Frozen & Burst Pipe Repair in Ottawa

Why Ottawa Pipes Freeze

Ottawa's cold season runs roughly from early December to mid-March, and frost has been estimated to reach around 40 inches into the ground in a hard winter – deep enough to freeze a water service line that isn't buried to proper depth, or an exposed line in an unheated crawlspace, garage or exterior wall. A line that freezes once is at real risk of freezing again the same winter unless the underlying cause – insulation, depth, or exposure – is addressed rather than just thawed. The thing most people get wrong is assuming cold alone is the problem. It is usually moving cold air: a gap at the rim joist, an unsealed sill plate, a vent in a crawlspace nobody closed, or an attached garage door left open on a windy night. Air infiltration is what turns a merely cold pipe into a frozen one.

Why the calls come on the warm day

The Split Does Not Leak Until It Thaws

The failure is delayed, which is why the emergency calls cluster on the warm day rather than the cold night. When water freezes inside a closed section it expands, and the pressure that builds ahead of the ice is what splits the pipe, usually somewhere between the ice plug and a closed tap rather than at the ice itself. Copper splits open along its length. PEX will often survive the freeze itself while the brass fittings, valves and shutoffs at its ends crack instead. Either way the split does not leak while it is still full of ice. It leaks the moment the line thaws, sometimes hours after the homeowner has decided the problem sorted itself out.

Locating the Frozen Section

Which fixtures have lost flow tells you roughly where the ice is. Nothing anywhere in the building points at the service entry, the meter or the main run before the first branch. One fixture out with everything else working puts it in that branch, usually where the line passes through an exterior wall or over an unheated space. Cold side out but hot side fine, or the reverse, isolates it to one of the two runs. A bathroom over a garage, a kitchen sink on an outside wall, and a laundry tub in an unheated addition are the three most common locations in Ottawa housing. Then, before applying any heat at all, open the fixture at the end of the frozen run. That gives melt water somewhere to go and relieves pressure as the plug releases, and it is also how you know the moment flow returns.

Thawing is done with controlled heat: warm air on the pipe and the cavity around it, heat blankets, or an electric thawing machine that passes current through metallic pipe. That last one is not an option on PEX or plastic, which is why the pipe material has to be identified before a method is chosen. An open flame is never used, and not only because of the fire risk in a wall cavity. Concentrated heat on a section of pipe with ice on both sides flashes trapped water into steam with nowhere to expand, and that can rupture a pipe that survived the freeze. Underground service lines are their own category, thawed with steam or by a machine rather than by anything reaching them from inside.

Whose line, and what fixes it for good

Stop It Freezing a Third Time

If the frozen line is on the City’s side of the property line, the City will thaw it at no charge. If it is on your side, which is most interior and many exterior residential lines, you are responsible for the cost, and repeat freezes mean repeat charges either from the City or from a private plumber. For a line that freezes more than once, we can assess whether rerouting, added insulation, or a heat trace cable is the more permanent fix. Rerouting is usually the strongest answer, because moving a run to the warm side of the insulation removes the cause instead of managing it. Where that is not practical, sealing the air path matters more than adding pipe wrap, and a thermostatically controlled heat trace covers the sections that cannot be moved. Alongside the rest of our winter plumbing help in Ottawa, that assessment is worth booking in the fall rather than after the second freeze.

What the Repair Costs Depends On

Thawing an accessible line is the cheap end. Cost climbs when the pipe is behind finished drywall, above a ceiling, under a tiled floor or buried outside, because reaching it and putting the finish back is most of the work. A single split in copper is a section replacement. A run that has split in several places, or an older galvanized run that has been freezing and corroding for years, is a repiping conversation rather than a patch. Overnight and holiday rates apply to genuine emergencies, and a burst line at full pressure is one. A pipe that is frozen but has not leaked, in a house that still has water at other fixtures, can often wait for the morning, which costs less and lets the work be done properly rather than in the dark.