Section 20(1) is the whole foundation: “A landlord is responsible for providing and maintaining a residential complex, including the rental units in it, in a good state of repair and fit for habitation and for complying with health, safety, housing and maintenance standards.” Section 20(2) adds that this applies even if you knew about the problem before you signed, and s.4 makes any lease term to the contrary void.
In Toronto, the minimum indoor temperature is 21°C from 1 October to 15 May — not the 15 September to 1 June range you will see on most websites, which has been wrong since April 2025.
Toronto does not require landlords to install air conditioning. Where a cooling system already exists it must be operated to keep the unit at or below 26°C from 1 June to 30 September. Since 1 July 2026 you also have a statutory right to install your own window or portable unit.
What is a landlord responsible for maintaining in Ontario?
Everything in the complex and everything they supplied. Section 20(1) has two distinct limbs, and a tenant can win on either one: the unit must be in a “good state of repair,” and it must be “fit for habitation.”
The Board’s Interpretation Guideline 5 treats adequate heat, light and ventilation, serviceable plumbing, and secure windows and doors as core, and gives infestations of rodents or vermin, bathrooms with backed-up sewage and rooms with broken windows as examples of a unit that is not fit for habitation.
Section 20(2) closes the obvious loophole: the duty “applies even if the tenant was aware of a state of non-repair or a contravention of a standard before entering into the tenancy agreement.” Renting a place knowing the windows are bad does not waive anything, and s.4 voids any lease clause that tries to.
Minimum temperature: the three layers, and why the numbers differ
There are three separate rules here and they are constantly merged into one wrong sentence. They do different jobs and they carry different numbers and dates.
| Rule | Temperature | Dates | Where it applies |
|---|---|---|---|
| Provincial maintenance standard — O. Reg. 517/06, s.15(1) | At least 20°C | No dates — year-round | Only municipalities without their own property standards by-law. Not Toronto. |
| Provincial vital service — O. Reg. 516/06, s.4 | At least 20°C | 1 September to 15 June | All of Ontario, for the purpose of s.21 (withholding a vital service) |
| City of Toronto — Ch. 497 / By-law 1511-2025 | At least 21°C | 1 October to 15 May | Toronto, including Etobicoke, where the unit is normally heated at the landlord’s expense |
Both provincial figures are measured the same way: 1.5 metres above floor level and one metre from exterior walls, in habitable space and areas intended for normal tenant use, excluding locker rooms and garages. Toronto’s current wording adopts the same 1.5-metre measurement point.
Two qualifications on the Toronto rule that are easy to miss. It applies only to a unit “normally heated at the landlord’s expense” — if you pay your own heat, the duty is on you to run it. And where the unit is already at 21°C, the landlord “is not required to operate a heating unit.”
Outside 1 September to 15 June, a heat failure is not a vital-services breach under s.21 — it is an ordinary repair issue under s.20(1). Both are actionable; they just go on different forms.
Does my landlord have to provide air conditioning in Toronto?
No. This is the point most reporting on the 2026 by-law gets wrong.
Toronto’s By-law 1511-2025 repealed the old Chapter 497 “Heating” and replaced it with “Indoor Temperature Standards,” in force 1 June 2026. Its cooling provision requires that any installed cooling system be “operated from June 1 to September 30 so as to maintain an indoor temperature of not more than 26 degrees Celsius” — and it adds, for greater clarity, that this “applies only to properties that have existing air conditioning systems.”
The City says it plainly: property owners are not required to install air conditioning or cooling equipment where it does not already exist.
That 26°C duty is also not new. It already sat in the Property Standards by-law at Chapter 629, s.629-38.F, amended in December 2024 and in force from 30 April 2025. What is genuinely new on 1 June 2026 is the amenity-space obligation: an owner or operator of an apartment building with at least one existing amenity space must keep at least one such space at or below 26°C from 1 June to 30 September, where cooling is not provided in all dwelling units. “Apartment building” here means a purpose-built rental building with three or more storeys and ten or more rental units.
Can I install my own air conditioner?
