StateDataIndex

State Guide · Verified 2026

Deck Construction Permits in Michigan

Permit typically required in Michigan

The only exception is a small freestanding platform 200 sq ft or smaller and no more than 30 inches above grade that is not attached to the house (IRC R105.2); any attached or elevated deck needs a permit. Michigan is stricter: a freestanding deck must also be at least 36 inches from any structure to qualify.

The Building Code in Michigan

Michigan Residential Code (MRC), 2015 IRC based, Bureau of Construction Codes; 2021 MRC update delayed by court order

The Michigan Bureau of Construction Codes, within LARA, administers the MRC statewide under the Construction Code Act of 1972; municipalities can adopt stricter standards but cannot go below the state minimum. Adoption of the 2021 MRC and 2021 IECC was scheduled to take effect August 29, 2025, but was delayed by a July 7, 2025 court order, so the 2015 MRC remained the operative statewide code as of this research. Under 2015 MRC R105.2, a deck is exempt from a building permit only if it meets all of the following: total area 200 square feet or less, no more than 30 inches above grade at any point, not attached to the dwelling, at least 36 inches away from the dwelling or any accessory structure, and does not serve a required ingress or egress door.

Quick Facts

Statewide 5-part exemption test
Under 200 sq ft, under 30 in above grade, not attached, at least 36 in from any structure, no exit door served
Current code edition
2015 MRC; 2021 update delayed by a July 7, 2025 court order
Frost depth (MRC R403.1.4)
Minimum 42 in below grade statewide, deeper in northern regions
Regional frost depth range
42 in (Detroit, Grand Rapids) to 48-60 in in the Upper Peninsula
Snow load range
20-30 psf in Southeast Michigan to 70+ psf in the Upper Peninsula, over 90 psf in the Keweenaw Peninsula
Design wind speed
115 mph ultimate design speed statewide (Risk Category II)

A five-part test, not a simple size or height rule

Most states exempt a deck based on size and height alone. Michigan's exemption requires all five conditions to hold: under 200 square feet, under 30 inches above grade, not attached, at least 36 inches from any structure, and not serving a required exit door. A floating deck placed right next to the house still needs a permit even if it's small and low, because it fails the 36-inch distance test.

A code update that got stuck in court

Michigan's planned move to the 2021 MRC was scheduled for August 29, 2025, but a July 7, 2025 court order delayed that transition, leaving the 2015 MRC as the operative statewide standard. This is a genuine, documented disruption to a code update, distinct from states that simply haven't gotten around to updating.

A frost depth that varies sharply by region

Detroit, Grand Rapids, Lansing, and Ann Arbor enforce a 42 inch minimum footing depth, Traverse City and much of the Northern Lower Peninsula push to 48 inches, and most Upper Peninsula counties require 48 to 60 inches, a real structural cost difference across the state.

An extreme snow load range

Ground snow load runs roughly 20 to 30 pounds per square foot in Southeast Michigan, 30 to 40 in Mid-Michigan, up to 70 in Marquette and other Upper Peninsula locations, and can exceed 90 pounds per square foot in the Keweenaw Peninsula, known locally as Copper Country, a genuinely dramatic structural design range within one state.

Local enforcement handles most permits directly

Local building officials, not the state Bureau of Construction Codes itself, issue residential deck permits in the great majority of Michigan jurisdictions, with state inspectors stepping in only where no local department exists.

What people get wrong

The most common mistake is assuming a freestanding deck is exempt just because it isn't attached to the house. Michigan's 36-inch minimum distance requirement means a deck sitting close to the dwelling, even completely unattached, can still require a permit.

Building It Yourself? Here's What You'll Need

Popular tools and materials homeowners use for a deck construction project:

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Official Sources

Rules change and cities within a county may differ. This guide is general information, not legal advice — always confirm with your local building department. Reviewed by the StateDataIndex Editorial Team · Updated September 2026.