Temperature & Freeze-Risk Observation

The honest answer is that it depends on the season, the property and — critically — what your own insurance policy says. There is no universal standard, and anyone who gives you a single number without asking about your policy is guessing.

That said, the practical logic is straightforward. The damage from most vacant-property failures is proportional to how long they run undetected, so the visit interval is effectively a cap on your worst-case outcome. A leak found after three days and the same leak found after three weeks are very different events.

In practice, weekly is the most common cadence for an Alberta property during the heating season, with owners increasing to twice weekly or every 72 hours during extreme cold. Through summer, weekly or biweekly is common. Properties with known risk factors — poly-B plumbing, an aging hot water tank, a history of basement water, or no water shut-off — warrant more frequent visits than a newer, lower-risk property.

The number that actually matters is the one in your policy. Many policies contain a required check interval during extended absences, and some specify who must perform it. Call your insurer or broker and ask directly before you leave.

Water freezes at 0 °C, but pipes inside a building do not freeze the moment the air outside hits that figure. What matters is the temperature at the pipe, which depends on where it runs, how well that space is insulated, how long the cold persists, and whether wind is driving heat out of the assembly.

A pipe in a heated interior wall may be fine at −30 °C outside. A pipe in an uninsulated exterior wall, an unheated garage, or a crawlspace can freeze with the interior at a nominally reasonable temperature, because the pipe is not experiencing the interior temperature.

The commonly cited threshold for concern is a sustained outdoor temperature below about −6 °C, with risk rising sharply as temperature drops and duration extends. Wind matters a great deal — it accelerates heat loss from the building envelope.

The practical approach is to identify the vulnerable locations in your specific property rather than watching a single number: exterior walls with plumbing, unheated garages, basements with poor insulation, rooms above unheated spaces, and anywhere with a history of freezing. Those are the places a visit should check.

The most commonly recommended minimum for an unoccupied home in a Canadian winter is around 15 °C, though recommendations range from about 13 °C to 18 °C. Some insurance policies specify a figure — if yours does, that number governs, not a general recommendation.

The reasoning behind keeping it that high rather than lower: the thermostat reads the air temperature at one location, usually a hallway on the main floor. Temperatures elsewhere in the building — exterior walls, the basement, above the garage, in a bathroom on a corner — run meaningfully colder. Setting 15 °C at the thermostat may mean 8 °C or lower where the plumbing actually is.

Setting it much lower to save on heating is a poor trade. The savings over a winter are modest; the cost of a single burst supply line is not.

A few practical points. Leave interior doors open so heat circulates. Open cabinet doors under sinks on exterior walls. Keep registers open in every room, including ones you would normally close off. If the property has a smart thermostat, set a floor rather than a schedule, and check that any away mode does not drop below your intended minimum.

And ask your insurer whether your policy specifies a minimum temperature during absences. Several do.

The building starts cooling at a rate determined by its insulation, air sealing, the outdoor temperature and the wind. A well-built modern house in moderate cold may lose only a few degrees a day. An older house during a −30 °C wind event can approach freezing internally within a day or two.

The consequence is not a cold house — it is frozen plumbing. Once interior temperatures at vulnerable locations reach freezing, supply lines begin to freeze, and the failure typically shows itself when the ice thaws and water starts running.

This is why visit frequency during cold events matters more than visit frequency generally. The difference between finding a heating failure after two days and after two weeks is the difference between a service call and a restoration project.

On a monitored property the sequence is: the failure is found on a visit, documented, you are contacted, and a licensed HVAC contractor is dispatched under whatever authorisation you have set in advance. Setting that authorisation before you leave is what allows it to happen at 8 PM on a Sunday rather than after an email exchange across time zones.

Connected temperature sensors can shorten detection further and are a sensible supplement — though they only tell you something is wrong, and somebody still has to go to the property.

Yes, and the sensors are still worth installing. They solve different halves of the same problem.

Sensors shorten the gap between a failure and knowing about it, which is the single most valuable variable in vacant property. A temperature sensor turns a heating failure from something found on the next visit into something found within the hour.

What they cannot do is act. A leak sensor cannot close a valve, clear snow off a furnace vent, photograph a ceiling stain so you can see whether it is growing, or let a plumber in. They also depend on a chain — mains power, internet, router, hub, cloud service, battery — that a vacant property breaks more often than an occupied one, and a dead sensor is indistinguishable from a quiet house.

The genuinely risky version is reducing visit frequency because the house is "monitored", when the monitoring stopped reporting six weeks ago. Set the cadence on the assumption the sensors might be offline, and treat their alerts as a bonus.