SB 532: Revise county zoning to allow accessory dwelling units - Montana

SB0532_X(3).pdf → SB0532_X(4).pdf · 4 edits

MODERATE

The bill was amended to streamline the review process for adding accessory dwelling units (ADUs) to properties with existing wastewater systems, reducing the review period to 15 days. A new section was added to clarify that counties cannot adopt regulations that are less permissive than the state's new ADU provisions. Additionally, the bill introduced new definitions for 'accessory dwelling unit' and established specific criteria for qualifying for expedited reviews, including a requirement for a certificate of subdivision approval.

Scope change

The bill's scope was expanded to explicitly allow counties to adopt more permissive regulations than the state, and it now includes specific definitions and eligibility criteria for expedited ADU reviews.

REQUIREMENT

Added a 15-day expedited review timeline for ADUs on parcels with existing public water and wastewater services.

Added a provision prohibiting counties from adopting regulations that are less permissive than the state's ADU rules.

Removed the requirement for subsurface on-site wastewater treatment systems in the expedited review context.

DEFINITION

Added new definitions for 'accessory dwelling unit' and criteria for qualifying for expedited reviews.

SB0532_X(2).pdf → SB0532_X(3).pdf · 7 edits

MODERATE

The bill was amended to streamline the text by removing redundant numbering and clarifying that counties cannot impose specific restrictive rules on accessory dwelling units. The changes ensure that counties cannot require matching exterior designs, owner occupancy, familial relationships between residents, or impact fees, while also prohibiting stricter development standards like minimum lot sizes or setbacks compared to the main home. Additionally, the bill added a provision allowing homeowners to deviate from subdivision approvals if they connect to existing municipal water or sewer facilities, simplifying the process for homes with existing infrastructure.

Scope change

The scope of prohibited county regulations was clarified and expanded to explicitly list specific restrictions (like design matching and impact fees) that counties are forbidden from enforcing, ensuring greater flexibility for accessory dwelling unit construction.

REQUIREMENT

Removed redundant numbering and reorganized the list of prohibited county regulations to improve clarity.

Clarified that counties cannot require accessory dwelling units to match the exterior design, roof pitch, or finishing materials of the main single-family dwelling.

Prohibited counties from requiring that the main home or accessory unit be occupied by the property owner.

Banned requirements for a familial, marital, or employment relationship between the occupants of the main home and the accessory dwelling unit.

Explicitly forbade counties from assessing impact fees on the construction of accessory dwelling units.

Prohibited counties from imposing stricter development standards (such as minimum lot sizes or setbacks) for accessory dwelling units than those applied to the main single-family dwelling.

Added a new provision allowing a person to deviate from subdivision approval if they connect to existing municipal, county, or regional water and sewer facilities, removing the need for new approval in such cases.

SB0532_3(4).pdf → SB0532_X.pdf · 5 edits

MODERATE

This bill updates Montana's zoning laws to mandate that counties allow at least one accessory dwelling unit (ADU) by right on single-family lots. It strictly limits what counties can require, such as prohibiting fees for parking, design matching, or owner-occupancy, while allowing a modest application fee of up to $250. The bill also clarifies definitions for ADUs and establishes a termination date for the new regulations.

Scope change

The bill expands the scope of county zoning authority by mandating the approval of ADUs and restricting counties from imposing certain barriers to their creation.

REQUIREMENT

Counties must allow at least one ADU by right on single-family lots.

Counties are prohibited from requiring additional parking, matching exterior designs, or owner-occupancy for ADUs.

FISCAL

Counties are limited to a one-time application fee of up to $250 per ADU.

DEFINITION

New definitions clarify what constitutes an ADU and the meaning of 'by right' approval.

TIMELINE

The bill includes a termination date for the new ADU regulations.

SB0532_2(13).pdf → SB0532_3.pdf · 2 edits

MINOR

This bill amends the definition of an accessory dwelling unit to explicitly include connections to public water and wastewater services, ensuring these units are treated consistently with other developments. It also restructures the list of prohibited county restrictions by adding lettered sub-points to clarify that counties cannot impose specific design, occupancy, or development standards that are more restrictive than those for the main single-family home.

Scope change

The scope of the bill's protections was expanded to explicitly cover public utility connections, and the clarity of restrictions on county regulations was improved through structural formatting.

DEFINITION

Added 'PUBLIC WATER AND WASTEWATER SERVICE' to the definition of an accessory dwelling unit, clarifying that units connected to public utilities are included under the bill's protections.

