A frozen pipe can split open and flood your home the moment it thaws. Learning how to prevent frozen pipes is the cheapest insurance you can buy before an Ontario winter hits.
The steps below take an afternoon, cost almost nothing, and save you from a burst pipe in February.
How to Prevent Frozen Pipes Before Winter Hits
Water expands when it freezes. Trapped inside a pipe, that pressure has nowhere to go, so the pipe cracks. Your job is to keep the water above freezing.
Start with the pipes most at risk. Those are the ones in cold, uninsulated spots.
- Pipes along exterior walls
- Pipes in the garage, attic, or crawl space
- Outdoor faucets and hose bibs
- Lines running through an unheated basement
Wrap these with foam pipe insulation from any hardware store. It costs a few dollars per length and slides right on. For the pipes most likely to freeze, add heat tape rated for plumbing and follow the maker’s instructions.
A burst pipe in a Whitby or Oshawa home can dump gallons of water in minutes. Spending an afternoon now beats a flooded basement later.
Shut Off and Drain Outdoor Faucets
Your outdoor faucets freeze first because they sit right against the cold. A frozen hose bib can crack and leak inside the wall where you will not see it until spring.
Here is what to do before the first hard frost:
- Disconnect and drain every garden hose.
- Find the shut-off valve for the outdoor line, usually just inside the basement wall.
- Close that valve.
- Open the outdoor faucet to let the leftover water drain out.
- Leave the outdoor faucet open through winter.
If you have frost-free hose bibs, you still need to disconnect the hoses. A connected hose traps water and defeats the frost-free design.
Keep Heat Moving Through the House
Cold air pools in corners, cabinets, and rooms you keep closed. Pipes hiding in those spots are the ones that freeze even when the furnace is running.
Open the cabinet doors under your kitchen and bathroom sinks on cold nights. This lets warm room air reach the pipes behind them. On the coldest nights of an Ontario winter, let a faucet drip slightly. Moving water is much harder to freeze than still water.
Never set your thermostat below 13 degrees Celsius in winter, even when you are away. If you travel, ask someone to check the house. A furnace that quits during a cold snap can freeze every pipe in the place within hours.
Sealing the cold air out
Find the gaps where cold air sneaks in near your pipes. Look around the rim joist in the basement, where pipes pass through exterior walls, and near the dryer vent.
Seal small gaps with caulk and larger ones with spray foam. Keeping that frigid air out does more than you might expect to keep a pipe from freezing.
What to Do If a Pipe Freezes Anyway
Sometimes a pipe freezes despite your best work. Caught early, you can often thaw it before it bursts.
The warning signs are easy to spot. A faucet that gives only a trickle on a cold morning usually means ice in the line. Frost on a visible pipe is another clue.
If you find a frozen pipe, act fast:
- Open the faucet that pipe feeds, so water can flow once it melts.
- Warm the pipe with a hair dryer or a space heater kept clear of anything flammable.
- Start near the faucet and work back toward the cold spot.
- Never use an open flame or a blowtorch. That can split the pipe or start a fire.
If the pipe has already burst, shut off your main water valve right away. Then read our guide on what to do when a pipe bursts and call us.
When to Call a Plumber
You can handle insulation and a slow thaw yourself. Some situations need a licensed plumber, and putting them off only makes the damage worse.
Call right away if you cannot find the frozen section, if a pipe has split, or if water is leaking behind a wall. A frozen pipe inside a wall is hard to reach safely, and forcing it can cause more harm.
Our emergency plumbing team answers 24/7 across Ajax and Durham Region. After-hours emergency calls start at about $149 for the service call and diagnosis, and you get a flat quote before any repair starts. If you have a recurring weak spot, our leak detection and pipe repair service can find and fix the vulnerable line before next winter.
Do not wait for a small problem to become a flooded basement. Call us at (647) 560-2817 or request a free estimate and we will get a plumber to your door fast.
Frequently Asked Questions
At what temperature do pipes freeze?
Pipes are at risk once the air around them drops below -6 degrees Celsius, though exposed pipes against an exterior wall can freeze sooner in a wind. The danger climbs the longer the cold lasts. During an Ontario cold snap, uninsulated pipes in a garage or crawl space are the first to go.
Should I let my faucets drip in cold weather?
Yes, on the coldest nights. A slow drip keeps water moving through the pipe, and moving water is much harder to freeze than still water. Let both the hot and cold sides drip on faucets fed by pipes along exterior walls or in unheated spaces.
How do I thaw a frozen pipe safely?
Open the faucet that the pipe feeds, then warm the frozen section with a hair dryer or space heater, starting near the faucet and working toward the cold spot. Never use an open flame or blowtorch. If you cannot reach the pipe or it has already split, shut off the main valve and call a plumber.
Will insulation alone stop pipes from freezing?
Insulation slows heat loss but does not add heat, so it is not a full fix on its own. For pipes in very cold spots, pair foam insulation with heat tape and keep the area sealed against drafts. The goal is to keep the pipe above freezing, not just wrapped.
How much does it cost to fix a frozen or burst pipe in Ajax?
After-hours emergency calls start at about $149 for the service call and diagnosis. Minor pipe repair starts at about $199, and the final cost depends on the location and access. We give you a flat quote before any work begins, even at night.