Plumber Job Description

A plumber builds and repairs the piping that brings potable water into a building, carries waste and storm water out of it, and, in many jurisdictions, delivers fuel gas to furnaces, ranges and water heaters. The trade splits into two kinds of work. New construction follows the building schedule from underground pipe to final trim. Service and repair starts with a symptom, a wet ceiling or a backed-up floor drain, and ends when the plumber finds the cause and fixes it. Both answer to a plumbing code adopted by the state or city and enforced by an inspector who signs off before walls close and again before occupancy.

New construction: underground, rough-in, trim

On a new building the first plumbing goes in before the slab is poured. The crew lays out building drains and the sewer lateral at the grade the code calls for, sets cleanouts, and holds the underground on a water or air test until the inspector passes it. Once framing is up, rough-in begins: drain, waste and vent stacks, horizontal branches, hot and cold supply in copper, PEX or CPVC, plus the hangers, firestopping and nail plates that protect the system once drywall goes on. Trim is the visible finish: setting water closets and lavatories, hanging wall-mounted fixtures on carriers, connecting the water heater, installing thermostatic mixing valves, flushing lines and starting the system.

Commercial jobs add scale and coordination. On a hospital wing or a mid-rise apartment building, plumbing routes are modeled alongside ductwork, sprinkler mains and cable tray, and a plumber who can read a coordination drawing and a riser diagram saves the foreman rework.

Service and repair

Service plumbers run a different day. One call is a slab leak, the next a sewer backup, a dead water heater, or low pressure that turns out to be a corroded galvanized line. The kit is a sewer camera and locator, a sectional drain machine or jetter, test gauges and a moisture meter. Diagnosis comes first; then the plumber prices the repair, explains it to the owner in plain words, and leaves the work area cleaner than it was found.

Gas, backflow and specialty systems

Gas piping in black iron or corrugated stainless steel tubing is sized from code tables, pressure tested and leak checked before any appliance is lit. Backflow prevention assemblies keep irrigation systems, boilers and commercial kitchens from contaminating the public supply. In hospitals, piping for oxygen, medical air and vacuum is a discipline of its own, with separate installer certification and its own inspection regime.

Codes on the job

The model codes behind local plumbing rules include the Uniform Plumbing Code, published by IAPMO, and the International Plumbing Code, published by the International Code Council. A state or city adopts one, often with local amendments, and the edition in force decides details such as trap arm length, vent sizing and the drainage fixture units a pipe may carry. Knowing which edition the inspector is enforcing is part of the job.

Entry routes

Plumbing is learned on the job, under a licensed plumber, with classroom time layered on top. The usual route is a registered apprenticeship. The United Association, the union for the pipe trades, runs Registered Apprenticeship Programs that blend paid, on-the-job training with classroom learning, and plumbing is one of its career tracks alongside pipefitting, steamfitting, sprinkler fitting, HVACR and welding. Outside the union, merit-shop contractors and trade associations sponsor their own registered programs, and some new entrants start with a community college certificate and then work as a helper while they log hours.

A high school diploma or equivalent is the typical starting point. Algebra, the geometry behind offsets and grade, and comfort with a tape, a level and a set of drawings matter more on the first day than any prior job title. A clean driving record helps for service roles, where the truck is the shop.

Licensing: Texas as a worked example

Licensing is set by state boards or, in some places, by cities and counties, and the rules differ from one jurisdiction to the next. Texas shows how a tiered system works. The Texas State Board of Plumbing Examiners lets a registered Plumber's Apprentice sit for the Journeyman Plumber exam after at least 8,000 hours of experience in the plumbing trade, along with either a 48-hour training course approved by the board or enrollment in or completion of a training program approved by the U.S. Department of Labor Office of Apprenticeship. To take the Master Plumber exam, a Texas journeyman must have held that license for at least two years, or for at least one year after completing a Department of Labor approved apprenticeship program. Anyone working in another state should read that state board's current rules before counting hours.

Certifications worth adding

• Medical Gas Systems Installer certification to the ASSE 6010 standard, issued by independent certifying bodies, for oxygen, medical air and vacuum piping in healthcare buildings.
• Backflow Prevention Assembly Tester (ASSE 5110), from ASSE International, where the water purveyor requires a certified tester.
• OSHA 10-Hour or 30-Hour Construction card, issued through the Occupational Safety and Health Administration's Outreach Training Program.

