Journeyman Plumber (Commercial)
We place this role between $55,000 and $82,000 a year at mid experience, before overtime, bonus and on-call.
What the job actually is.
Installs and services commercial plumbing systems under a licence: domestic water, sanitary and vent, storm, gas, and the fixtures and equipment on the ends. Commercial work means larger pipe, more coordination and materials - cast iron, copper, carbon steel, press fittings - that behave differently.
What this role pays.
That band is mid experience, built from our own engagement history. Experience and region move it - the salary calculator applies both.
The federal occupation this role reports under is Plumbers, Pipefitters, and Steamfitters (SOC 47-2152), May 2025. Nationally it reports a median of $63,800 , with the middle of the market between $44,150 and $108,420. BLS counts this job inside that occupation rather than publishing it separately, so the figures cover a slightly wider group than this exact title.
Where it pays most.
Plumbers, Pipefitters, and Steamfitters across the metros we cover, May 2025. BLS publishes a median for 100 of them and withholds the rest, where the local sample was too small to be reliable.
| Metro | Median | Employed there |
|---|---|---|
| San Jose | $107,560 | 3,830 |
| Chicago | $103,380 | 12,750 |
| Minneapolis | $101,630 | 6,730 |
| Portland | $101,010 | 4,600 |
| Boston | $96,760 | 9,200 |
| Seattle | $95,230 | 6,350 |
| Detroit | $86,370 | 5,520 |
| Madison | $85,160 | 1,590 |
| McAllen | $46,110 | 360 |
| Myrtle Beach | $48,340 | 460 |
| Little Rock | $49,190 | 890 |
BLS Occupational Employment and Wage Statistics, May 2025. The last three rows are the lowest-paying metros in the same set. Headcount is metro-wide across every industry, not this trade alone.
Journeyman Plumber (Commercial) vs Master Plumber.
Both are licensed. The difference is which licence carries the permit: in most states it is the master's, which is why a shop can run a dozen journeymen behind one or two masters. The work itself is the same trade - rough-in, fixture setting, repair, and on commercial jobs the medical gas and backflow endorsements the building type demands. What changes at master level is legal responsibility and the paperwork attached to it, not the pipe.
Credentials that move an offer.
- State License
- Medical Gas
Licensing is a state question, not a national one. The Commercial Plumbing hiring page carries the state-by-state position, and every market page names the authority for that state.
What separates a strong candidate.
Everyone who applies for this seat will claim the experience. These are the things that distinguish the people who have it, and the questions that find out.
What to look for
- Pipe materials and joining methods described by application rather than preference
- Has worked to a riser diagram and coordinated sleeves and penetrations before the pour
- Medical gas or backflow certification where the work calls for it
Questions that find out
- How do you size a vent for a battery of fixtures, and what goes wrong if you undersize it? A strong answer Sizes from drainage fixture units and developed length against the table in whichever code is adopted here, and knows the common or circuit venting rules that apply to a battery. On the consequence, says trap seal loss from siphonage or back pressure rather than just slow drainage - because the real failure is sewer gas in an occupied room, and that is what the question is testing for.
- When would you use press fittings on a commercial domestic water line, and when would you not? A strong answer When the specification allows it, the application is inside the manufacturer listing for pressure and temperature, and the tool and jaws are right and in calibration. Not where the specification calls for soldered or brazed joints, where conditions prevent proper preparation, or outside the listing. Mentions deburring, insertion depth marks, and the unpressed joint - which is exactly why you still pressure test.
- Walk me through testing a sanitary system before the walls close. A strong answer Water or air test to the head and duration the adopted code requires, with the inspector there where that is required, sections isolated, every joint walked rather than watching a gauge from a distance, and nothing covered until it is signed off. Says who they notify and how far ahead.
- How do you size a storm drain, and what code are you working from? A strong answer Starts with the rainfall rate for this location rather than a number they remember, the roof area served including any wall that drains onto it, then the table for the slope they are running. Names the adopted code rather than the one they trained on, and raises overflow provision without being asked.
- Walk me through testing a DWV system, and tell me what a failed test usually turns out to be. A strong answer The test procedure, and then the honest part: most failures are not the pipe. A test plug or ball leaking, a cleanout or test tee left uncapped, a fixture arm nobody capped, or one joint that was not properly solvent welded. Someone who has done this says they check the plug before they condemn the system.
- Pressing versus soldering copper on a commercial job: how do you decide? A strong answer The specification decides, and the inspector. After that: whether hot work is permitted in an occupied space, crew skill, speed, and what the owner will be servicing in fifteen years. The important part of the answer is that a change from the specified method is a substitution request, not a field preference.
