Montana HVAC Legislation, Codes, and Guidelines

Montana HVAC Building Codes and Legislation

The State of Montana enforces a statewide building code system that incorporates several model codes by reference. These codes are amended at the state level to address specific regional needs, such as snow loads and energy efficiency. For HVAC systems, the state has adopted the 2021 editions of the International Mechanical Code (IMC) and the International Fuel Gas Code (IFGC), along with the 2021 International Energy Conservation Code (IECC).

Regulatory Authority and Adoption

The primary agency responsible for establishing and enforcing these standards is the Montana Department of Labor & Industry (DLI), specifically through the Building Codes Program within the Business Standards Division. The state adopts these codes through the Administrative Rules of Montana (ARM), specifically under Title 24, Chapter 301. While the state sets the baseline, local jurisdictions (cities, counties, or towns) may be certified to enforce these codes locally. In areas without a certified local program, the state's Building Codes Program serves as the authority having jurisdiction.

Resources to Learn More

Select a County Below to Learn More About That Jurisdiction in Montana

Permit rules operate within the above structure but can be nuanced at the county or municipal level. Select your local area below for specific ordinances, local codes, and direct links for your locality Building Department.