Since 1 July 2026, yes, as a matter of provincial law. Section 36.1 of the Act, added by the Helping Homebuyers, Protecting Tenants Act, 2023, provides that “a tenant may install and use a window or portable air conditioner in a rental unit for which the landlord does not supply air conditioning,” subject to conditions.
The conditions in s.36.1(3) are practical ones: notify the landlord in writing before installing; do not damage the unit or the complex; install it safely and securely; and comply with any applicable municipal property standards by-law or other applicable law. A landlord may prohibit installation in prescribed circumstances under s.36.1(2) — I have not been able to read that prescribing regulation, so check it before relying on an absolute right.
On cost: where the landlord is obliged to supply electricity, s.36.1(5) lets them increase the rent — but s.36.1(7) caps the increase at the actual cost of the electricity for running the unit, or a reasonable estimate where actual cost cannot be established. And under s.36.1(8) and (9), if you remove the unit or stop using it seasonally, the landlord must decrease the rent by the same amount. It is a cost pass-through, not a rent increase in disguise.
Pests: whose problem is it?
The landlord’s. The Act contains no pest-specific provision — the words “pest,” “vermin” and “infestation” do not appear in the operative text — so it runs through the general s.20(1) duty. The Board’s Maintenance and Repairs brochure says it directly: “A landlord must also take steps to control pests such as cockroaches and mice.”
In municipalities without their own by-law, O. Reg. 517/06 s.46 requires the complex to be “kept reasonably free of rodents, vermin and insects,” extermination to comply with applicable law, and openings and holes to be “screened or sealed to prevent the entry of rodents, vermin, insects and other pests.” In Toronto the equivalent duty sits in the Property Standards by-law rather than the provincial regulation, because s.224(1)(a) disapplies the provincial standards where a municipal by-law exists.
Guideline 5 treats an infestation as going to the “fit for habitation” limb of s.20(1) — which matters, because that is a lower bar to clear than proving a specific standard was breached.
Mould
Here is the honest position, and it is not what most articles imply. Ontario has no mould-specific statute, no LTB standard, no prescribed spore count and no “safe level.” The words “mould” and “mold” do not appear anywhere in the Act.
Mould is dealt with under the general s.20(1) duty — good state of repair, and fitness for habitation. The only prescribed mention anywhere is a surface-cladding standard in O. Reg. 517/06 s.39(1), requiring interior cladding of walls and ceilings to be “maintained free from holes, leaks, deteriorating materials, mould, mildew and other fungi” — and that regulation does not apply in Toronto. Toronto has no mould-specific standard either; it is enforced through the general wall-and-ceiling and ventilation provisions.
Practically, that means a mould case is won on the underlying cause — the leak, the failed ventilation, the damp-proofing — and on habitability evidence, not by citing a threshold. Anyone quoting you an Ontario mould limit is inventing it.
Appliances the landlord supplied
If it came with the unit, the landlord maintains it and, if necessary, replaces it.
O. Reg. 517/06 s.40: “Appliances supplied by the landlord of the rental unit shall be maintained in a good state of repair and in a safely operable condition,” and “appliances” expressly includes refrigerators, stoves, clothes washers, clothes dryers, dishwashers and hot water tanks. Toronto’s by-law requires every supplied appliance to be “maintained in good repair and good working order.”
The Board’s brochure gives the clearest statement of the principle: “All things that the landlord provides to the tenant must be kept in working order… If something no longer works due to normal wear and tear or because it breaks or wears out, the landlord must repair it so that it works properly, or replace it.”
Vital services: heat, water, fuel, electricity, gas
Section 21(1) prohibits a landlord from withholding “the reasonable supply of any vital service, care service or food that it is the landlord’s obligation to supply under the tenancy agreement,” or deliberately interfering with it, at any time during the tenancy and before an eviction order is executed.
“Vital service” is defined in s.2(1) as hot or cold water, fuel, electricity, gas, or — during the prescribed part of the year — heat. The prescribed period for heat is 1 September to 15 June.
