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Going out on your own

How to start a steamfitting business in Ontario

Steamfitter/pipefitter (307A) is a compulsory trade focused on industrial and commercial process and pressure piping — work that layers TSSA pressure-piping registration and ASME/CWB welding qualifications on top of the certificate.

Steamfitting at a glance

Licence to do the work
Required — 307A C of Q (compulsory)
Path in
Apprenticeship — 8,280 hours (about 4–5 years)
Regulated by
Skilled Trades Ontario + TSSA (pressure piping)
Insurance baseline
$5M CGL on industrial sites
Union route
UA locals — the dominant route

Steamfitting is a compulsory trade in Ontario. You cannot legally do this work, or hire people to, without the required certification. This is the key difference from non-compulsory trades and the first thing to sort out.

The steps to start your steamfitting business

  1. 1

    Incorporate your company

    Most contractors incorporate (Ontario or federal) to limit personal liability, look credible to larger clients, and access tax advantages once profitable. You choose a named or numbered company, set directors and share structure, and file the articles. Budget roughly $400–$600.

    Full guide: Incorporation
  2. 2

    Register your CRA accounts

    Get a Business Number, then register for HST/GST (mandatory once you exceed $30,000 in revenue, and worth registering sooner to claim input tax credits), a payroll account if you will hire, and corporate income tax. This is free and done through the CRA.

    Full guide: CRA Registration
  3. 3

    Register for WSIB

    Construction is a mandatory WSIB sector. Independent operators and partners in construction generally must register even with no employees, and clients and general contractors will require a valid WSIB clearance certificate before letting you on site.

    Full guide: WSIB & Provincial
  4. 4

    Get certified and licensed for steamfitting

    307A Steamfitter/Pipefitter is a compulsory trade. Pressure piping is regulated by TSSA and typically requires registered welding procedures and ASME Section IX / CWB-qualified welders. To contract industrial mechanical work you incorporate, carry the trade tickets, and register with owner safety systems.

    Full guide: Trade Licensing
  5. 5

    Get insured

    Carry Commercial General Liability (typically $2M, $5M for commercial/industrial work), plus tools and equipment, commercial auto, and — depending on scope — builders risk and professional liability. Many contracts and clients specify minimum coverage before you can quote.

    Full guide: Insurance
  6. 6

    Set up health, safety & compliance

    Meet your Occupational Health and Safety Act duties: a health and safety policy, required training (WHMIS, Working at Heights where applicable), and — for commercial and public work — often COR® certification. This is also where any trade-specific safety tickets live.

    Full guide: Safety Compliance
  7. 7

    Stand up your operations

    Open business banking, set up construction-specific accounting, and understand your trust obligations under the Construction Act (holdback, prompt payment, and adjudication). This is the back office that keeps you paid and out of trouble.

    Full guide: Operational Setup
  8. 8

    Get bid-ready and win work

    Assemble your prequalification package — incorporation and WSIB documents, insurance and bonding letters, safety program, key personnel, and project references — then quote, send proposals, and collect on invoices. This is where a construction business actually makes money.

    Full guide: Bid Readiness

Insurance for a steamfitting business

Industrial pressure work carries high consequence-of-failure exposure. Expect $5M CGL requirements on industrial sites plus possible pollution liability.

Your launch checklist

The whole page in one list. Screenshot it, stick it on the dash of the truck.

  • Incorporate your company
  • Register your CRA accounts
  • Register for WSIB
  • Get certified and licensed for steamfitting
  • Get insured
  • Set up health, safety & compliance
  • Stand up your operations
  • Get bid-ready and win work

Steamfitting questions, answered

Do you need a licence? How much does it cost? See the FAQs.

Steamfitting overview

Licensing, regulators, and certifications at a glance.

Skip the paperwork. Let AEC Stack set it up

AEC Stack runs the whole process for a steamfitting business: incorporation, CRA, WSIB, trade licensing, insurance, compliance, and the operations to win your first contract.

Start your steamfitting business