Indiana HVAC Legislation, Codes, and Guidelines

State-Level HVAC Building Codes in Indiana

In Indiana, building codes—including those governing heating, ventilation, and air conditioning (HVAC) systems—are established through the Indiana Administrative Code (IAC) under Title 675. These codes are developed and maintained by the Fire Prevention and Building Safety Commission. The state adopts model codes from the International Code Council (ICC) and incorporates specific Indiana amendments to address local requirements, climate conditions, and safety standards.

For residential construction, the state enforces the Indiana Residential Code, which is based on the International Residential Code (IRC). For commercial and other Class 1 structures, the state utilizes the Indiana Mechanical Code, which is based on the International Mechanical Code (IMC), alongside the Indiana Building Code and the Indiana Fuel Gas Code. Energy efficiency requirements for HVAC systems are governed by the Indiana Energy Conservation Code, which incorporates standards such as ASHRAE 90.1 for commercial applications.

Compliance with these codes is mandatory for new construction, additions, and major alterations. Enforcement is primarily handled by the Indiana Department of Homeland Security (IDHS) through its Division of Fire and Building Safety, in conjunction with local municipal and county building departments that oversee permitting and inspections.

Primary State Agencies

Resources to Learn More

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

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.