Two details worth having. Section 21(2) deems the landlord to have withheld the service where they were obliged to pay a supplier, failed to pay, and the supplier cut it off as a result — so “the gas company shut it off” is not a defence if the landlord did not pay the bill. And the Board’s brochure adds the point tenants most need to hear: this rule “applies even if the tenant’s rent is overdue.” A landlord cannot cut services to force payment.
What can I actually do about it?
Three routes, and they stack.
1. Tell the landlord in writing first. This is not a formality. Section 30(2) requires the Board, in determining the remedy, to “consider whether the tenant or former tenant advised the landlord of the alleged breaches before applying to the Board.” A paper trail is worth money at a hearing.
2. File a T6 (maintenance) or a T2 (vital services). A T6 runs on s.29(1) para 1, a breach of s.20(1). A T2 covers vital services, substantial interference, harassment, illegal lock changes and illegal entry. Both carry the same hard deadline in s.29(2): no application more than one year after the conduct occurred.
What the Board can order on a maintenance application, from s.30(1):
| Remedy | s.30(1) |
|---|---|
| Abatement of rent | para 2 |
| Authorise a repair and order the landlord to pay its cost to you | para 3 |
| Order the landlord to do specified work within a specified time | para 4 |
| Order payment for your damaged or destroyed property and other out-of-pocket expenses | para 5 |
| Prohibit the landlord from charging a new tenant more than the last lawful rent, until the work is done | para 6 |
| Prohibit the landlord from giving notice of a rent increase, or from taking one already noticed, until the work is done | paras 7 and 8 |
| Terminate the tenancy | para 1 |
Guideline 5 also confirms the Board can award general damages for the breach in addition to an abatement.
3. Call the City. In Toronto, Municipal Licensing and Standards enforces the property standards by-law. For purpose-built rental buildings of three or more storeys and ten or more units, that runs through RentSafeTO, the City’s apartment building standards programme, which requires owners to register and renew annually and audits building maintenance. Toronto’s by-law penalties are not trivial: conviction fines up to $100,000, a special fine equal to the fair market value of the economic advantage obtained from the contravention, and continuing offences at up to $10,000 per day, with the daily total permitted to exceed $100,000.
Buying an older Etobicoke building, or holding one?
Send me the address and I will tell you what the maintenance obligations actually cost on that vintage of building — boilers, windows, ventilation, the RentSafeTO exposure if it is ten units or more — and what it means for value. If you are a tenant with a problem, tell me and I will point you at the right form. No pitch, no obligation.
connect@jatindua.com · 437-987-1925 · Book a free consultation
Confidential. Reviewed personally and answered within 24 hours. I never share, sell or distribute your information.
Frequently asked questions
What temperature does a landlord have to keep an apartment in Toronto?
At least 21 degrees Celsius from 1 October to 15 May, under the City of Toronto’s Indoor Temperature Standards by-law, and only where the unit is normally heated at the landlord’s expense. The often-quoted range of 15 September to 1 June is out of date; it was changed by By-law 1395-2024, in force 30 April 2025. The separate provincial maintenance standard is 20 degrees with no date range, but it does not apply in Toronto because Toronto has its own property standards by-law.
Does my landlord have to provide air conditioning in Toronto?
No. Toronto does not require landlords to install air conditioning where none exists. Where a cooling system already exists it must be operated from 1 June to 30 September so as to keep the indoor temperature at or below 26 degrees Celsius. Since 1 June 2026 an apartment building with an existing amenity space must also keep at least one such space at or below 26 degrees where cooling is not provided in all units.
Can a tenant install a window air conditioner in Ontario?
Yes. Since 1 July 2026, section 36.1 of the Residential Tenancies Act allows a tenant to install and use a window or portable air conditioner in a unit where the landlord does not supply air conditioning. The tenant must notify the landlord in writing beforehand, must not damage the unit, must install it safely, and must comply with applicable by-laws. Where the landlord supplies the electricity, they may charge the actual cost of running it and must remove that charge if the unit is removed or not used.
