Trade Playbook

Plumbing

Compulsory trade, certification required

Plumbing is a compulsory trade in Ontario. You need a 306A Plumber Certificate of Qualification to do the work, and many municipalities additionally require a Master Plumber licence to pull plumbing permits.

Plumbing at a glance

Licence to do the work
Required — 306A C of Q (compulsory); municipal Master Plumber licence to pull permits
Path in
Apprenticeship — about 9,000 hours (5 years)
Regulated by
Skilled Trades Ontario + your municipality (+ TSSA for gas)
Insurance baseline
$2M CGL — confirm water-escape coverage
Union route
UA locals

The licensing layer, explained

Plumbing work requires a 306A Plumber Certificate of Qualification (a compulsory trade), or apprentice status under a certified plumber. To pull plumbing permits, many municipalities (e.g., Toronto) require a municipal Master Plumber/Plumbing Contractor licence. Backflow prevention work needs separate certification, and any gas-appliance connections require a TSSA gas fitter ticket.

Certifications in this trade

Insurance to expect

Water is the most common source of property-damage claims in construction. Carry at least $2M CGL, and confirm coverage for water escape and "resultant damage" — a small leak can cause six-figure damage in a finished building.

Keep reading

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