Michigan examines its journey plumbers on the 2021 Michigan Plumbing Code — the state’s own code, built on the 2021 International Plumbing Code with Michigan amendments — in an open-book written examination of 125 questions in 180 minutes, passed at 75 percent, administered through PSI for a $100 fee. And the written paper is only part of the route: Michigan also requires a separate practical examination, administered by the Department, built around a copper project. The PassProfessor Michigan Journey Plumber program prepares candidates for the written examination, and states plainly what written preparation cannot do for the practical.
This program is part of the expanding PassProfessor catalog — join the notify list and we’ll email you when enrollment opens.
What this credential certifies
The Michigan Journey Plumber credential is the license of the qualified working plumber in Michigan: the person who has shown, by examination, command of the plumbing code Michigan actually enforces and of the state acts that frame construction and the skilled trades, and who has also shown, by a hands-on practical, that the knowledge is in the hands as well as in the head. That second element sets Michigan apart in this catalog. Many states examine on paper alone. Michigan examines twice — once in writing, through PSI, and once in copper, through the Department.
The written examination is built on three named references: the 2021 Michigan Plumbing Code, Public Act 230, and Public Act 407. The first of those names deserves emphasis, because Michigan candidates are surrounded by material that gets it subtly wrong. The examination is not based on the bare International Plumbing Code. It is based on the Michigan Plumbing Code — the 2021 IPC as Michigan amended it — and where Michigan’s amendments change a provision, the Michigan text is the credited text. A candidate who prepares from an unamended national book is preparing from a close relative of the right code, and close relatives lose marks.
For the full treatment — the reference set worked through in detail, the open-book method, the practical described plainly, and a study plan — read the companion guide at /michigan-journeyman-plumber-exam-guide/.
The examination at a glance
| Item | Verified position |
|---|---|
| Program | Michigan Journey Plumber |
| Tested code | 2021 Michigan Plumbing Code — the 2021 International Plumbing Code with Michigan amendments; the bulletin names the Michigan code, never the bare IPC |
| Adopted code | The same: tested and adopted are the 2021 Michigan Plumbing Code |
| Other named references | Public Act 230 and Public Act 407 |
| Book status | OPEN book |
| Questions | 125 |
| Time allowed | 180 minutes |
| Passing score | 75 percent |
| Examination fee | $100 |
| Written examination vendor | PSI |
| Practical examination | A separate practical, administered by the Department, built around a copper project — required in addition to the written examination; see the disclosure below |
| Administrator note | PassProfessor is independent and is not affiliated with the State of Michigan, its Department, or PSI |
The Michigan code: why the amendments are the examination
A model code becomes a state code through amendment, and Michigan’s amendments are not footnotes. They are the places where Michigan looked at the national text and chose differently — on materials, on methods, on the conditions Michigan work actually presents. Examination writers know exactly where those choices live, because an amendment is a decision, and decisions are examinable in a way that unchanged national text often is not. The Michigan delta, for this program, is therefore not a supplement added to a national core; it is the centre of the written paper.
Preparation follows from that. The working book is the 2021 Michigan Plumbing Code itself, amendments in place — not an IPC with a Michigan errata sheet tucked inside. Candidates should be able to say, for the provisions they are examined on, whether Michigan kept the national text or changed it, and if it changed, what Michigan requires instead. The two Acts named in the bulletin complete the state layer: Public Act 230 and Public Act 407 are examinable references alongside the code.
Open book: what it rewards, and what it does not forgive
Michigan’s written paper is open book, and candidates routinely misread what that promises. Open book does not mean the answers are in the room; it means the finding of answers is part of the skill being examined. The arithmetic sets the real terms: 125 questions in 180 minutes is well under a minute and a half per question. At that pace, a candidate who must search the code from a standing start on every item runs out of paper before running out of knowledge. The candidates who pass are those who know the Michigan code’s structure cold — which part governs a described system, where its tables sit, how its amendments are flagged — and use the book to confirm and to settle fine detail, not to learn the subject at examination speed.
So open-book preparation is navigation training as much as knowledge training: a tabbed, familiar, personally annotated working copy of the Michigan Plumbing Code; repeated timed drills in which the book is used the way it will be used in the room; and honest accounting of which questions are answered from knowledge, which from fast lookup, and which from slow lookup — because the third kind is a timing failure waiting to be scheduled. This program is built around that accounting.
The practical: a plain disclosure
Michigan’s route includes a separate practical examination, administered by the Department, built around a copper project. This page discloses that plainly because it decides what this program is and is not.
A written preparation program — this one included — prepares candidates for the PSI written examination. It cannot rehearse a copper project. It cannot put flux, fitting and torch in a candidate’s hands, judge the quality of a joint, or certify that a candidate’s workmanship will satisfy a Department examiner. No arrangement of written questions substitutes for building the project with real materials.
What candidates must therefore do, outside this program, is practise the practical as a practical: work copper with their own hands, repeatedly, to a standard they would be content to have judged, and take the Department’s own published arrangements for that examination as the authority on its format and scheduling. The written and practical halves of the Michigan route reward different kinds of readiness, and a complete candidate prepares for both — in the right medium for each.
What the written examination covers
The PSI bulletin names the reference set — the 2021 Michigan Plumbing Code, Public Act 230, and Public Act 407 — and the code defines the territory the questions walk.
