The most expensive water losses in South Georgian Bay are not caused by anything unusual. They are ordinary supply-line failures in buildings nobody is standing in.
A line at mains pressure does not stop. In an occupied house that is a bad afternoon. In a chalet visited at weekends it is a bad month, and in a cottage closed from October it can be five. The failure is identical. The only variable is the discovery date, and the discovery date is the entire cost difference.
| Found after | What is typically wet | What the work becomes |
|---|---|---|
| Under 6 hours | Finishes and the room it happened in | Extraction and drying |
| 1–3 days | Cavities, insulation, the floor below | Partial removal, then drying |
| 1–3 weeks | Structure, and growth has started | Removal, remediation, rebuild |
| Over a month | Everything below the failure, plus contents | A rebuild with a drying phase in it |
Why this region produces so many of them
Two reasons, and they compound.
The first is occupancy. A great deal of the housing on and below the escarpment through The Blue Mountains and Craigleith is visited rather than lived in, and Wasaga Beach empties almost entirely for the winter. A large share of the buildings we work in are dark on any given weekday in January.
The second is the freeze-thaw pattern. Environment Canada normals at the nearest reporting station put the Collingwood area at roughly 92 days a year that cross the freezing point and come back. Each one of those is a cycle for whatever is sitting in an unheated space, and the shoreline along Nottawasaga Bay and the escarpment behind it do not experience them on the same days.
Where the failures actually happen
Almost never in the middle of a heated room. The pattern is consistent enough to check against a list:
- A supply line run inside an exterior wall, particularly on the weather side.
- A crawl space with a vent that was never closed in the autumn.
- A laundry in an unheated garage.
- A kitchen or bathroom on a slab addition with services under it.
- A run passing through an unconditioned space between two heated ones — the commonest of all on a multi-level chalet.
- An outside tap where the interior isolating valve was never closed and drained.
If you own a seasonal building, walking that list once with a torch is a better use of an hour than almost anything else on this site.
What a proper shutdown looks like
Water off at the main. Then drain the system down and leave the valves open, so nothing anywhere can trap pressure between a plug and a closed fixture. Traps get protected with plumbing antifreeze rather than water.
Or low heat, if draining is impractical. Held above freezing everywhere, including the spaces on the list above, which frequently means opening cabinet doors under sinks on outside walls and leaving interior doors open so warm air reaches the ends of the building.
A low-temperature alarm that reaches a phone. Not a thermostat you trust. The failure mode that matters is the power going out during the storm that brought the cold, and an alarm that depends on the same power and the same internet connection reports nothing at all.
Somebody physically in the building at a stated interval, and the interval written down. This is not only prudence. Many policies covering seasonal and unoccupied buildings make freeze damage conditional on the water being shut off and drained, or on heat being maintained and the building checked at a stated frequency. Read that clause in October rather than in February — whether to claim water damage on your insurance covers what happens when a wording and a reality do not match.
The check nobody makes
Everybody inspects during the cold snap, because that is when it feels urgent.
The burst appears at the thaw. Ice forming in a pipe does not usually split it — the pressure trapped between the plug and a closed fixture does, and the water only escapes once the plug melts. So the busiest run of calls in this trade is the first mild afternoon after a hard cold spell, and it lands on properties that were checked two days earlier and found perfectly fine.
A property inspected during the cold and not after the thaw has effectively not been inspected. Of everything on this page, that sentence is the one worth keeping.
If you find it late
Do not start drying the middle of it. After weeks, the working assumption has to be that materials in contact with the water have failed rather than merely got wet, and that growth is established behind the finishes.
The useful first step is establishing the boundary of the affected area, because that answer decides whether this is drying with some removal or a rebuild with a drying phase inside it. Frozen and burst pipe damage sets out how that assessment runs, and what to do in the first hour covers the part that still applies even when the water is long gone.
One further thing worth doing in the same week: read the October checks that prevent a spring loss, because the property will be closed again next year and the list is short.