Is a landlord responsible for pest control in Ontario?
Yes, under the general repair obligation in section 20(1). The Act has no pest-specific provision, but the Landlord and Tenant Board’s guidance states that a landlord must take steps to control pests such as cockroaches and mice, and an infestation goes to whether the unit is fit for habitation.
Is there a mould standard in Ontario?
No. There is no mould-specific statute, no LTB standard, no prescribed spore count and no safe level in Ontario law. Mould is dealt with under the general section 20(1) duty to keep the unit in a good state of repair and fit for habitation. The only prescribed mention is a surface-cladding standard in O. Reg. 517/06 section 39(1), which does not apply in Toronto.
Does my landlord have to fix the fridge or stove?
Yes, if the landlord supplied it. O. Reg. 517/06 section 40 requires appliances supplied by the landlord to be maintained in a good state of repair and in a safely operable condition, and expressly includes refrigerators, stoves, washers, dryers, dishwashers and hot water tanks. The Board’s guidance is that if something breaks or wears out the landlord must repair or replace it.
What counts as a vital service in Ontario?
Hot or cold water, fuel, electricity, gas, and heat during the prescribed part of the year, which is 1 September to 15 June. Section 21 prohibits a landlord from withholding or deliberately interfering with the reasonable supply of a vital service they are obliged to supply, and this applies even if the tenant’s rent is overdue.
What can the LTB order if my landlord will not do repairs?
Under section 30(1) the Board can order an abatement of rent, authorise a repair and order the landlord to pay its cost, order specified work within a specified time, order payment for your damaged property and out-of-pocket expenses, prohibit the landlord from raising the rent or charging a new tenant more until the work is done, or terminate the tenancy. A maintenance order cannot include an administrative fine. You must apply within one year of the conduct, and section 30(2) requires the Board to consider whether you told the landlord first.
Sources
- Residential Tenancies Act, 2006, S.O. 2006, c. 17 (e-Laws). Sections 2(1), 4, 20, 21, 29, 30, 31, 36.1, 224 and 225. Consolidation current from 1 July 2026; accessed 10 August 2026.
- O. Reg. 517/06 — Maintenance Standards (e-Laws). Section 15 (20°C, no dates), section 39 (cladding and mould), section 40 (appliances), section 46 (pests). Applies only where there is no municipal property standards by-law.
- O. Reg. 516/06 (e-Laws). Section 4, prescribing 1 September to 15 June as the part of the year during which heat is a vital service, at 20°C.
- City of Toronto By-law 1511-2025 — Indoor Temperature Standards. Enacted 17 December 2025, in force 1 June 2026. The 21°C / 1 October to 15 May heating rule, the 26°C cooling rule for existing systems, and the new amenity-space obligation.
- City of Toronto — Indoor temperatures in apartment units. Confirms the 1 October to 15 May range and that owners are not required to install cooling. Page updated 30 July 2026.
- City of Toronto — RentSafeTO: Apartment Building Standards. Scope of the programme and the three-storey, ten-unit threshold. Page updated 31 July 2026.
- LTB Interpretation Guideline 5 — Breach of Maintenance Obligations. The two limbs of s.20(1), habitability examples, and general damages.
- LTB brochure — Maintenance and Repairs. Pests, supplied items, and the vital-services rule applying even where rent is overdue.
Related reading
- The T6 maintenance application, explained
- The T2 application: enforcing tenant rights at the LTB
- Above-guideline rent increases: when they are legal and how to fight one
- The Etobicoke bungalow inspection checklist for 1950s and 1960s homes
- The Ontario LTB forms guide — which form does what
About the author — Jatin Dua, Etobicoke real estate agent
I am Jatin Dua, a Realtor with RE/MAX Quantum Realty, working out of 799 The Queensway in Etobicoke. A lot of Etobicoke’s rental stock is mid-century, which means heating systems, ventilation and windows are live issues rather than theoretical ones. I wrote this page mostly because the Toronto heating dates changed and almost nothing online has caught up.
Reach me at connect@jatindua.com or 437-987-1925.