Regional Building Codes for Factory-Built Structures

The bill provides that after the state housing board (board) adopts rules about any activity required to undertake or complete the construction or installation of a factory-built nonresidential structure, a factory-built residential structure, or a factory-built tiny home (factory-built structure), the state plumbing board, the state electrical board, and the state fire suppression administrator do not have jurisdiction over and their rules do not apply to a factory-built structure.

On or before July 1, 2026, the advisory committee on factory-built structures (advisory committee) is required to develop regional building codes for factory-built structures and implementation requirements and submit the recommended codes to the board.

On or before July 1, 2026, the board must adopt rules:

• Implementing regional building code recommendations from the advisory committee that account for local climatic and geographic conditions for the construction and installation of factory-built structures, which supersede any conflicting ordinance, code, regulation, or other law of a local government unless the local government adopts the rules of the board;
• Covering the implementation requirements developed by the advisory committee, including authorizing a local government certified by the division of housing (division) to perform inspections of factory-built structures on behalf of the division and registration, responsibility, and accountability requirements for a manufacturer, installer, seller, or general contractor who develops the installation site or completes the construction of a factory-built structure at the installation site;
• Covering electrical, plumbing, or fire suppression activity required to undertake or complete the construction or installation of a factory-built structure;
• Allowing the division to contract for third-party review and approval of a final design plan for a factory-built structure on behalf of the division;
• Allowing the division to create a process for vetting and approving the ability of a third party to review and approve a final design plan for a factory-built structure on behalf of the division; and
• Requiring the division to cause an audit to be performed on a third party that reviews and approves design plans.

On or before July 1, 2026, the advisory committee is required to conduct a study on behalf of the division about whether the international building code or residential code standards that apply to site requirements should be incorporated into state statutes and rules and to determine whether the state should regulate non-factory-built components that are connected to a factory-built structure at the installation site and are currently under local jurisdiction. The division is required to deliver the study to the board when complete.

A county or municipality may not:

• Enact a regulation that excludes factory-built structures and manufactured homes from the county or municipality;
• Impose more restrictive standards on factory-built structures and manufactured homes than those that the county or municipality applies to site-built homes in the same residential zones in the county or municipality; or
• Enact or enforce a regulation, law, or ordinance affecting the installation or construction of a factory-built structure or manufactured home.

A county or municipality may:

• Enact land use regulations to the extent that the regulations are applicable to existing housing or structures or new site-built housing in the county or municipality; and
• Enact a building code provision for unique public safety requirements unless the provision applies to a factory-built structure or manufactured home.

A county or municipality must comply with the requirements established by the division for factory-built structures and by the United States department of housing and urban development for manufactured homes.

The bill requires the state treasurer to transfer $600,000 on July 1, 2025, from the innovative housing incentive program fund to the building regulation fund.

(Note: This summary applies to this bill as introduced.)