Which residential code applies to Michigan foundation work, 2015 or 2021

The short history of a paused update

Michigan’s residential code is a version of the International Residential Code, amended by state rules. LARA’s code-books page lists the “2015 Michigan Residential Code” as the current code, effective February 8, 2016. The page also lists a 2021 Michigan Building Code, effective April 9, 2025, so the commercial side moved on while the residential side did not.

A code consulting firm’s notice, which we treat as medium confidence because it is third-party, reported that LARA’s rules adopting the 2021 International Residential Code with Michigan amendments were filed with the Secretary of State on May 1, 2025 and were scheduled to take effect on August 29, 2025. That is where many pages stop, and it is why a lot of contractor sites say the 2021 code is in force.

It is not, according to LARA. A LARA notice says that on July 7, 2025 the Court of Claims, in a case brought by the Home Builders Association and others, issued an order temporarily preventing LARA from taking additional steps to implement the rule sets updating the Michigan Residential Code and the residential energy chapter. LARA says the 2015 versions “remain valid and in effect” while the stipulated order remains in place. The notice is still linked from LARA’s Bureau of Construction Codes page as we write, on October 19, 2026. We could not tell whether the order has been lifted since July 2025, so read this guide as accurate to the LARA notice we read and confirm with your city.

Cities say the same thing

You do not have to take a state notice on faith, because the people who enforce the code say so on their own pages. Troy’s codes page lists the 2021 Michigan Building Code, says LARA agreed to pause the 2021 residential code, and says the 2015 Michigan Residential Code and residential energy chapters remain in effect. Westland lists the 2015 Michigan Residential Code among the standards it enforces. Sterling Heights prints a residential plan review checklist headed “Based on The Michigan Residential Code 2015”.

All ten cities we researched, from Detroit to Westland, are listed as local enforcers for building, electrical, mechanical and plumbing on LARA’s Statewide Jurisdiction List revised October 6, 2026. That means the city itself reviews and inspects your project, so the city is the authority to ask about the edition.

A warning about the rule pages

If you look up Michigan’s rules on a public legal site, be careful. Cornell’s Legal Information Institute shows R 408.30509 with a history note of 2025 MR 10, effective August 29, 2025, and text citing newer section numbers. That matches the paused 2021 rule set. A rule number on a legal-text site is therefore not proof that the 2021 code applies. Quote the LARA statement, not a rule number.

What we could and could not read

We read the base 2015 International Residential Code text from the ICC for the sections below. We also read the Michigan amendments to the frost depth, the permit exemptions and the climate table. We could not open the Michigan rules that might amend the rest of chapter 4, so whether Michigan alters the drainage, waterproofing or under-floor provisions is unverified. Wherever this site says “the 2015 code says”, it means the base text, and we say when a Michigan rule changes it. Ask LARA’s Bureau of Construction Codes if a detail matters for your job.

What the 2015 provisions mean for foundation work

Permits. Section R105.1 says any owner or authorized agent who intends to construct, enlarge, alter, repair, move or demolish a building or structure, or install or repair plumbing, gas, mechanical or electrical systems, must first apply to the building official and obtain the permit. Michigan’s R 408.30505 rewrites the exemptions: one-story detached accessory structures up to 200 square feet, fences up to 7 feet, retaining walls up to 4 feet, sidewalks and driveways not more than 30 inches above grade, painting, tiling and cabinets and the like. Foundation repair, underpinning, waterproofing and crawl space work are not on the exemption list, which is our reading. The base code also says ordinary repairs do not include cutting away of any wall, removal or cutting of a load-bearing support, or replacement of drainage piping. We could not confirm that the Michigan rewrite keeps that sentence, so treat it as indicative. The permits by city guide shows what ten cities print.

Frost depth. Michigan amends the footing rule so that all exterior footings and foundation systems extend 42 inches below actual grade, and the building official may modify the depth on evidence of freezing degree days, soil type, ground water, snow depth, exposure or other conditions. That is a footing rule. See Michigan frost depth.

Wall design. R404.1.1 requires engineered design where walls are subject to hydrostatic pressure or support more than 48 inches of unbalanced backfill. Read the engineer first guide for what that means in practice.

Drainage and dampproofing. R405 requires drains around foundations that retain earth and enclose habitable or usable space below grade, with an exception for well-drained soils. R406 calls for dampproofing of below-grade walls and waterproofing where a high water table or other severe soil-water condition is known to exist. Both are written for new work. Whether they oblige the owner of an older home to add a drain is our inference: they do not, on their face. See basement waterproofing.

Crawl spaces. R408 gives two routes, a vented space or an unvented one built to R408.3. See crawl space encapsulation and the code.

Inspections. R109.1.1 puts the foundation inspection after trenches are excavated and forms and reinforcing are in place, before concrete is placed. It is written for new foundations. Whether a city applies it to underpinning footings is the city’s call.

The permit clock

Michigan’s Stille-DeRossett-Hale Single State Construction Code Act requires the enforcing agency to examine a building permit application and grant or deny it within 10 business days, or 15 for an unusually complicated building. Failure to act within that time counts as a denial that can be appealed. Warren’s page adds that Michigan law since 2004 requires communities to adopt and enforce the Michigan Building Code and the Michigan Residential Code. Both facts help you hold a slow permit counter to a schedule.

How to confirm your code edition in five minutes

1. Open your city’s building department page and look for a “codes currently in effect” list. Troy has one.
2. If there is none, email or call the building office and ask which edition of the Michigan Residential Code it enforces for a repair to an existing house.
3. Ask if a foundation, waterproofing or crawl space job needs a permit at your address, and which form applies.
4. Ask your contractor to name the code section behind any statement that something is “required by code”. We found that the dehumidifier and 12 to 20 mil liner claims for crawl spaces are not in the 2015 text; see the crawl space guide.

What this guide does not say

It does not say that foundation repair always needs a permit, or never does. We found no Michigan state page that says either in plain words. It does not say your contractor is wrong if they cite the 2021 code, only that LARA’s page and three cities say 2015 applies today.