Housing Legislation - L.D. 1829

LD 1829, An Act to Build Housing for Maine Families and Attract Workers to Maine Businesses by Amending the Laws Governing Housing Density

(Signed by Governor Mills on Friday, 06/20/2025)

LCRPC is just learning about this legislation and its potential impacts on municipal ordinances. This bill appears to build off LD 2003 changes and attempts to remove additional barriers from getting accessory dwelling units (ADUs) constructed. This summary was quickly produced and may be amended as more information comes forward.

We anticipate having more insight for you as rulemaking takes place; however, it appears the following changes will be made:

Fire suppression sprinklers are not required for an accessory dwelling unit unless the accessory dwelling unit is within or attached to a structure of more than 2 dwelling units, including accessory dwelling units.

A municipality may not enact rate of growth ordinances that limit residential development in designated growth areas.

Outside the shoreland zone, 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.

Upon receipt of written verification from a local plumbing inspector that a housing structure meets the requirements of MRSA $4364 (LD 2003 state statute), additional review or documentation by a municipality related to waste and wastewater requirements before issuing a certificate of occupancy is prohibited.

Updates use allowances by stating that for any area in which residential uses are allowed, including as a conditional use, a municipality shall allow at a minimum:
- Three dwelling units, attached or detached, including accessory dwelling units, per lot; and
- Four dwelling units, attached or detached, including accessory dwelling units, per lot if the lot is located in a designated growth area, as identified in a comprehensive plan or served by a public, special district or other centrally managed water system and a public, special district or other comparable sewer system.
- A municipality may allow more units than the minimum number required by this subsection.

Updates lot size and density allowancesfor private property by applying to any area in which residential uses are allowed, including as a conditional use.
- If a lot is located in a designated growth area and is served by public water and public sewer, a minimum lot size requirement may not exceed 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.

If a lot is located outside a designated growth area and in an area served by public water and public sewer, a minimum lot size requirement may not exceed 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.

If a lot is located in a designated growth area but is not served by public sewer a minimum lot size requirement may not exceed the minimum lot size required by Title 12, chapter 423-A (a quick read looks like 20,000 square feet)

If 4 or fewer dwelling units have been constructed on a lot as a result of the allowances under this section, the lot is not eligible for any additional increases in density, unless more units are allowed by the municipality.

A municipal ordinance may not establish dimensional requirements for multiple units allowed by this section that are greater than dimensional requirements required for single-family dwelling units. As used in this subsection, “dimensional requirements” means requirements that govern the size and placement of structures, including building height, lot area, minimum frontage, lot depth and setbacks.

A municipality may not require planning board approval for 4 or fewer dwelling units within a structure.

An accessory dwelling unit must be allowed on a lot that does not conform to the municipal zoning ordinance if the accessory dwelling unit does not further increase the nonconformity.

A municipality shall allow the construction or occupancy of an ADU on a lot even if the owner of the lot where the ADU is located does not reside in a dwelling unit on that lot.

The municipal reviewing authority and the municipal body hearing zoning appeals shall attend a training on land use planning offered by a state agency or a statewide association representing municipalities or a regional council or municipality within 180 days of appointment. Current board members need to take a training within 180 days of the effective date of this Act.

Subdivision: Changes the definition to include the division of a new structure or structures on a tract or parcel of land into 5 (used to be 3) or more dwelling units within a 5 year period.

Implementation deadline for town-meeting form of government is July 1, 2027. Town council form of government is July 1, 2026.