Seasonal guides · 3 min read
Freeze-thaw cycles are hard on a house. An exterior tap, a sump discharge line and an outdoor condenser all want ten minutes of attention before the ground goes solid.
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Every Calgarian knows the weather turns on a dime. One week is crisp autumn afternoons, the next is minus twenty-five, and then a chinook arrives and undoes it overnight.
That cycle is harder on residential systems than a steady cold would be. A neglected garden tap or an exposed sump line becomes an expensive basement problem in a single night, and almost always on the coldest one.
Before the ground freezes solid, here is what is worth doing.
Outdoor hose bibs are the most common source of hidden winter water damage. Water trapped inside the spigot freezes and expands backward into the wall cavity, splitting the line where nobody can see it until it thaws.
Disconnect every garden hose
A hose left attached holds water against the tap and defeats every other step below. Do this one first, and do it before the first hard frost rather than after it.
Shut the indoor isolation valves
Each exterior tap has a dedicated shut-off inside — usually in the basement or on the utility room ceiling, near where the line runs out through the wall. Close it completely.
Drain both ends
Go outside and open the faucet fully. Back inside, unscrew the small bleeder plug on the isolation valve into a bucket and let the section between them empty. Leave the outside tap open all winter — a pipe with nothing in it cannot split.
Blow out the sprinkler lines
Underground irrigation manifolds sit inside the frost zone in Alberta. Compressed air, cleared fully, before the first hard freeze. A system drained by gravity alone usually is not empty.
An outdoor condenser is built for the cold, but it still wants a proper shutdown.
Cut the power at the outdoor disconnect
There is an electrical disconnect box beside the unit. Switching it off stops the system starting up on an unseasonably warm chinook day, which is how compressors get damaged — the oil is too cold and too thick to protect anything.
Clear the debris
Leaves, grass clippings and twigs out of the housing and away from the aluminium fins. They hold moisture against the metal all winter.
Cover the top only
Never wrap the whole unit in plastic. It traps condensation against the coil, which rusts it, and it makes an excellent winter home for mice. A breathable top cover or a board across the upper fan grille is all it needs — the point is falling icicles and snow load, not weather.
This applies to an air conditioner, not a heat pump. A heat pump uses the same outdoor unit to heat the house in winter, so cutting power to it in October would leave you without heating in January. If you are not certain which you have, leave the disconnect alone and ask whoever services it.
A few minutes in the utility area now prevents the two in the morning version of the same job.
Check the sump pump discharge
Disconnect any corrugated roll-out hose on the outside end. If water freezes inside that extension, the pump dead-heads against the ice during a thaw and burns out its motor at precisely the moment you need it.
Insulate the drafty runs
Cantilevered bump-outs, cabinets on exterior walls, unheated utility spaces. Foam pipe sleeve over anything exposed. These are the same places that freeze every year, so if one froze last winter, start there.
Find the main shut-off
Usually beside the water meter where the line enters the house. Make sure everyone in the house knows where it is and that it actually turns — a seized valve discovered during a burst is a much worse night than a seized valve discovered in September.
Two things worth doing when an extreme cold warning comes across the foothills:
These lists are built from what each firm states on its own website, so they are who says they do the work rather than our recommendation of who does it best.