Landlord Heating Requirements in Ontario: Minimum Temperature Rules by City
There's no provincial heating law. Every city sets its own rules. If you don't know your municipality's bylaw, you're guessing. Here's exactly what each major city requires.
There Is No Provincial Heating Law
This trips up almost every landlord. You'd think Ontario has one clear rule: "Keep it at 21°C." It doesn't. The province has no single heating temperature law that applies everywhere.
Instead, heating requirements come from municipal bylaws. Your city council decides the minimum temperature, the heating season dates, and the fines. Toronto's rules are different from Ottawa's. Hamilton's are different from Windsor's.
What does this mean for you? You can't just Google "Ontario heating law" and call it a day. You need to look up yourcity's property standards bylaw. If you own properties in two different cities, you might have two different sets of rules.
The Bottom Line
No province-wide heating law exists.Your obligations come from your municipality's property standards bylaw. Most cities require 21°C. Some require 20°C. The heating season dates vary too. Look yours up.
Heating Rules by City
Here are the heating requirements for Ontario's major municipalities. If your city isn't listed, contact your local bylaw office or search your city's name plus "property standards bylaw heating."
| City | Min Temp | Heating Season | Bylaw Reference |
|---|---|---|---|
| Toronto | 21°C (70°F) | Sept 15 – June 1 | Municipal Code Ch. 497 |
| Ottawa | 20°C (68°F) | Oct 1 – May 15 | Bylaw 2013-416 |
| Hamilton | 21°C (70°F) | Sept 15 – June 1 | Property Standards Bylaw |
| Mississauga | 21°C (70°F) | Sept 15 – June 1 | Property Standards Bylaw |
| Brampton | 21°C (70°F) | Sept 15 – June 1 | Property Standards Bylaw |
| London | 21°C (70°F) | Sept 15 – June 1 | Check local bylaw office |
| Kitchener | 21°C (70°F) | Sept 15 – June 1 | Property Standards Bylaw |
| Windsor | 21°C (70°F) | Oct 1 – May 15 | Check local bylaw office |
Don't Assume October 1
A common mistake is assuming the heating season starts October 1 everywhere. In Toronto, it starts September 15. That's two full weeks earlier. If you wait until October, you're already in violation.
Who Is Responsible for Heat?
This depends on who controls the heating system and what your lease says.
Landlord Controls the System
If you run a central boiler, a shared furnace, or any heating system that the tenant cannot independently control, you are 100% responsible for maintaining the minimum temperature. This is the case in most apartment buildings.
Tenant Has Their Own Furnace
If the tenant has their own furnace (common in rented houses) and the lease explicitly states the tenant pays for gas and controls the heating, then the tenant manages their own heat. But the furnace itself still has to work. If it breaks, you fix it.
The Lease Is Silent
If your lease doesn't say anything about who provides heat, you're on the hook. Silence defaults to the landlord. Don't assume the tenant knows they're responsible unless it's written down.
Even when the tenant pays for gas, you're still responsible for maintaining the equipment. A broken furnace is a maintenance issue under the RTA. The tenant can file a T6 if you don't fix it.
When Can You Turn Off the Heat?
Only after the heating season ends. Period.
In Toronto, that's June 1. In Ottawa and some other cities, it's May 15. Until that date arrives, the heating system must be operational and capable of maintaining the minimum temperature.
Here's where landlords get into trouble: it's April 20, it's 25°C outside, and they shut the boiler down to save on gas. Then a cold snap hits three days later and the building drops to 16°C overnight. Now you've got a bylaw violation and angry tenants calling 311.
The bylaw doesn't care about the weather forecast. It cares about the calendar. If it's still heating season, the heat stays available. You don't have to run it at full blast on a warm day, but the system has to be ready to fire up the moment temperatures drop.
Don't Gamble on the Weather
A warm week in March doesn't mean heating season is over. If you shut down the system and a cold snap follows, you're in violation. Keep the system available until the official end date.
What Happens If You Don't Comply
You can get hit from two directions at once. That's the part most landlords don't realize.
Municipal Bylaw Enforcement
When a tenant calls 311, a bylaw officer shows up with a thermometer. If your building is below the minimum temperature, you get a work order. You'll have a deadline to fix it. If you don't comply with the work order, fines follow.
In Toronto, fines can reach up to $100,000 for corporations and $50,000 for individuals. Other cities have their own fine schedules, but none of them are cheap.
LTB: The T6 Application
On top of the municipal fine, your tenant can file a T6 maintenance application at the Landlord and Tenant Board. If the Board finds you failed to maintain the rental unit (and inadequate heat counts), they can order a rent abatement. That's money back to the tenant for every day they froze.
So yes, it's possible to get fined by the city and ordered to pay rent abatement by the LTB. Double jeopardy? Not technically, but it sure feels like it.
Enforcement Is Municipal, Not Provincial
Heating complaints go to your local bylaw office, not the LTB. This means faster enforcement and quicker fines. The LTB only gets involved if the tenant separately files a T6 application.
Heating vs Cooling: The Full Picture
Ontario now has temperature rules for both winter and summer. Here's how they compare:
| Heating (Winter) | Cooling (Summer) | |
|---|---|---|
| Source | Municipal bylaws | Bill 64 (provincial) |
| Temperature | 21°C minimum (most cities) | 26°C maximum |
| Where | All habitable rooms | Common areas only |
| Season | Varies (Sept 15 or Oct 1) | May 15 \u2013 Sept 15 |
| Enforcement | Municipal bylaw | Municipal bylaw |
For the full breakdown on summer cooling obligations, read our Bill 64 Cooling Requirements guide.
Common Mistakes
Using the Wrong Heating Season Dates
Toronto starts September 15. Not October 1. If you own properties in multiple cities, track each one separately. Getting the date wrong by two weeks is still a violation.
Turning Off Heat on a Warm Day
It's 22°C outside in late March, so you kill the boiler. Then it drops to 2°C overnight. Your building is now freezing and you're in breach. The system stays on until the season ends.
Assuming the Tenant Is Responsible
Unless your lease explicitly says the tenant controls and pays for their own heating, you're responsible. A verbal agreement doesn't count. It has to be in the lease.
Skipping Furnace Maintenance
Your furnace dies on January 15 because you haven't serviced it since 2019. Now you're scrambling for an emergency HVAC tech at premium rates while your tenant files a T6. Annual maintenance is cheaper than a repair bill plus rent abatement.
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