Michigan enforces the 2021 IECC commercial

Record of adoption

In force since

Apr 22, 2025

Legal citation

Mich. Admin. Code, Construction Code Part 10a (R 408.31087 et seq.)

Adopted by

Department of Licensing and Regulatory Affairs (LARA), Bureau of Construction Codes

Second reading

Agreed Oct 19, 2026

Applies

Statewide

Also called

Part 10a, Michigan Uniform Energy Code (commercial)

Rules allow either ASHRAE 90.1 or the Michigan-amended 2021 IECC; the 90.1 year (2019) is from DOE only. Filed Dec 23, 2024.

Coming next

• Edition not knownLead only
  No date yetIn developmentMich. Admin. Code, Construction Code Part 10a

  Part 10a was on the agenda of the May 21, 2026, advisory meeting.

How Michigan adopts the IECC commercial

• Agency rule
• The legislature reviews the rules and can block them
• The legislature sets the update schedule

LARA rulemaking with advisory meeting, JCAR review and filing; the commercial energy code is on the statutory 3-year update cycle.

Cycle. Statute: at least every 3 years to coincide with the national cycle.

How it was checked

Verified

Two separate readings of the state’s own record agree, and the passage is on file word for word.

Read twice: a second, blind reading of the state’s record agreed with the first on Oct 19, 2026.

The state’s record was last read on Oct 19, 2026, from two source pages.

Evidence 2 sources

Sources for the record itself come first, the state’s own records ahead of others. A label marks a source about something else, such as an exception. A source marked secondary is not the state’s own record.

• “2021 Michigan Commercial Energy Code-Current Code-Effective April 22, 2025”

• “the 2021 edition of the International Energy Conservation Code (IECC)”

  “will become effective on April 22, 2025”

Tracker cross-checks

Code adoption trackers are a cross-check. They are not Michigan’s own record.

• DOE’s energycodes.govCross-checkAgrees with the record

  Commercial: 2021 IECC and ASHRAE 90.1-2019; Effective Date 04/22/2025

  energycodes.gov (opens in a new tab)Read Oct 17, 2026

• BCAP’s code status pageCross-checkDoes not agree with the record

  Commercial: 2021 Michigan Uniform Energy Code based on 2021 IECC and ASHRAE 90.1-2019, effective 3/1/2024

  bcapcodes.org (opens in a new tab)Read Oct 17, 2026

Related pages

• See Michigan’s IECC commercial on the map
• IECC commercial adoption in every state
• All six codes in Michigan

Other codes in Michigan

• NEC2023 NECVerified
• IBC2021 IBCVerified
• IRC2015 IRCVerified
• IFCAnother model codePartial
• IECC residential2015 IECCVerified