Going out on your own
How to start a commercial roofing business in Ontario
Flat/low-slope commercial roofing is a different business from residential shingles: membrane systems (TPO, EPDM, mod-bit), manufacturer-certified warranties, property-manager clients, and service contracts that recur — with a much higher barrier and ceiling than steep-slope.
Flat & Commercial Roofing at a glance
- Licence to do the work
- Not required — Working at Heights + torch safety mandatory; manufacturer certs gate the work
- Path in
- Flat-roof crews — torch/heat-weld skills, then manufacturer certification
- Regulated by
- MOL (heights, hot work); manufacturers (warranty programs)
- Insurance baseline
- High CGL — fire from torch work is the defining exposure
- Union route
- Roofers locals on ICI work
The steps to start your commercial roofing business
- 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
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
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
Handle flat & commercial roofing licensing & permits
No provincial trade licence (449A is voluntary); Working at Heights is mandatory. The real gates are manufacturer certification (Carlisle, Soprema, Firestone, Sika Sarnafil approve the contractors whose installs they warranty), torch-safety certification for mod-bit work, and the insurance/bonding to satisfy commercial owners.
Full guide: Trade Licensing - 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
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
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
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 commercial roofing business
Torch work makes fire the headline exposure — insurers scrutinize hot-work procedures, and one membrane fire can end a company. High CGL limits, strict hot-work permits, and fire-watch discipline are non-negotiable.
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
- Handle flat & commercial roofing licensing & permits
- Get insured
- Set up health, safety & compliance
- Stand up your operations
- Get bid-ready and win work
Flat & Commercial Roofing questions, answered
Do you need a licence? How much does it cost? See the FAQs.
Flat & Commercial Roofing 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 commercial roofing business: incorporation, CRA, WSIB, permits, insurance, compliance, and the operations to win your first contract.
Start your flat & commercial roofing business