Skills that separate good plumbers

Reading isometrics and riser diagrams. Sizing drainage by fixture units and supply by demand. Soldering, brazing, press and expansion connections done right the first time. Running a camera and locator and reading what the screen shows. Explaining a repair price to a homeowner without jargon. The physical side counts too: crawlspaces, attics, trenches and mechanical rooms are the office, and the work involves lifting, kneeling and long days.

As a rough guide, reaching journeyman takes four to five years of supervised work, and a master license adds one to several more years depending on the state.

Pay

The Bureau of Labor Statistics' May 2025 Occupational Employment and Wage Statistics put the median annual wage for plumbers, pipefitters and steamfitters at $63,800. The 10th percentile was $44,150 and the 90th percentile $108,420, across 465,840 jobs. BLS does not report plumbers separately from pipefitters and steamfitters, so those figures cover industrial fitters as well as residential and service plumbers.

The industry breakdown shows where the jobs sit. Plumbing, heating, and air-conditioning contractors employed 330,570 workers in the occupation in May 2025, at a median of $63,010. Hospitals employed 2,600, at a median of $76,530. A plumber weighing a move from contracting into facilities work can use those two rows as a starting point, then check local union scales and employer pay schedules.

Projections

For this occupation group, the BLS Occupational Outlook Handbook expects employment to rise 7 percent between 2025 and 2035, a pace it calls much faster than the average for all occupations, and it projects about 42,000 openings in each year of that decade, on average.

Lead service lines

For water piping, the regulation to watch is EPA's Lead and Copper Rule Improvements, issued in October 2024, which require drinking water systems across the country to identify and replace lead pipes within 10 years. The final rule, published in the Federal Register on October 30, 2024, requires water systems to comply starting three years after promulgation, with November 1, 2027 listed as a compliance date. In Texas, for example, the Texas Commission on Environmental Quality, on a page updated in October 2026, still states that public water systems must comply with the rule starting November 1, 2027. Service line replacement is pipe work: excavation or trenchless pulls, a new copper or plastic service, and reconnection at the meter and at the building wall. Plumbers who know local excavation rules, tapping procedures and customer-side permitting have a direct line into that work, whether they bid utility contracts or replace the private side for property owners.

Federal water heater rules

Federal efficiency standards shape what goes on the truck. A Department of Energy final rule published Dec. 26, 2024 would have set amended energy conservation standards for gas-fired instantaneous (tankless) water heaters. Under the Congressional Review Act, that rule was disapproved, and DOE withdrew it as of May 20, 2025. Installers should still confirm the current federal and state efficiency rules for any unit they size and set, since standards are revised on their own cycles.

Advancement

The ladder runs from apprentice to journeyman to master. From there, plumbers move into foreman and superintendent roles on commercial jobs, estimating and project management, service management at a residential shop, plumbing inspection for a city or county, or their own contracting business with a master license, a bond and insurance. Specialty certifications in medical gas and backflow testing open hospital and testing work to a licensed plumber who wants a narrower lane.

Dear Hiring Manager,

I am applying for the Journeyman Plumber position at Ridgeline Mechanical. I finished my four-year apprenticeship this spring and passed my journeyman exam on the first attempt. For the past two years I have run rough-in and trim on multifamily buildings for Cedar Point Plumbing, and I want to bring that experience to your commercial and healthcare work.

On my most recent project, a 96-unit apartment building, I led a three-person crew through underground, rough-in and trim on two floors. We passed every rough inspection without a correction notice, and I worked with the sprinkler and HVAC foremen to reroute a waste stack that clashed with a duct main before anyone cut a hole. I keep my own layout notes and update the as-built drawings every Friday so the office never has to guess where a cleanout went.

I also spent a year on Cedar Point's service side. That taught me to run a sewer camera, find a slab leak with a moisture meter and a pressure test, and explain a repair price to a homeowner clearly enough that they trusted the number. I hold an OSHA 10-Hour card and I am working toward ASSE 6010 medical gas installer certification, because I know your shop takes on hospital work and I want to be useful there from day one.

I am comfortable with copper, PEX, CPVC, cast iron and PVC, press and expansion fittings, and gas piping in black iron and CSST. I show up early, I keep a clean gang box, and I ask questions before I make expensive mistakes.

I would welcome the chance to talk about how I can help your crews. Thank you for your time.

Sincerely, Marcus Delgado