Cause · seasonal, and conditional

Frozen pipes in Canada: the one exclusion that catches people out

This is a Canadian page. Freeze-thaw is the seasonal driver that does not exist in most of the markets these pages get copied from, and the insurance treatment has a condition attached that is unlike anything else on this site.

A pipe that freezes and bursts is normally a covered peril. But the Insurance Bureau of Canada lists among what is not covered: “frozen pipe damage if adequate heating precautions were not maintained”. The peril is in. Failing to keep the heat on is what takes it out.

A note on why this page exists and is not a money page: burst pipe runs about 260 searches a month in Canada at a cost per click of $0.00 — nobody is advertising against it. We wrote it because Canadian winters make it a real question, not because it sells anything.

The condition inside the cover

“If adequate heating precautions were not maintained” is the whole page. It is the only peril here where the policy asks something of you in advance and withdraws if you did not do it.

What counts as adequate is not a number this site can give you, because it is set in your policy wording and it varies. But the situations where it comes up are entirely predictable, and they are worth naming:

• A cottage or second property left unheated over winter.
• A house left empty during a long absence with the thermostat turned down to save money.
• A rental or vacant property between tenancies.
• A furnace that failed while nobody was there to notice.

Most policies impose specific requirements for vacant or unoccupied properties — commonly either maintaining heat, or draining the plumbing system, plus having someone check the property at a stated interval. Those requirements are in your wording and a broker can read them to you in five minutes. That is a five-minute conversation worth having in October rather than in January.

Which pipes actually freeze

Not the ones in the heated middle of the house. The ones in the parts of the building envelope that were never really inside it.

Exterior walls. Supply lines run in an outside wall, especially where insulation is thin or a cavity was never filled. The kitchen sink on an outside wall is the classic.

Unheated crawl spaces and attached garages. A garage with a laundry sink or a hose bib is a standard freeze location.

Attics. Where plumbing was run above the insulation line during a renovation.

Outdoor taps. The single commonest freeze failure in Canadian housing, and the single easiest to prevent: a hose left connected over winter holds water against the valve and the pipe behind it freezes inside the wall.

Crawl space and rim joist areas. Where a draught from a vent or a gap crosses a pipe run.

The pattern is that freezing happens where cold air reaches a pipe, which is nearly always a draught rather than a temperature. Sealing the draught is usually less expensive and more effective than insulating the pipe.

Thawing a frozen pipe without making it worse

If a tap gives nothing and the weather has been cold, assume a freeze.

1. Open the tap it feeds. Leave it open. This gives the melt somewhere to go and relieves pressure as the ice releases.
2. Find your main shut-off before you start. If the pipe has already split, the split only becomes obvious when the ice thaws — that is the moment the flooding starts, and you want to be standing next to the valve.
3. Warm it gently, from the tap end back towards the frozen section. A hair dryer, a heat lamp, towels soaked in hot water. Working from the tap end means the meltwater has an escape route instead of being trapped between two plugs of ice.
4. Never use an open flame. Blowtorches in wall cavities start house fires, and this is the most common way a frozen pipe becomes a catastrophic loss.
5. If you cannot reach it, stop. A pipe frozen inside a wall or under a floor is a plumber's job, and a plumber costs far less than the wall.

Once water is flowing, check the whole run. Ice can split a pipe in a place that only starts leaking once the pressure comes back.

If it has already burst

A burst supply line delivers water at mains pressure continuously. Volume, not contamination, is the problem, and the first minute matters more than anything else on this page.

1. Main shut-off, immediately.
2. Open the lowest taps in the house to drain what is in the system.
3. Cut power to affected areas at the panel if water is anywhere near electrical.
4. Photograph before anything is moved.
5. Call your insurer, then a restorer. Your policy obliges you to limit the damage once you know about it — see duty to mitigate — and waiting for permission to start drying is not what that duty means.

The water is clean to start with, which is Category 1 under ANSI/IICRC S500. Volume carries it further than a dirtier, smaller loss would go, so the drying scope is frequently larger than the visible damage suggests — under floors, into wall cavities, down into the level below.

Before you go away for the winter

The single highest-value list on this page, because it is the scenario where the exclusion actually bites.

Keep the heat on. This is the one that decides whether you have cover. Turned down is fine if your wording allows it; off is the version that causes arguments.

Or drain the system properly. Water off at the main, system drained, and — if the property will be genuinely cold — the traps dealt with. Half-draining is worse than not draining.

Disconnect outdoor hoses and shut the interior valves to the outdoor taps. Five minutes, every autumn, prevents the most common freeze failure in the country.

Open cabinet doors under sinks on outside walls. Free, and it lets room heat reach the pipes.

Have someone check the property. Many policies require this for an unoccupied property, at a stated interval. A furnace that quit on 2 January and was found on 20 January is a very different loss from one found on 3 January.

Read your own wording on vacancy. Ask your broker what your policy needs from you and write the answer down.

Questions people actually ask

Where to read next

• Ice dams, the other cold-weather failure
• What you are obliged to do once you know
• How a Canadian water claim runs
• Every cause, side by side