Which building code your Michigan roof job follows

The edition LARA lists for houses today

Michigan writes its residential building code by administrative rule, and the edition is named in the rule. Rule R 408.30500 adopts the 2015 International Residential Code, with listed exceptions, as the Michigan Residential Code. LARA’s Code Books page, read on October 19, 2026, lists the 2015 Michigan Residential Code as the current code for residential buildings. The City of Novi’s published list of codes in effect says the same: the 2015 residential code for detached one- and two-family homes and townhouses of not more than three stories.

So when a roofer talks about “the code,” the text behind that word for a Michigan house is the 2015 edition with Michigan’s amendments. Any page or quote that says the 2021 residential code governs your roof is, on the sources we cite, wrong for now.

The 2025 court order and what we could not confirm

The 2021 International Residential Code was due to take effect in Michigan on August 29, 2025. The rule text on the legal site still carries an “effective until” banner from that replacement. On July 7, 2025, the Michigan Court of Claims issued an order in a case brought by Home Builders Association plaintiffs against LARA, temporarily preventing LARA from implementing the rule set that adopted the 2021 code. LARA’s notice says that while the order stands, the 2015 versions remain valid and in effect.

There are two limits on what we can tell you. The notice on LARA’s site is undated, so we could not confirm whether the case has since ended, been appealed, or produced a different ruling. The notice, linked from the Bureau of Construction Codes home page on October 19, 2026, still listed the 2015 edition. If that changes, LARA will be the first place it shows up.

Why we print no effective date for the 2015 code

Government pages disagree on one point, and we would rather leave it out than choose. LARA’s code books page gives one effective date for the 2015 residential code, while the history line under the rule and the City of Novi’s list give a different one. They may be describing different steps, an original adoption and a later re-issue, but none of the pages says so, and we cannot defend any of the dates. That should not trouble a homeowner, because every source we cite agrees on which edition applies to your permit today.

Which roofing provisions come from the base 2015 text

The roofing rules we cite come from the 2015 International Residential Code as Michigan adopted it, mostly from its roof assemblies chapter.

• Ice barrier, R905.1.2: along the eaves, 24 inches inside the exterior wall line, with an extra 36-inch measurement on slopes of 8:12 or steeper. The ice barrier guide covers it.
• Tear-off, R908.3: replacement removes existing covering down to the deck, with an exception for an adhered ice barrier membrane. See how many layers of shingles are allowed.
• Underlayment, R905.1.1: it must meet listed standards and be labeled, with attachment set by the code’s tables.
• Flashing, R908.5 and R908.6: existing flashings and vents that are part of the assembly are replaced where rusted, damaged or deteriorated.
• Ventilation, R806.2: net free ventilating area of 1/150 of the vented space, with 1/300 allowed in some arrangements.

Each of those is the ICC text. The Michigan rules show no amendments to the ice barrier and tear-off sections, which is a medium-confidence statement, so treat the numbers as the starting point for a conversation with your building department, the office that inspects.

Larger and commercial buildings follow a different code

LARA’s code books page lists the Michigan Building Code, 2021 edition, as effective April 9, 2025, and the Novi list gives it as the code for commercial buildings. The licensing statute defines a “residential structure” as a detached one- or two-family dwelling or a townhouse of not more than three stories above grade plane with a separate means of egress. Our interpretation, which is an inference and carries medium confidence, is that an apartment building of more than two units or a commercial roof falls on the Michigan Building Code side of that line. Roofing contractor licensing rules differ for those buildings, since the maintenance and alteration license covers residential structures. If your building is not a detached house or a townhouse, ask the building department which code it will use. Our flat roof page covers the low-slope questions that tend to come with larger buildings.

What a stayed rule means in practice

A court stay is not a repeal. The order, as LARA describes it, prevents the agency from implementing the 2021 rule set for now, and the 2015 rules continue because nothing has replaced them. If the order is lifted or the case is decided against the builders, the 2021 code could take effect on a date LARA announces, and a job quoted under one edition could be permitted under another. We have no source on how LARA would treat jobs already under contract, so we will not guess. The sensible protection is a quote that names the edition it follows and a permit application that is filed while the edition is known.

Homeowners rarely read code books, and nothing here asks you to. It is enough to know the question exists, so that a salesperson repeating an out-of-date web page does not set the terms of your roof.

What to do before you sign a roofing quote

Start with the question that costs nothing, which is which code edition the quote follows. A company working from the 2015 text can answer in a sentence. A company that names the 2021 code has either read something we have not or has repeated a page that skipped the court order, and you can ask it to show you where LARA says so.

Next, open LARA’s Code Books page yourself before work starts, and look at the residential entry. The edition listed there on the day you sign is the one that matters, not the one we saw on October 19. If the page has changed, ask the roofer to update the quote’s code references before you accept it.

Last, code is enforced locally. Roofing is not on the state’s list of permit exemptions, and the building department in your city or county decides whether a shingle replacement needs a permit. Do you need a permit to replace a roof in Michigan covers that side, and the roof replacement page shows how a job fits together. This situation may change, and if it does, this page will be revised.