When should I winterize outdoor plumbing in Ontario?

In Ontario, outdoor plumbing should be winterized before the first hard frost — temperatures at or below 0°C sustained for several hours. In the GTA and southern Ontario, this typically occurs in October, though early November is a common target. In northern Ontario, September or October is more appropriate. Complete outdoor faucet shutoff and irrigation system blowout before the first hard frost event, not after.

How do I shut off outdoor faucets for winter in Ontario?

For a frost-free sillcock (the most common type in Ontario): confirm no hose is left connected — a connected hose prevents the self-draining feature from working. For a standard hose bib with an interior shut-off: close the interior shut-off valve, then open the outdoor tap to drain the remaining water in the pipe between the valve and the outdoor faucet, and leave the outdoor tap in the open position over winter to allow any residual water to drain and to indicate if any water remains.

How do I winterize an irrigation system in Ontario?

Irrigation systems must be blown out with compressed air to remove all water from the underground lines and heads before freezing temperatures arrive. This is typically done by a licensed irrigation contractor with appropriate compressor equipment. Attempting to blow out an irrigation system with an undersized compressor can damage irrigation heads. Most Ontario irrigation contractors schedule fall blowouts in September and October — book early as their schedules fill quickly.

Should I flush my water heater in fall before winter in Ontario?

Fall is a reasonable time to flush sediment from a tank-type water heater if it hasn't been done in the past 12 months. Before the heater is called on for heavy duty through a full Ontario winter, confirm the anode rod is in good condition, the T&P relief valve is functional, and the setpoint is at 60°C minimum for Legionella prevention. Annual service in fall prepares the heater for the highest-demand season.

What should I check on the heating system plumbing in fall?

For hydronic (hot water) heating systems: check the system pressure gauge (normal is typically 12–20 PSI cold); confirm the automatic fill valve is operating; bleed air from radiators or baseboard heaters if performance was uneven last season; inspect the expansion tank for proper pre-charge pressure; confirm the circulator pumps are operational. For steam heating systems: check the boiler water level and automatic water feeder. Have a licensed plumber service any issues before the heating season begins.

How can I protect pipes in unheated areas from freezing in Ontario?

For pipes in unheated garages, crawlspaces, mechanical penthouses, or near exterior walls: install pipe insulation on cold-water supply lines; install thermostatically controlled electric heat trace on any pipes that could be exposed to freezing temperatures; confirm that mechanical room heating is operational and set to maintain at least 5°C; and drain any pipes that serve areas that will be unheated all winter.

What fall plumbing tasks are required for commercial buildings in Ontario?

Commercial building fall plumbing tasks include: drain and blow out all outdoor hose bibs and irrigation systems; clear roof drain strainers of fall leaf debris before the freeze season; confirm heat tracing is operational on exposed pipes; verify mechanical room heating is working; check that sump pumps are operational before the freeze-thaw cycle of early winter; inspect and clear eavestroughs and downspouts; and confirm the boiler or heating system is ready for the heating season.

What plumbing problems are most common after Ontario winters?

The most common winter-related plumbing problems in Ontario are: frozen and burst outdoor faucets (from connected hoses preventing the frost-free mechanism from draining); frozen pipes in unheated areas or near exterior walls with inadequate insulation; failed heat trace on exposed pipes; and flood damage from sump pump failures during freeze-thaw events. Completing the fall checklist before winter prevents the majority of these issues.

Fall Plumbing Maintenance Checklist for Ontario Properties

Before the first hard frost — typically October in the GTA and southern Ontario, September/October in northern Ontario. Complete outdoor faucet shutoff and irrigation system blowout before the first hard frost event, not after.

For frost-free sillcocks: disconnect all hoses (a connected hose prevents self-draining). For standard hose bibs: close the interior shut-off valve, open the outdoor tap to drain the pipe segment, and leave the outdoor tap slightly open to allow drainage.

Have a licensed irrigation contractor perform a compressed air blowout of all irrigation zones. Book in September or October — schedules fill quickly. Close the irrigation shut-off, remove the backflow preventer if not freeze-rated, and set the controller to off mode.

Fall is a good time if it hasn't been done in 12 months. Annual service before the highest-demand winter season should include sediment flush, anode rod inspection, T&P valve test, and setpoint verification (min 60°C).

Check system pressure (12–20 PSI cold for hydronic systems); bleed radiators if heating was uneven last season; confirm auto-fill valve works; check expansion tank pre-charge; verify circulator pumps are running. Have a plumber service issues before heating season begins.

Install pipe insulation; install thermostatically controlled heat trace on vulnerable pipes and test it before winter; maintain mechanical room heating above 5°C; drain pipes serving areas that will be completely unheated all winter.

All residential tasks plus: verify building heat trace systems; schedule Q4 backflow preventer testing; confirm grease interceptor service records; brief operations staff on emergency shut-off locations; test parking garage and loading dock sump pumps before freeze-thaw season.

Frozen and burst outdoor faucets (from connected hoses); frozen pipes near exterior walls; failed heat trace; sump pump failures during freeze-thaw events. The fall checklist prevents the majority of these issues.

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Fall Plumbing Maintenance Checklist for Ontario Properties

Fall Plumbing Preparation Across Ontario