Ontario's new cooling rules: how to check your building's heat history

Ontario has moved to require landlords to keep rental units below a maximum temperature during hot weather — the cooling counterpart to the long-standing rule that units must be heated to at least 21°C in winter. If you rent, the practical question is the same one tenants ask every heat wave: will my landlord actually keep this place liveable, and what do I do if they don't?

The rules are only as good as enforcement. Before the next heat wave, it's worth knowing what your building's record actually looks like.

What the cooling rules generally cover

• A maximum indoor temperature. Where the rule applies, a unit can't be allowed to exceed a set temperature during defined summer months.
• Adequate cooling, not necessarily central air. A landlord may meet the standard through air conditioning, a cooled common space, or other measures — the obligation is the outcome, not a specific appliance.
• It interacts with local bylaws. Toronto has its own property-standards rules, and a failure to maintain adequate temperature can become a property-standards issue the City can act on.

Check the current City of Toronto and Province of Ontario guidance for the exact temperature thresholds and dates, since the details are what a complaint turns on.

Why your building's history matters

A landlord who has ignored heat or maintenance problems before is more likely to do it again. Two records tell you the most:

• Open orders and violations — if the City has already told this owner to fix heat, ventilation, or maintenance problems, that's a documented pattern, not a one-off.
• Bylaw investigations — complaints and enforcement activity show how often the building generates problems and how the owner responds.

For apartment buildings (3+ storeys or 10+ units), the RentSafeTO score adds a third signal: a building that scores low on maintenance is the kind most likely to leave a cooling request sitting.

What to do before the next heat wave

• Look up your building now, so you know what you're dealing with before it's 35°C.
• If you make a cooling request, put it in writing and keep a copy.
• If nothing happens, the City's property-standards process is the route — and a documented history of orders strengthens your case.

Check any address

Pull a building's outstanding orders & violations and its bylaw investigations, and — for apartments — its RentSafeTO report card. Start with the property snapshot for everything in one view, and turn on monitoring so a new order on your building lands in your inbox.