing 
structure into 5 or more dwelling units instead of 3 or more.