Oklahoma moved its building and mechanical codes to the 2024 editions in September 2026, kept its commercial energy code on the 2006 edition, and its two largest cities still enforce 2018 codes. Which edition governs is the first question on any Oklahoma project.

The same services in every state

Adicot provides the same engineering services in every state it is licensed in, for industrial, commercial and multi-family buildings of any size. What changes from state to state is the code the work is held to.

Cooling Load/Heat Load Calculations: room-by-room loads worked with ASHRAE methods, with ventilation rates to the adopted code
Energy Code Compliance: the building modeled and compliance demonstrated on performance where the code allows it, in the format the plan reviewer expects

Both are sealed by a professional engineer licensed in the state. Get a Quote to see the fee.

We work on industrial buildings, commercial buildings from offices and retail to restaurants and clinics, and multi-family buildings.

The codes in force in Oklahoma

The Oklahoma Uniform Building Code Commission adopts the statewide minimum codes. As of October 2026:

Mechanical: the 2024 International Mechanical Code with Oklahoma amendments, in effect since September 14, 2026. It replaced the 2018 edition.
Building: the 2024 International Building Code, in effect since September 14, 2026.
Energy: the 2006 International Energy Conservation Code with state amendments, mandatory statewide. The commission's new 2024 rules still point to it. A commission committee is reviewing the commercial provisions of the 2021 and 2024 IECC; no adoption date has been set.

What is particular to Oklahoma

Oklahoma City and Tulsa. Oklahoma City lists the 2018 building and mechanical codes and the 2009 IECC. Tulsa lists the 2018 codes and has scheduled the 2024 codes for January 1, 2027. We confirm the edition with the city's building department before any calculation starts.

Climate. Most of Oklahoma is climate zone 3A, humid, where cooling and dehumidification drive the design. Fifteen northern counties, including Kay, Garfield, Osage and Washington, are zone 4A on the 2021 climate map, and the panhandle counties of Beaver, Cimarron and Texas are dry zone 4B. The 2006 energy code uses the older map, on which those fifteen counties are 3A.

Projects in Oklahoma

Cooling load calculations for utility buildings in Snyder, 2023 (see substation and utility control buildings)