HVAC Permits Ontario: What You Need, By City

The three permit layers every Ontario HVAC job needs

Ontario HVAC permits confuse homeowners because there is not one permit, there are three, and they come from three different regulators. Depending on the scope of work, your job may need one, two, or all three at the same time.

• TSSA fuels permit (gas). Any work on a natural gas or propane appliance, including a straight furnace or boiler replacement, falls under the Technical Standards and Safety Authority. The work has to be performed by a certified gas technician (G1, G2, or G3 Certificate of Qualification) employed by a business that holds an active TSSA Contractor Registration.[2]
• ESA electrical notification. The Electrical Safety Authority regulates any electrical work that goes with the HVAC install: a new disconnect for the outdoor condenser or heat pump, a new circuit for an electric air handler, or a panel upgrade to support a cold climate heat pump. The notification is filed by a Licensed Electrical Contractor (LEC) through the ESA portal, not the homeowner.[3]
• Municipal building permit. Almost every Ontario municipality requires a building (mechanical) permit for a furnace, boiler, ducted heat pump, or major ductwork change. The city permit sits on top of the TSSA and ESA layers and is the one that shows up on title, which is why it matters when you sell the house later.

Who files what: contractor vs homeowner responsibility

Almost all of this is the contractor's job. The homeowner's role is to verify that the paperwork actually happened, not to personally file any of it.

A homeowner can technically apply for the municipal building permit in their own name, and some cities allow a homeowner to file their own ESA notification on an owner-occupied single family dwelling. But the moment you put your name on the permit, you become the party of record for inspection, code compliance, and any enforcement action. The contractor walks away clean; you are the one who pays to tear out the drywall if the inspector fails it. Legitimate contractors never ask the homeowner to pull the permit.

TSSA gas permit: what's covered, how it's filed, typical timeline

The TSSA layer is the least visible to homeowners because it does not involve a counter visit or an inspector knocking on the door, but it is the one with the sharpest teeth. Natural gas is a compulsory trade in Ontario, which means working on gas equipment without the correct certification is illegal regardless of whether you pulled a city permit.[10]

A legitimate gas install flows like this:

1. Your contractor's business holds an active TSSA Contractor Registration (searchable by name through the TSSA public registry).
2. The actual technician on site holds a G1, G2, or G3 Certificate of Qualification appropriate to the BTU input and venting complexity of the appliance.
3. The work is documented by the contractor and, for new appliance installations or significant modifications, the contractor logs it in their records for potential TSSA audit. Ontario does not require a per-job pre-approval the way a city building permit works. The control is on the contractor side through registration and audit.
4. If something goes wrong later (carbon monoxide incident, fire, gas leak), TSSA traces the work back through the contractor's records and the technician's C of Q. An unregistered contractor has nothing to trace, which is why it is illegal and why insurance uses TSSA registration as a coverage hook.

There is no standard TSSA timeline in days because the contractor files internally rather than waiting for approval. The TSSA timeline is effectively zero for a registered contractor. The only time TSSA shows up on your property directly is during an incident investigation or when a homeowner specifically calls them in.

ESA electrical notification: when required, how to verify it

ESA comes into play any time the HVAC job touches electrical work. For a simple furnace replacement with an existing plug and existing breaker, you may not need ESA at all. For the jobs that do, here is when:[3]

• New air conditioner or heat pump outdoor unit: requires a new disconnect and usually a new circuit, which is an ESA notification.
• Panel upgrade (very common when a cold climate heat pump retrofit lands in a 100 amp panel that was already full): mandatory ESA notification and inspection.
• New electric air handler or electric backup coil: ESA notification for the new circuit.
• Mini-split with outdoor line set: ESA notification for the new outdoor disconnect.

To verify that the ESA filing actually happened, ask your electrician for the ESA Notification Number (also called an "authorization number") as soon as the work is filed. You can verify the licensed electrical contractor in the ESA public directory by company name. When the final inspection is complete, you should receive an ESA Certificate of Inspection. Keep it with your closing documents. Your insurance company may ask for it after a claim, and the next buyer's home inspector will ask for it during conditional period.