REQUIREMENT

Reformatted the list of prohibited county actions (such as requiring specific designs or occupancy rules) by adding lettered sub-points (A through H) to improve readability and legal clarity.

SB0532.002.004_combo_final-not condensed.pdf → SB0532_2(10).pdf · 4 edits

MODERATE

The bill was renumbered to SB0532.2 and updated to reflect the 69th Legislature in 2025. The text was cleaned up to remove redundant parenthetical references (e.g., '(b)(a)') while retaining the original legal restrictions. A new definition for 'accessory dwelling unit' was added, specifying it must be of greater square footage than the main home and include specific living facilities. The bill also expanded the definition of 'by right' to include exemptions from various discretionary zoning actions beyond just public hearings.

Scope change

The scope of the bill remains focused on regulating accessory dwelling units and subdivision approvals, but the definition of an ADU has been narrowed by adding a square footage requirement relative to the primary dwelling.

DEFINITION

Added a new definition for 'accessory dwelling unit' requiring it to be of greater square footage than the single-family dwelling and to include its own cooking, sleeping, and sanitation facilities.

Expanded the definition of 'by right' to explicitly exclude the need for variances, conditional use permits, special permits, or other discretionary zoning actions.

TECHNICAL

Removed redundant parenthetical numbering (e.g., '(b)(a)') throughout the text to improve readability and consistency.

Updated the bill header to reflect the 69th Legislature (2025) and changed the bill number to SB0532.2.

SB0532_2(9).pdf → SB0532.002.004_combo_final-not condensed.pdf · 4 edits

MODERATE

This bill amends state laws to regulate accessory dwelling units (ADUs) by clarifying size limits, removing requirements for owner occupancy or familial relationships, and prohibiting counties from imposing stricter rules than those set by state law. It also updates the definition of ADUs to include units connected to public water and wastewater services.

Scope change

The bill expands the scope of ADU regulations by removing barriers to entry (such as owner-occupancy requirements) and standardizing rules across counties to prevent local restrictions that hinder ADU development.

REQUIREMENT

Removed the requirement that the owner must occupy the single-family dwelling or the ADU.

Removed the requirement that occupants of the ADU must have a familial, marital, or employment relationship with the main house occupants.

Clarified that counties cannot set building standards (like setbacks or lot sizes) for ADUs that are more restrictive than those for the main single-family home.

DEFINITION

Updated the definition of an ADU to explicitly include units connected to public water and wastewater services.

SB0532_1(5).pdf → SB0532_2.pdf · 3 edits

MINOR

The bill was renumbered from SB 532.1 to SB0532.2 and updated its title to include a termination date. The core policy regarding Accessory Dwelling Units (ADUs) remains largely unchanged, but the text was reorganized to clarify that counties can charge a review fee up to $250 per unit. A new provision was added to Section 2, allowing deviations from subdivision certificates if a property connects to municipal water or sewer, streamlining the process for ADUs in areas with public utilities.

Scope change

The bill's scope regarding ADU regulations remains the same, but the applicability of Section 2 is expanded to include specific deviations for properties connecting to public water and sewer systems.

TECHNICAL

The bill number was changed from SB 532.1 to SB0532.2, and the title was updated to explicitly mention a termination date.

REQUIREMENT

A new clause was added to Section 2 allowing a person to deviate from a subdivision certificate of approval without approval if the deviation is solely for connecting to municipal or county water and/or sewer districts.

The text regarding county fees was restructured to clearly state that counties may require a one-time application fee of up to $250 per ADU in addition to usual building fees.

LC0705.pdf → SB0532_1.pdf · 3 edits

MINOR

The bill was renumbered from LC 0705 to SB 532 and updated with new sponsor names. The substantive policy content regarding accessory dwelling unit regulations remains unchanged, including rules on size limits, parking requirements, design matching, and occupancy restrictions.

TECHNICAL

The bill number was changed from LC 0705 to SB 532, and the list of sponsors was updated to include F. Mandeville, D. Zolnikov, J. Fuller, C. Glimm, G. Hertz, and K. Bogner.

The header text was updated from 'Authorized Print Version - LC 0705' to 'Authorized Print Version - SB 532'.

Minor formatting adjustments were made to the spacing and indentation of the text, but no legal language was altered.

Revise county zoning to allow accessory dwelling units

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