allowing accessory dwelling units to be built within or attached to certain non-conforming structures.

The bill title and page headers were updated from 'AS AMENDED BY THE SENATE' to 'VERSION ADOPTED BY BOTH BODIES,' indicating the bill reached final adoption. No changes to the actual policy text, requirements, or scope of the bill were made.

The Senate removed the provision repealing RSA 674:73 (the existing state law on detached accessory dwelling units). This preserves the current state ADU framework rather than eliminating it, meaning both the old and new provisions will coexist.

The effective date section was renumbered from section 4 to section 3 due to the removal of the repeal provision. The 60-day effective period itself was unchanged.

Structures containing an ADU approved and built after July 1, 2025 now receive protection from future zoning changes under RSA 674:39, II, as long as they meet the time periods for active/substantial development and substantial completion defined in RSA 674:39, I.

A new subsection (c) clarifies that converting an existing structure to an accessory dwelling unit does not constitute a 'change of use' under state or local zoning law, meaning the structure keeps its status as a preexisting nonconforming structure and is not penalized for adding an ADU.