Montana building code

How Montana adopts building codes

Mont. Code Ann. §§ 50-60-203, -205, -301, -302, -304

• Montana Department of Labor and Industry, by rule. The department may adopt by reference nationally recognized building codes in whole or in part, except as provided in subsections (5) and (6), and may adopt rules more stringent than those contained in national codes.¹
• Adopted rules constitute the state building code. The rules, when adopted as provided in parts 1 through 4, constitute the "state building code" and are acceptable for the buildings to which they are applicable.¹
• State code and state enforcement apply where no local code is adopted. If a county, city, or town does not adopt a building code as provided in 50-60-301, the state building code applies within the county, city, or town and the state will enforce the code in these areas.²
• Local adoption is optional. The local legislative body of a county, city, or town may adopt a building code to apply to the county, city, or town by an ordinance or resolution, as appropriate…³
• Local enforcement requires department certification. …the code enforcement program has been certified by the department as in compliance with applicable statutes and department certification rules…⁴
• City enforcement stops at city limits. A city or town that adopts a building code under this chapter may enforce its building code only within the incorporated limits of the city or town.⁵
• Rules require a public hearing. …a rule, amendment, or repeal of the state building code is a matter of significant public interest for purposes of 2-3-103 and may not take effect until after a public hearing by the department.⁶
• No required sprinklers in one- and two-unit homes. …a requirement for the installation of a fire sprinkler system in a single-family dwelling or a residential building that contains no more than two dwelling units…¹
• No required solar or EV equipment. …a requirement that buildings be constructed to have solar panels or wiring, batteries, or other equipment for solar panels or electric vehicles.¹
• 2021 codes, local effective date September 23, 2022. NEW BUILDING CODES (2021) TAKE EFFECT SEPTEMBER 23, 2022.⁷

Applies to

Excludes residential buildings under five dwelling units, farm and ranch buildings and private owner-use garages or storage structures unless locally adopted⁸

Can local rules be stricter?

Except as provided in subsection (2)(b), a county, city, or town may not adopt or enforce a building code that is more stringent than the building code adopted by the department or as required by state law.³

What local governments may change

Mont. Code Ann. §§ 50-60-301(2), 37-45-204

• Statewide; local amendments not allowed. Except as provided in subsection (2)(b), a county, city, or town may not adopt or enforce a building code that is more stringent than the building code adopted by the department or as required by state law.³
• Voluntary energy incentives may exceed the state code. New construction is not required to meet local standards that exceed state energy conservation standards unless the building contractor elects to receive a local incentive.³
• Local governments may not license contractors for the same purpose. A political subdivision of the state may not require or issue any registrations, licenses, or bonds for the same or a similar purpose.⁹

For permits, exemptions and owner-builder rules, see Montana building permits. To compare editions across states, see the code adoption map.