Municipal building permit: why it's usually required even for a same-capacity swap

Many Ontario municipalities adopt the $5,000 project value threshold as the point where a mechanical (HVAC) permit becomes required. A new furnace, heat pump, or central AC installed by a contractor almost always exceeds $5,000 once you include equipment, labour, and peripherals, which is why the "but it's just a swap" argument does not hold up. In addition, any of the following triggers a permit regardless of cost:

• Modification of gas piping or venting
• New or modified ductwork
• A new refrigerant line set between indoor and outdoor units
• Any change to the structural chase or mechanical room
• A new electrical circuit or panel upgrade

A bare like-for-like component swap with zero changes to any of the above is the only scenario where the city permit may legitimately be optional, and in practice that scenario almost never matches a real furnace or heat pump replacement. If a contractor is waving off the permit, they are betting that the city will not find out, not that the city does not care.

Toronto HVAC permit process

Toronto's residential permit fees are tied to a minimum fee plus a per-$1,000-of-construction-value calculation, and they are indexed roughly 4 percent per year. For 2026, the minimum residential permit fee sits at approximately $214.79, which is where a typical small HVAC swap lands if the declared project value is modest. Larger jobs scale upward at roughly $7 to $15 per $1,000 of declared construction value depending on the work category.[4]

Toronto made digital permit submission mandatory in January 2026, so the counter-visit workflow is gone. The major development backlog (about 25 months on average for large projects) does not apply to residential HVAC. Your contractor files through the Toronto Building digital portal, and simple mechanical permits move on the 10 to 15 business day timeline.

Mississauga and Brampton permit process

Mississauga publishes its cost and time frames directly on the city services portal, which makes it the most transparent of the GTA west municipalities. A residential alteration permit (which is the category a furnace or heat pump replacement falls into) averages about 7 weeks total, with the first review targeted at 10 business days. Resubmissions for incomplete applications add at least 2 weeks each, with no guaranteed timeline.[5]

Brampton targets a 10 business day first review and charges its trade permits on a per-trade basis, so a job that touches both mechanical and electrical pulls two separate trade permit fees.[6] One Brampton gotcha: if your property falls within a conservation authority zone (Credit Valley or TRCA), you may need a conservation authority approval before the city will accept the building permit application. That is uncommon for a furnace swap but it does come up for major additions that include HVAC.

Ottawa HVAC permit process

Ottawa is the cleanest story on timelines: the city runs its building permit service on a cost-recovery basis (the fees are set to fully offset the cost of permit processing and code enforcement), which is why the fees are tied directly to project type and scale rather than a flat schedule.[7] For simple residential HVAC work the city hits the 10 business day legislated target on complete applications, with summer peak season stretching total elapsed time to 5 to 14 weeks when other trades are also pulling permits.

Ottawa publishes its building permit pages in bilingual form, and the application portal accepts digital submissions for residential mechanical work. A furnace or heat pump replacement on a complete application should clear the first review window well inside a month.

Hamilton HVAC permit process

Hamilton is the most opaque of the five cities on published fee data. As of April 2026 the Hamilton permit office publishes fee schedules in the general building permit bylaw rather than a dedicated HVAC category, and the city does not publish a residential permit turnaround target the way Toronto, Ottawa, or Mississauga do.[8] What we know:

• Hamilton accepts email submissions for accessory dwelling units (ADUs) and new builds, which is a recent improvement over the old in-person counter.
• Trade permit fees land in the same $400 to $960 band as other large GTA-adjacent municipalities, but the exact number for a given job comes from the fee schedule in the general permit bylaw and the declared project value.
• For residential HVAC replacement, the practical default is to treat Hamilton as 10 business days for the first review on a complete application (the Ontario Building Code Act legislated target) and budget 4 to 6 weeks total including inspection scheduling.

If your contractor is quoting a Hamilton job, ask them to pull the fee directly from the current bylaw schedule during the quote rather than guessing, and ask them for the permit number as soon as it is issued so you can verify it on the city portal.

