How to Hire a Contractor in Ontario: WSIB, Insurance, Contracts and Red Flags

Most renovation disasters are not about bad workmanship. They are about hiring the wrong person in the first place: someone with no insurance, no WSIB, a vague contract and a big deposit. The good news is that vetting a contractor in Ontario takes about an hour and a handful of documents. Here is the checklist we use before any contractor joins our network, and that you can use yourself.

1. WSIB clearance certificate

The Workplace Safety and Insurance Board covers workers who are injured on the job. In Ontario, construction businesses with employees must be registered, and many sole proprietors in construction must be as well.

Why it matters to you: if a worker is hurt on your property and the contractor is not registered, you can be exposed to a claim. Ask for a WSIB clearance certificate. It is free for the contractor to generate online and shows they are registered and in good standing. You can also verify it yourself on the WSIB website with the business name. If a contractor says they are “exempt,” ask them to explain why, and be cautious.

2. Liability insurance

Ask for a certificate of insurance showing commercial general liability of at least $2 million, with the policy dates current. Call the broker on the certificate to confirm it is real and active. Liability insurance covers damage to your house (a fire from a plumbing torch, a collapsed ceiling, a flooded basement) caused by the contractor’s work. Without it, you are relying on your own homeowner policy, which may not cover contractor-caused damage.

For roofing and tree work, insurance and WSIB matter even more because the injury rates are the highest in the trades.

3. Trade licences

Some trades are compulsory in Ontario, meaning the person doing the work must hold a Certificate of Qualification or be a registered apprentice working under one:

• Electricians. Work must be done by a Licensed Electrical Contractor registered with the Electrical Safety Authority (ESA), with an ESA permit and inspection. Ask for the ECRA/ESA licence number; it should appear on their truck and paperwork.
• Plumbers. Must hold a 306A Certificate of Qualification through Skilled Trades Ontario.
• Gas work. Anyone touching a gas line, furnace or gas water heater needs a TSSA gas technician licence.
• HVAC refrigeration. Refrigeration and air conditioning mechanics (313A) is also compulsory.

General contractors, roofers, painters, tile setters and carpenters are not licensed trades in Ontario. There is no provincial licence to check, which is why WSIB, insurance, references and a solid contract do the work instead.

4. The Ontario Consumer Protection Act

Ontario’s Consumer Protection Act, 2002 (with a replacement Act passed in 2023 that is being phased in) gives homeowners several protections worth knowing. Details change, so confirm current rules with the Ministry of Public and Business Service Delivery, but the main points have been:

• The 10 percent estimate rule. If a contractor gives you an estimate, the final bill cannot exceed it by more than 10 percent unless you agreed to the change in advance. This is why change orders should be in writing.
• The 10-day cooling-off period for door-to-door (direct) agreements. If a contract over $50 was signed at your home after an unsolicited visit, you have 10 days to cancel for any reason, in writing, with a full refund.
• The ban on door-to-door sales of certain HVAC and water equipment. Since 2018, furnaces, air conditioners, water heaters, water treatment systems, air cleaners and duct cleaning cannot be sold door to door at all unless you invited the company for that purpose. A knock on the door to sell you a furnace is itself a violation.
• Written contracts over $50. You are entitled to a written agreement that spells out the goods and services, the total price and the payment terms.
• No charging for unsolicited work. If a contractor does work you did not agree to, you do not have to pay for it.

5. Deposits and payment schedule

Ontario does not set a hard legal cap on renovation deposits, so this is about good practice:

• A 10 to 15 percent deposit to hold a start date and cover ordering is normal. For projects with long-lead custom items like cabinets or windows, a larger material deposit can make sense, but it should be tied to a specific order with a receipt.
• Never pay more than a third up front, and never pay cash with no receipt.
• Pay by milestone, not by calendar: demolition complete, rough-in inspections passed, drywall, substantial completion, final after your walkthrough and permit close-out.
• Hold back the last 10 percent until deficiencies are fixed and the permit is closed. For larger projects, the Ontario Construction Act’s holdback rules may apply.

6. What a written contract should include

• Legal business name, address, HST number and the owner’s name
• Detailed scope of work, room by room, including what is not included
• Materials and products specified by brand and model, or clear allowances with a process for pricing changes
• Fixed price or a clearly defined cost-plus arrangement
• Payment schedule tied to milestones
• Start date and estimated completion date, with how delays are handled
• Who pulls permits (it should be the contractor) and who pays for them
• Change order process: everything in writing, priced, signed by both parties before the work happens
• Clean-up, disposal and site protection
• Warranty on workmanship (one to two years is common) and how to make a claim
• Confirmation of WSIB and liability insurance

If the contractor’s standard contract is a one-page quote with a signature line, write an addendum covering the gaps.

7. What Tarion and HCRA do and do not cover

New homes in Ontario are built by builders licensed by the Home Construction Regulatory Authority (HCRA) and covered by a Tarion warranty. Neither applies to renovations, additions, roofs or any work on your existing home. Your only protections on a renovation are the contract, the Consumer Protection Act and the contractor’s own warranty. That is why the paperwork above matters.

8. Red flags

• Shows up unsolicited at your door, especially after a storm
• Wants a large cash deposit, or offers a discount for cash with no receipt
• Will not provide WSIB clearance or an insurance certificate, or the certificate is expired
• Cannot give you addresses of recent local jobs you can drive past
• Pushes you to sign today because “the price goes up tomorrow”
• Offers to “cover your deductible” on an insurance claim
• Asks you to pull the permit in your name (this shifts the liability onto you)
• Has no fixed business address, only a cell phone
• Quote is a single line with a price and no scope
• Online reviews are all from the same month, or the company name changes every couple of years

9. References and reputation

Ask for three references from the past two years and actually call them. Ask about budget, schedule, communication and how problems were handled. Check the Ontario corporate registry to see how long the business has existed. Search the business name with “complaint” and “court.” Look for jobs in your neighbourhood and knock on a door.

10. Get more than one quote, but compare scope not just price

Three quotes that are wildly different almost always have different scopes. Line them up side by side and ask each contractor about the differences. The lowest quote is often the one that left something out.

The short version

WSIB clearance, insurance certificate, trade licences where required, a detailed written contract, a small deposit with milestone payments, and no one who knocked on your door. That covers most of the risk.

We check WSIB, insurance, licensing and references before a contractor joins the LocalHomePro network, so when you request quotes you are starting from a vetted list rather than a search engine. Tell us about your project and get free, no-obligation quotes from local Windsor-Essex pros. Get free quotes.