The Complete Guide to Becoming a Plumber

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What does a plumber actually do?

What a plumber does day-to-day

• Licensed plumber

  A plumber who has met state or local requirements (education, apprenticeship, and exams) and holds a valid license to perform plumbing work. Licensing protects consumers by ensuring the professional knows codes and safety practices.
• Journeyman plumber

  A plumber who has completed an apprenticeship (typically 4–5 years) and passed a journeyman exam. They can work independently under the general oversight of a master plumber. Requirements vary by state.
• Master plumber

  A plumber who has met additional experience and exam requirements beyond the journeyman level. A master can pull permits, run a business, and supervise journeymen and apprentices. Not all states use this tier.
• Tankless water heater

  A water heater that heats water on demand as it flows through the unit, rather than storing hot water in a tank. Tankless units are more energy-efficient and last longer (20+ years) but have higher upfront costs.
• Sump pump

  A pump installed in a basement or crawl space pit that automatically removes accumulated water to prevent flooding. Essential in areas with high water tables or heavy rainfall. Battery backup models protect against power-outage flooding.
• Septic system

  An on-site wastewater treatment system used in areas without municipal sewer. Wastewater flows into a buried tank where solids settle and bacteria break down waste; liquid drains into a leach field. Septic tanks should be pumped every 3–5 years by a licensed professional.
• Slab leak

  A water leak in the copper or PEX pipes that run beneath a home's concrete slab foundation. Slab leaks are caused by corrosion, shifting soil, or poor installation. Warning signs include hot spots on the floor, the sound of running water when all fixtures are off, unexplained increases in the water bill, and cracks in the foundation. Detection typically involves acoustic listening equipment or infrared cameras. Repair methods include spot repair (jackhammering through the slab to fix the pipe), rerouting the line through the ceiling or walls, or epoxy pipe lining. Costs range from $500 for a simple spot repair to $3,000–$5,000 for rerouting.
• Water hammer arrestor

  A small plumbing device installed near valves and appliances to absorb the shockwave that occurs when water flow is suddenly stopped — the loud banging noise known as water hammer. Arrestors contain a sealed air chamber and a piston that compresses when the pressure spike hits, cushioning the impact. They're installed on washing machine supply lines, dishwasher connections, and near quick-closing solenoid valves. A water hammer arrestor costs $10–$30 for the part and $100–$200 installed by a plumber. Without one, water hammer can loosen pipe joints, damage valves, and eventually cause leaks.
• PEX piping

  Cross-linked polyethylene (PEX) tubing used for residential water supply lines. PEX has largely replaced copper in new construction and repiping because it's flexible (bends around corners without elbow fittings), resists corrosion and scale buildup, handles freeze-thaw cycles better than rigid pipe (it can expand without bursting), and costs 25–40% less than copper for materials and labor. PEX comes in three types: PEX-A (most flexible, best for tight bends), PEX-B (most common, good balance of cost and performance), and PEX-C (least flexible, lowest cost). It's connected using crimp rings, clamp rings, or expansion fittings. Repiping a typical home from copper to PEX costs $4,000–$8,000 versus $8,000–$15,000 for copper-to-copper.
• Polybutylene pipe

  A gray plastic water supply pipe (stamped 'PB2110') widely installed in U.S. homes from 1978 to 1995 as an inexpensive alternative to copper. Polybutylene was eventually found to deteriorate from the inside out when exposed to chlorine and other oxidants in public water supplies — micro-fractures develop in the pipe walls over 10–25 years, leading to sudden, catastrophic leaks with no visible warning. An estimated 6–10 million homes in the U.S. were plumbed with polybutylene. Most plumbing professionals recommend full re-piping with PEX or copper ($4,000–$15,000 for a typical home) rather than spot repairs, because failure is progressive and unpredictable. Many insurance companies will not insure homes with polybutylene supply lines, and its presence can affect resale value. Polybutylene is easy to identify: gray (sometimes white or black) flexible tubing, typically 1/2" to 1" diameter, with copper or plastic crimp rings at connections.

Career transitions into Plumber

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