London HVAC permit process

London runs its building permit service through the city's Development and Compliance Services division, which handles plan review and inspections for residential mechanical work.[9] The city's permit categories follow the same $5,000 project value threshold pattern as the rest of Ontario, and London honours the 10 business day Ontario Building Code Act response window for complete applications on houses.

As of April 2026, London does not publish a dedicated HVAC permit fee tier on its public pages; the mechanical permit falls under the general residential building permit category, and the fee for a typical furnace or heat pump replacement lands in the same $200 to $500 band that the rest of Ontario averages. If you are working with a London contractor, ask them for the fee quoted by the city's permit counter for the declared project value rather than assuming it matches the GTA numbers, because London's flat-rate structure often runs slightly lower than the Toronto-area calculations.

What happens if you skip the permit

Homeowners skip permits for three common reasons: the contractor talked them into it, the contractor started the work before mentioning permits, or they wanted to save a few hundred dollars and figured nobody would notice. All three paths end the same way.

• Insurance claim denial. If your furnace causes a fire, or your AC short-circuits, or a poorly flared refrigerant line floods the basement, the insurance adjuster asks for the permit. No permit, no payout on the equipment-tied damage. Your homeowner policy generally does not cover unpermitted work, and the denial language is boilerplate across Canadian insurers.
• Sale of the home. Buyers and their home inspectors find unpermitted work during inspection. Some mortgage lenders require open permits to be closed before they fund. Unpermitted work either kills the deal or forces you to take the hit on price.
• City enforcement. If the city finds out from a neighbour complaint, an inspector doing a related project next door, or a permit search during your own later renovation, you get an order to comply. That means hiring a contractor to open up the work, pay the retroactive permit fee (often at double the normal rate), schedule the inspection, and sometimes pay an administrative penalty.
• Manufacturer warranty voided. Most major HVAC brands (Lennox, Carrier, Trane, Goodman, Napoleon) require installation by a properly certified technician to honour the parts and compressor warranty. Unpermitted gas work implies the installer was not registered, which triggers the exclusion in the warranty terms.
• TSSA gas service shutoff. TSSA has authority to shut down gas service until unpermitted gas work is inspected and brought into compliance. This is rare on residential retrofits but it happens, particularly after a related incident investigation.[2]

The permit fee is $200 to $900. The cost of getting caught without one is thousands to tens of thousands, plus a denied insurance claim if something later goes wrong. The math is not subtle.

How to verify your contractor actually pulled the permits

Trust but verify. Here is a 10 minute check that catches almost every permit shortcut before it becomes your problem.

1. Ask for the TSSA Contractor Registration number. It should be printed on their quote. Look it up in the TSSA public registry by company name. An active listing means they are legal to touch gas.
2. Ask for the ESA Licensed Electrical Contractor number if the job includes any electrical work. Look it up in the ESA LEC directory by company name.
3. Ask for the municipal building permit number as soon as it is issued. Every Ontario municipality with online permits lets you look up a permit by number or by property address. Takes 30 seconds.
4. Ask for the ESA Notification Number (also called the authorization number) if electrical work was filed. That is what you need to get the ESA Certificate of Inspection at the end.
5. Require copies of all inspection reports at job completion: the municipal mechanical final inspection sign-off, the ESA Certificate of Inspection if electrical was involved, and the contractor's own commissioning report for the appliance itself. Store them with your closing documents and warranty card.
6. Check the permit closes on the city portal a few weeks after the final inspection. An open permit that never closes becomes a title drag when you sell; a closed permit is a clean record.

If your contractor dodges any of these steps, treat it as a red flag and escalate. A legitimate Ontario HVAC company does all of this on every job as a matter of course. It is the cost of doing business and it protects both sides.

Related Guides

• How to Choose an HVAC Contractor in Ontario
• Ontario Building Code HVAC 2026
• HVAC Hidden Costs Ontario
• HVAC Consumer Protection Ontario
• HVAC Replacement Cost Ontario
• Electrical Panel Upgrade Cost Ontario
• Cold Climate Heat Pumps in Ontario

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