Fall Checklist: Getting Your House Ready for a Wet Ontario Winter

Fall home maintenance to prevent water damage comes down to three jobs: stop pipes from freezing, keep the roof and attic from forming ice dams, and make sure rain and melting snow have a clear path away from the house. Most of it takes one afternoon and basic tools. Do it after the leaves have dropped and before the first hard freeze, which in the London area usually means late October into November.

Why winter is hard on Ontario houses

Our winters are wet as much as they are cold. Temperatures swing above and below freezing many times, so snow melts, refreezes and melts again. Rain often falls on top of snow. Water that gets into a small gap freezes, expands and makes the gap bigger. Pipes in cold spots can freeze and split, then leak once they thaw. Almost all of this is predictable, which is why a fall routine works.

Fall home maintenance checklist for water damage: outside

1. Shut off and drain the outdoor taps. Close the shutoff valve inside the house, then open the outside tap and leave it open so the line empties. If the inside valve has a small bleeder cap, open it over a bucket to drain the last bit.
2. Disconnect every garden hose, even from a frost-free tap. A hose left attached traps water in the tap body, and that is how frost-free taps split.
3. Clean the eavestroughs once the trees are bare, and confirm each downspout runs freely with its extension attached.
4. Look over the roof from the ground or with binoculars. Check for missing, curled or lifted shingles and for gaps in the flashing around the chimney, plumbing vents and where a lower roof meets a wall.
5. Check the caulking around windows, doors and anywhere a pipe, cable or vent passes through the wall. Cut out anything cracked or pulled away and replace it with exterior-grade sealant.
6. Clear leaves and debris out of window wells so they can drain.
7. Drain and store the hose reel, sprinklers and any rain barrel. A full barrel will freeze and crack, and its overflow ends up at the foundation.

What to check in the attic before winter

Ice dams start in the attic. Heat leaking up from the house warms the roof deck, snow melts, and the water refreezes at the cold eaves. The ridge of ice that forms holds later meltwater back until it works under the shingles and into the ceiling. The fix is a cold, well-ventilated attic.

• Look for even insulation coverage with no bare or thin patches, especially near the eaves and around the attic hatch.
• Make sure insulation is not stuffed into the soffits. Air has to flow in at the eaves and out near the ridge.
• Confirm bathroom fan ducts run all the way to a roof or wall hood. A duct that ends in the attic dumps warm, wet air onto cold wood all winter.
• Weatherstrip and insulate the attic hatch. It is often the biggest single air leak in the ceiling.
• Look at the underside of the roof boards for dark staining or water marks. Staining found now is easier to deal with than frost and drips in January.

How to keep pipes from freezing

Walk the house and find every water line that runs through a cold space. Common trouble spots are pipes in an attached garage, in a crawlspace, along an outside wall behind a kitchen or bathroom cabinet, and near the rim of the foundation where cold air leaks in. Slip foam pipe insulation over the exposed runs and seal the drafts beside them with caulking or spray foam. Insulation slows heat loss, but it cannot protect a pipe that sits in freezing air for days, so stopping the draft matters more than the sleeve.

On the coldest nights, leave cabinet doors open under sinks on outside walls so room heat reaches the pipes. Keep the thermostat steady. Deep overnight setbacks save little and let cold corners drop further.

Know your main water shutoff

Find the main shutoff valve, usually where the water line enters the basement near the meter. Make sure everyone in the house knows where it is. Turn it off and on once to confirm it works. Old gate valves with a round handle can seize or fail to close fully. If yours will not turn or will not stop the flow, have a plumber replace it with a quarter-turn ball valve before winter. In a burst pipe, the time it takes to shut the water off decides how big the cleanup is.

Last items before the snow

• Pour a bucket of water into the sump pit and confirm the pump starts and empties it.
• Check that the ground along the foundation still slopes away from the house and top up any spots that have settled.
• If the air conditioner or furnace has a condensate line or pump, check that it drains freely.
• Take dated photos of the roof, the basement and the mechanical room. If you ever have a claim, your insurer will want to see the condition before the loss.

Pick a dry Saturday, print this list and work from the outside in. If the attic or basement turns up staining or a damp smell you cannot explain, get it looked at before the freeze, while everything is still easy to reach.

Common questions