Replacing your own water heater in Michigan: what the law lets you do

What the Michigan homeowner exemption says

The plumbing license law is MCL 339.6107. It says only a licensed master or journey plumber may do plumbing, and it lists exemptions. One is a homeowner installing their own plumbing, building sewer or private sewer in a single-family dwelling, with a permit. Without the permit, the exemption does not apply.

LARA’s permit page says the same thing from the other side. Work does not start until the enforcing agency issues the permit, and the applicant has to be a licensed plumbing contractor or a homeowner installing their own plumbing. The only repairs exempt from a permit are the working parts of a faucet or valve and clearing stoppages. A water heater is neither, which means a swap needs a permit even when you do it yourself.

Two local building departments say it directly. Sterling Heights tells residents they need a plumbing permit to install a water heater, and Delta Township lists a water heater change out among the projects that always require one. No state page names water heaters outright, so the state rule is the general one above, and your city has the last word.

The extra step for a gas water heater

An electric heater is mostly a plumbing job with a circuit attached. A gas heater adds a gas connection, a flue and a shutoff, and Michigan treats those as mechanical work.

LARA’s mechanical FAQ says replacing a gas water heater requires a Michigan mechanical license (in the HVAC equipment or gas piping and venting classification) and a Michigan plumbing contractor’s license, with both a mechanical permit and a plumbing permit. We read that answer partly through a search summary of the PDF, so confirm it with LARA before you plan around it. If it holds, any page saying that any plumber can swap a gas heater leaves out half the rule.

For homeowners, the mechanical side has its own exemption. LARA’s mechanical permit page says an owner of a single-family dwelling who occupies it may do the work without a license, and the FAQ says that homeowner may pull a permit and install a heating system if they affirm ownership and occupancy and get the inspection. Delta Township adds a limit: a homeowner may pull trade permits only if they are doing the work themselves, and that comes from a township FAQ, not state law.

That is what the law allows, which is a different question from what we would advise, and on gas we would stop. DTE’s safety page says to contact a licensed professional if the pilot flame of an appliance goes out, and that the professional should relight it. If an appliance pilot needs a professional, a new gas connection does too. Read the gas line page before you touch a gas fitting, and keep the pilot light guide nearby.

If you smell gas at any point

Leave the house. From a safe place call 911, then DTE’s gas leak hotline at (800) 947-5000 or Consumers Energy at 800-477-5050. Both lines are open around the clock. DTE says not to use electrical equipment, phones, switches or open flame inside and not to go back in until first responders or DTE say it is safe. (800) 477-4747 is DTE’s electric line, not gas.

What the inspector looks at

Your inspector’s checklist is local, and Michigan’s amendments to the model code were not part of our review. ICC’s summary of the 2021 International Plumbing Code, which Michigan adopts, describes the relief valve discharge pipe in detail and shows what the code expects.

The discharge pipe must not connect directly to the drainage system. It ends in an air gap in the same room as the heater, it is not smaller than the valve outlet and runs full size to the air gap, and it ends no more than 6 inches above the floor, a waste receptor or a floor drain. It has no threaded end, no valves and no tees, and it serves a single relief device. A capped or threaded end is the kind of detail a do-it-yourself job tends to get wrong.

The permit also puts a second person in front of connections you cannot easily judge yourself, which counts for a lot on a gas appliance.

Setting the temperature

Whoever installs the heater, set the thermostat deliberately. The Consumer Product Safety Commission advises 120 degrees Fahrenheit. The Department of Energy says lowering a heater from 140 to 120 can reduce the risk of scalding, and that people with weakened immune systems or chronic lung conditions may prefer to keep 140. Its building guideline says serious burns can result from 140 degree water in as little as five seconds. Choose the setting on purpose, and tell everyone in the house what it is.

What the permit costs in four Michigan cities

Fees are local and change each fiscal year, so check your own office. These four are published, and we read each one.

Grand Rapids lists $52 for the application and $21 for a water heater, effective July 1, 2026. Sterling Heights lists $55 for the application and $40 for a water heater, the same for a tankless one, on its 2026-2027 chart. Flint’s adopted schedule has a $95 base fee and $15 for a water heater, with a minimum of $160 per inspection. Dearborn charges a $100 administrative fee plus an $80 minimum permit fee, so $180 at minimum including one rough and one final inspection, and $15 for a hot water tank.

Grand Rapids also lists an administrative fee of $173 for work done before the permit, a good reason to apply first.

If someone else installs it without a license

Hiring an unlicensed installer can leave you with a heater that nobody inspected. Under MCL 339.5601, practicing a regulated occupation without a license is a misdemeanor, with a fine up to $500 or up to 90 days in jail, or both. A second offence carries up to $1,000 or one year, and a third or later offence is a felony. Those penalties fall on the person doing the work.

LARA’s Bureau of Construction Codes handles complaints about working without a permit or a license. It does not rule on contract, money or warranty disputes. Check any installer on the LARA lookup before work starts.

A sensible way to decide

If your heater is electric and your city allows homeowner permits, the law leaves room to do it yourself with an inspection. If it is gas, the licenses and permits multiply and so does the downside. Either way, call the building department before you buy a unit, read do you need a permit to replace a water heater in Michigan, and look at the water heater replacement page for cost evidence if you decide to hire.