What's the difference between a plumber and pipefitter?

Both plumbers and pipefitters work with pipe systems, but they serve very different industries and purposes.

Plumbers focus on systems that move water, waste, and gas in residential and commercial buildings. This includes supply lines, drain systems, fixtures like toilets and sinks, water heaters, and sewer connections. Plumbers are licensed under provincial regulations and work primarily in buildings people live and work in.

Pipefitters (also called steamfitters) specialize in industrial and mechanical piping systems — think high-pressure steam lines, HVAC systems, oil and gas refineries, and manufacturing facilities. Their work involves much higher pressures and temperatures than typical residential plumbing, and they follow different codes and safety standards suited to industrial environments.

In Ontario, these are separate trades with separate licensing. A licensed plumber holds a 306A trade certificate, while pipefitters hold a 307A. The apprenticeship paths, exams, and governing standards are distinct. You wouldn't hire a pipefitter to replace your water heater, and you wouldn't hire a plumber to work on an industrial boiler system.

For anything in your home — drains, water heaters, pipes, fixtures — you want a licensed plumber with a 306A certificate. In Ottawa, all plumbing work in residential settings must be done by or under the supervision of a licensed plumber to comply with the Ontario Building Code.

If you have a home plumbing project in mind, Ottawa Pro Plumbing's licensed 306A plumbers are happy to help — feel free to reach out for a free consultation.