Welcome to 2025! As we anticipate the opportunities, challenges, and new experiences that await us, it is important to note a significant development that affects everyone: the implementation of the new Michigan Commercial Energy Code.
Similar to the Building Code, the State of Michigan sets a uniform commercial energy code that must be followed throughout the state. The advantage of having a consistent code is that it simplifies design and construction collaboration among engineers, architects, and contractors. With a shared understanding and adherence to a uniform code, there's no confusion about whether they're following the Detroit Energy Code, the Wayne County Energy Code, or the State of Michigan Energy Code, etc.
***ASHRAE 90.1 - 2019 is widely recognized as the gold standard for energy efficiency in commercial buildings.
A downside of a uniform code is that municipalities aiming for more aggressive carbon and energy standards can't enforce stricter measures. The good news for sustainable design is that commercial buildings designed to the new Michigan Commercial Energy Code are expected to have roughly 12% lower energy usage than buildings designed to the outgoing code.
The Michigan Commercial Energy Code was last updated in 2017, and is currently based on the 2015 International Energy Conservation Code (IECC) and ASHRAE Standard 90.1-2013. The Michigan Commercial Energy Code applies to commercial buildings only, including large multifamily buildings. The energy standards for single family homes are covered in the Michigan Residential Code (MRC).
Although slightly confusing, the Michigan Commercial Energy Code is comprised of two separate standards. ASHRAE 90.1 contains many rules for designing energy efficient buildings, but does not have any "teeth" that would allow it to be enforceable as a legal code. The IECC, with "Code" in its very title, is a model code. Similar to how the model building code is adopted into the Michigan Building Code, the IECC contains rules for designing energy efficient buildings and the "teeth" that allow those rules to be enforced.
***Additionally, the new code places a greater emphasis on energy-efficient lighting systems, including the use of 100% LED technology and advanced lighting controls.
To comply with IECC for commercial buildings, you have basically two options: either follow the rules contained in the "non-teeth" sections of the IECC itself, or adhere to the rules outlined in ASHRAE 90.1. The Michigan Commercial Energy Code says, (paraphrased) "you must follow both IECC and ASHRAE 90.1".
This means that adhering to ASHRAE 90.1 also ensures compliance with the IECC, thereby meeting Michigan's code requirements.
Starting April 22, 2025, the Michigan Commercial Energy Code will require:
So which buildings need to follow the new code? It's all based on your permit date. If your building is permitted before April 22, you're locked into the old code. Permit after April 22? New code. As always, these codes apply to new construction only.
***Existing buildings are not required to modernize themselves to meet the new Michigan Energy Code, unless a deep renovation of the building is performed.