Wisconsin HVAC Legislation, Codes, and Guidelines

State Statutes and Codes Adopted

Wisconsin utilizes a hybrid approach to building codes, maintaining its own administrative code chapters that incorporate and amend national model codes. As of October 1, 2025, Wisconsin transitioned to the 2021 editions of the International Code Council (ICC) suite for commercial and multi-family residential buildings, with specific state-level amendments known as "Wisconsinisms."

• Commercial and Multi-Family Buildings: These are governed by the Wisconsin Commercial Building Code, found in Chapters SPS 361–366 of the Wisconsin Administrative Code. Chapter SPS 364 specifically addresses heating, ventilating, and air conditioning (HVAC) systems by adopting the International Mechanical Code (IMC) with Wisconsin-specific modifications.
• One- and Two-Family Dwellings: These are regulated under the Wisconsin Uniform Dwelling Code (UDC), found in Chapters SPS 320–325. HVAC requirements for these dwellings are specifically detailed in Chapter SPS 323.

Primary State Agencies

The primary agency responsible for the development, adoption, and oversight of building, fire safety, and energy efficiency codes in Wisconsin is the Department of Safety and Professional Services (DSPS). Within the DSPS, the Division of Industry Services (DIS) manages the programs for commercial buildings and one- and two-family dwellings, coordinating with local certified municipalities that handle plan reviews and inspections.

Resources to Learn More

• Wisconsin DSPS Commercial Building Code Program
• Wisconsin DSPS Uniform Dwelling Code (UDC) Program
• Wisconsin Administrative Code Chapter SPS 364 (Commercial HVAC)
• Wisconsin Administrative Code Chapter SPS 323 (Residential HVAC)
• Calculate a HVAC Replacement Project in Wisconsin
• Wisconsin Hvac Contractor Licensing Requirements
• Find Hvac Contractors in Wisconsin