Do I Need a Permit to Build a Deck in Ann Arbor, MI?

Do you need a deck permit in Ann Arbor?

Ann Arbor enforces the Michigan Residential Code, the statewide code based on the 2015 International Residential Code (IRC) with Michigan amendments. Under it, you need a building permit for a deck that is any one of the following:

• Attached to the house
• Larger than 200 square feet
• More than 30 inches above grade
• Within 36 inches of any structure
• Serving a required exit door

That 36-inch rule is Michigan's own twist, and it catches people. In most states a small, low, freestanding deck is exempt. In Michigan a floating deck placed right next to the house still needs a permit, even if it is under 200 square feet and only a step off the ground, because it sits closer than 36 inches to a structure. For how Michigan compares statewide, see our deck permits in Michigan guide, and for the national rules, the complete deck permit guide.

The zoning compliance permit that catches small decks

Here is the part unique to Ann Arbor. Even when your deck is too small to need a building permit, the city still wants a zoning compliance permit. Ann Arbor lists a floating or detached deck of 200 square feet or less among the projects that skip the building permit but require a zoning compliance permit instead.

The zoning compliance permit is a planning review that confirms your deck fits the zoning rules for your lot: that it sits in an allowed location and meets the required setbacks. So the honest answer to "do I need a permit for a small deck in Ann Arbor" is that you almost always need at least one permit, either a building permit or a zoning compliance permit. The zoning compliance permit costs $25 for a project valued up to $10,000.

For a deck that does need a building permit, the zoning review happens as part of that application, so you do not file the zoning compliance permit separately.

Deck setbacks and where your deck can go

Unlike some cities, Ann Arbor has full zoning, and your deck has to respect it. A deck goes in the rear or side yard, never the front. No uncovered deck, porch, or platform can sit within 5 feet of the front lot line, and the city's expedited deck review is limited to rear and side yard locations.

The exact rear and side setbacks, what the city calls required open space, depend on your zoning district. Ann Arbor's single-family districts each set their own rear and side yard dimensions, so a deck that fits on one lot may violate the setback on the lot next door. Look up your parcel's zoning and setbacks at a2gov.org/zoning before you finalize the design, and the zoning compliance review will confirm the numbers. This setback check is a big part of why Ann Arbor asks for the zoning compliance permit even on small, exempt decks.

Frost footings: why Ann Arbor decks dig deep

Michigan winters drive one of the most important deck details here. Section R403.1.4 of the Michigan Residential Code requires exterior footings to extend 42 inches below grade, the local frost depth. A deck attached to the house transfers load to footings that must reach that 42-inch line so frost heave cannot lift the deck and pull on the house.

Michigan carves out one exception: a deck that is not supported by the dwelling, a true freestanding deck, does not have to carry its footings below the frost line. That is the same freestanding deck the 36-inch rule and the zoning compliance permit already govern, so the pieces connect. If your deck touches the house, plan on 42-inch footings and a footing inspection before you pour. When in doubt, size the footings for frost; a heaved deck is far more expensive to fix than to build right.

Historic districts and deck approvals

Ann Arbor has several local historic districts, including the Old West Side, one of Michigan's largest. If your home is in one, exterior work, a new deck included, needs a Certificate of Appropriateness from the city's Historic District Commission before you can pull the building permit. The city is explicit that exterior work in a historic district must be approved before the permit application moves forward.

The commission reviews how visible the deck is from the street and whether its design, railings, and materials fit the character of the district. A rear deck that is not visible from the street is usually straightforward, but budget extra time for the review, and do not order materials until you have the certificate in hand.

How to apply, what it costs, and how long it takes

Ann Arbor takes deck applications only through its online portal, STREAM. Paper applications and emailed PDFs are no longer accepted. For a deck you will generally upload:

• A site plan showing the deck location with dimensions to each property line
• A footing plan with footing widths and depths
• A framing plan showing beams, joists, ledger, spans, and cantilevers
• Decking material, elevation above grade, stair layout, and guardrail heights

Ann Arbor prices the building permit on the project's value. The permit fee is $100 for work valued up to $1,000, then $100 plus $10 per additional $1,000 of value, so most residential decks land between about $100 and $300. Add a plan review fee of 20 percent of the permit fee and $35 per inspection. A standalone zoning compliance permit for an exempt deck is $25.

Standard online review can run a few weeks during the busy season, but decks qualify for the city's expedited residential permit program, 15-minute Thursday appointments where a qualifying deck permit is issued on the spot. Decks up to 1,000 square feet and two levels, in the rear or side yard, are eligible. If a licensed contractor builds the deck, they must hold a Michigan residential builder license and be registered in STREAM; you can pull a homeowner permit only if the home is owner occupied.

Building a deck without a permit in Ann Arbor

Ann Arbor has a reputation for thorough enforcement, and skipping the permit is a poor bet. The city can issue a stop-work order, charge after-the-fact fees, and require you to uncover footings and framing so an inspector can verify what is hidden. A deck that violates a setback may have to be moved or removed.

The cost also follows you to closing. Unpermitted decks surface during home inspections and title work, and buyers routinely ask for permits to be resolved before they close. Permitting a finished deck after the fact costs more than doing it up front, and an unpermitted structure can give a homeowners insurer grounds to deny a claim if someone is hurt.