- How do you tie into an existing main in an occupied building? A strong answer Agrees a window and notifies the tenants, locates the valves and proves they actually hold rather than assuming - old valves often do not - and stages materials and a way back before cutting anything. Considers a line stop or hot tap where a shutdown is impossible. Finishes with flushing, disinfection and sampling before the water goes back to people.
- Describe a backflow installation and what the inspector is going to look at. A strong answer The right assembly for the degree of hazard, an approved and listed unit, correct orientation, height and clearance so it can actually be tested and rebuilt, a relief discharge that can take full flow to an air-gapped drain, protection from freezing, and a certified test at installation with the report filed. Knows the inspector looks hardest at the drain and the clearances.
- How do you rough in a bathroom group from the drawings, and what do you set first? A strong answer Checks the architectural dimensions and the fixture schedule against each other first, then sets the closet flange off the finished wall allowing for the finish thickness, because that is the one that cannot be moved later. Carriers and drainage next, water last. Coordinates any structural penetration before coring rather than after.
- What is your approach to supporting cast iron on a riser? A strong answer Carries the weight at each floor with riser clamps rather than letting the stack hang on its couplings, supports at the spacing the code and the manufacturer call for, braces against thrust at every change of direction on no-hub, and allows for movement. Can describe what a badly supported stack looks like when it finally lets go.
- How do you cut into a live sanitary line without flooding the floor below? A strong answer Stops the flow at source as far as possible - fixtures locked off, signs up, work scheduled for low use - then plugs upstream, sets containment and has a vacuum ready before the saw comes out. Accepts that in an occupied building something will arrive anyway and plans for it rather than being surprised by it.
- What do you check before you close a wall? A strong answer Test signed off and the inspection passed, every hanger and support in, insulation and firestopping complete, nail plates where pipe runs near the face, nothing left loose or unsupported, and photographs of what is about to disappear. Treats the photographs as the thing that saves an argument in two years.
- How do you handle a water hammer complaint on a finished building? A strong answer Finds the cause before buying parts: a fast-closing solenoid or flush valve, velocity too high because the line is undersized, piping that is not properly supported, or arrestors that have waterlogged. Fixes the cause, and only then adds arrestors where they belong. Someone who answers by fitting arrestors everywhere has treated the noise and not the problem.
- What is your process for sizing and installing a water heater and its venting? A strong answer Sizes on the actual demand and recovery profile rather than replacing like for like, checks the gas or electrical supply can carry it, matches vent category and material to the appliance, provides combustion air, handles condensate including neutralisation where needed, pipes the relief full size to a safe place with no valve in it, and addresses expansion on a closed system.
- How do you protect piping from freezing in an unconditioned space? A strong answer Routes it out of the cold first where there is any choice, then insulation at the right thickness, heat trace with a controller and some way of knowing it has failed, and drain-down provision. Knows the places that actually freeze - exterior walls, attics, loading docks, roof runs - and says plainly that insulation slows freezing rather than preventing it.
- What would make you stop and call your foreman? A strong answer Something specific: insulation that might be asbestos, an unidentified line, contaminated water, drawings that do not match the field, work beyond their licence, a safety issue, or being told to cover something that has not been tested. Says who they call and how quickly rather than just that they would raise it.
The mistake this seat invites
Hiring residential service plumbers for commercial construction. The diagnostic skill is real but the coordination and layout demands are a different job.
Where the role goes next
Journeymen progress to foreman, or to master plumber where the licence allows, and from there to estimating or ownership. Candidates ask this in the first conversation, and an employer who cannot answer it loses the people who had other options.
Interview kit for this role
- All interview questions for this role in the question bank.
- Printable interview scorecard built from these questions and signals.
- The Commercial Plumbing hiring kit - every role in the trade, with credentials and offer risks.
- Offer calculator starting from this role's pay band.
What the search actually takes.
We have closed 4 commercial plumbing searches in 2026 year to date, which is below the 8 we require before publishing a median. We would rather print the count than a number the sample cannot carry. The Hiring Index shows what we do and do not have.
What we have open in Commercial Plumbing right now.
3 live commercial plumbing searches on our board as of November 12, 2026. These are roles contractors have asked us to fill, not a sample set.
- Water/Wastewater Foreman - Pleasant Prairie, Wisconsin
- Senior HVAC/Plumbing Estimator - Bartlett, Tennessee
- Journeyman Plumber - Columbus, Ohio
Keep reading.
- 2026 Commercial Plumbing Salary Guide - the full benchmark by role.
- Commercial Plumbing recruiting - how we run this trade.
- Salary calculator - the band by experience and region.
- Commercial Plumbing hiring in Houston - one market in detail.
- Hiring Index - how long our searches actually take.
Other Commercial Plumbing roles we recruit
All 56 roles we recruit - every trade, every seat.