Drainage, waste and vent systems. Sizing and grading drainage piping, venting that protects trap seals, cleanout access, and the building drain and sewer connection — read through Michigan’s amended text wherever Michigan has amended it.
Water supply and distribution. Demand, sizing, pressure, backflow protection and cross-connection control, and the protection of potable water, in the form the Michigan code states them.
Traps, fixtures and interceptors. Trap construction and limits, fixture requirements, and interceptor duties — the everyday provisions a journey plumber is expected to apply without hesitation and locate instantly when a detail must be checked.
Materials, methods and sizing calculations. Permitted materials and joints as Michigan amends them, and the worked sizing problems the code’s tables support — answered, at this paper’s pace, by candidates who know which table governs before they open to it.
The state acts. Public Act 230 and Public Act 407, the Michigan statutes the bulletin names: the legal frame around the code and the credential, examined in their own right rather than as background reading.
The route, in order
The route runs in two strands that meet at the credential. On the written strand: obtain the 2021 Michigan Plumbing Code and the two named Acts — schedule the written examination through PSI and pay the $100 examination fee — sit 125 questions in 180 minutes, open book — and reach the passing score of 75 percent. On the practical strand: prepare hands-on, with real copper and real tools, and take the Department-administered practical built around the copper project, under the Department’s own arrangements. Neither strand substitutes for the other; the written result does not excuse the practical, and bench skill does not answer written questions about Michigan’s amendments.
What makes this examination demanding
The written paper’s demand is speed inside a specific book. One hundred and twenty-five questions against 180 minutes, in a code that is the national model as Michigan changed it, defeats two kinds of candidate: the one who knows plumbing but not the Michigan amendments, and the one who knows the amendments but must hunt for every answer. The 75 percent standard leaves limited room for either weakness. The practical adds a demand of a different kind entirely — judged workmanship, on the day, in copper — which no amount of written fluency can offset. Michigan’s route, taken whole, is demanding precisely because it refuses to let either half of a plumber’s competence stand in for the other.
What the PassProfessor program will cover
The written examination, prepared as a Michigan paper. Original practice material written to the 2021 Michigan Plumbing Code — Michigan amendments in place throughout, never the bare IPC — together with the Public Act 230 and Public Act 407 layer the bulletin names. Every item is written from scratch against primary sources; no item is drawn from another provider’s material.
Open-book craft, taught as craft. Timed practice at the real shape of the sitting — 125 questions, 180 minutes, book in hand — with the emphasis open-book success actually requires: code structure memorised, amendment locations known, lookup reserved for confirmation and fine detail.
The practical, disclosed and bounded. This program prepares candidates for the written examination only. The Department-administered copper practical is a hands-on examination that written preparation cannot rehearse, and the program says so wherever the route is described, so no candidate mistakes a written program for complete preparation for the Michigan credential.
Independence, stated plainly. PassProfessor is an independent preparation provider, not affiliated with the State of Michigan, its Department, or PSI, and this program is not a Michigan course. Completing it confers no license and no exemption; the state alone licenses, candidates register for the written examination through PSI, and the practical is taken under the Department’s arrangements.
Tell me when enrollment opens. The Michigan Journey Plumber program is in the works and enrollment is not yet open. Leave an email address and PassProfessor will write to you when the program is ready — and only about this program. No date is promised, because the program will open when it meets the standard described above, not before.
Frequently asked questions
Which code is the Michigan Journey Plumber written examination based on?
The 2021 Michigan Plumbing Code — the 2021 International Plumbing Code with Michigan amendments. The bulletin names the Michigan code, and preparation should use it, not the bare IPC.
Is the written examination open book?
Yes. The written paper is open book — which, at 125 questions in 180 minutes, rewards candidates who know the Michigan code’s structure and use the book for confirmation and detail rather than for searching.
How many questions are on the written examination, and how long is it?
125 questions, with 180 minutes allowed.
What score passes the written examination?
75 percent.
What does the written examination cost?
The examination fee is $100, paid for the PSI sitting. That is the testing fee, separate from any preparation program.
Who administers the written examination?
PSI administers the written examination. Its bulletin names the reference set: the 2021 Michigan Plumbing Code, Public Act 230, and Public Act 407.
Is there a practical examination as well?
Yes — and this matters. Michigan requires a separate practical examination, administered by the Department, built around a copper project. It is distinct from the PSI written examination.
Can this program prepare me for the copper practical?
No. Written preparation cannot rehearse a hands-on copper project. This program prepares candidates for the written examination; the practical must be prepared for hands-on, with real materials, under the Department’s own arrangements for that examination.
Does Michigan test on a different edition from the one it has adopted?
No. For Michigan, tested and adopted are the same: the 2021 Michigan Plumbing Code governs the work and the written examination alike. The Michigan task is not edition-switching; it is knowing the Michigan amendments inside the current code.
Is PassProfessor affiliated with the State of Michigan or PSI?
No. PassProfessor is an independent preparation provider. The state alone licenses plumbers; PSI administers the written examination and the Department administers the practical.
When does enrollment open?
The program is in the works and enrollment is not yet open. Leave an email address on this page and PassProfessor will write to you when the program is ready — and only about this program.