How to Prevent Frozen Pipes (and What to Do If They Freeze Anyway)

Ontario winters are beautiful, until your plumbing decides to freeze.

Few things cause as much panic for homeowners as discovering a pipe that’s turned into an icicle. Frozen pipes can burst without warning, spilling hundreds of litres of water in minutes and leaving behind costly damage.

The good news? With the right prevention and quick action, you can protect your home and your peace of mind, even during the coldest days of the season.

Here’s everything you need to know about how to prevent frozen pipes and what to do if they freeze anyway, straight from the experts at Guest Plumbing & HVAC.

Why Do Pipes Freeze in the First Place?

Pipes freeze when the temperature around them drops below 0°C and the water inside begins to solidify.

As water turns to ice, it expands, and since pipes can’t stretch, the pressure builds until the pipe cracks or bursts.

In Ontario, this most often happens in:

• Unheated basements, crawl spaces, or garages
• Exterior walls or poorly insulated sections of the home
• Attics or cold storage areas
• Outdoor hose bibs and sprinkler lines

The risk increases during long cold snaps, especially when homes are left unattended or the heat is turned down too low.

How to Prevent Pipes from Freezing in Winter

Preventing frozen pipes comes down to one simple principle: keep them warm and keep the water moving.

Here are the most effective steps to protect your plumbing this winter:

1. Insulate Exposed Pipes

Exposed or poorly insulated pipes are the first to freeze.

Use foam pipe insulation sleeves, fiberglass wraps, or heating cables on pipes in:

• Basements and crawl spaces
• Attics and garages
• Under kitchen or bathroom sinks on exterior walls

Tip: Focus on any area where you can feel a chill. That is where your pipes feel it too.

2. Keep a Consistent Temperature Indoors

Fluctuating indoor temperatures can cause cold spots and condensation around pipes.

• Keep your thermostat set to no lower than 17°C (63°F) — even at night or when you’re away.
• Open cabinet doors beneath sinks to allow warm air to circulate.
• Avoid turning off your heat entirely, even if you’re leaving for a few days.

If you travel in winter, consider installing a smart thermostat to monitor and adjust your home’s temperature remotely.

3. Disconnect and Drain Outdoor Water Lines

Outdoor faucets, hoses, and sprinkler systems are extremely vulnerable.
Before the first freeze:

• Disconnect garden hoses.
• Drain and shut off outdoor taps from the inside shut-off valve.
• Blow out irrigation lines if you have an underground sprinkler system.

These simple steps prevent water from sitting in outdoor lines. It’s the number one cause of burst pipes in early winter.

4. Let Faucets Drip on Frigid Nights

When the temperature drops below -15°C, allow a slight trickle of cold water to flow from faucets connected to exposed pipes.

Moving water is far less likely to freeze, and the small increase in your water bill is negligible compared to the cost of a burst pipe.

5. Seal Drafts and Insulate Vulnerable Areas

Cold air sneaking into your home can create freezing conditions in unexpected spots.

• Seal gaps around windows, doors, and electrical outlets.
• Use weatherstripping or spray foam around pipe entry points.
• Add insulation to basements, crawl spaces, and attics.

A warmer home means safer plumbing, and lower heating bills, as well.

What to Do If Your Pipes Freeze Anyway

Even with precautions, extreme cold can still cause trouble. If you turn on a tap and no water comes out, act fast and stay calm.

Here’s what to do:

Step 1: Turn Off the Main Water Supply

Immediately shut off the main valve to stop additional water from flowing into frozen or burst sections.
This helps prevent flooding if the pipe cracks while thawing.

Step 2: Locate the Frozen Section

Frozen pipes often feel hard or frosty to the touch. Common locations include:

• Exterior walls
• Basements near foundation vents
• Under kitchen or bathroom sinks

If you can’t find the section, call a licensed plumber right away.

Step 3: Thaw the Pipe Safely

Never use an open flame, such as a torch or lighter to thaw pipes.
Instead:

• Use a hair dryer, space heater, or electric heating pad.
• Start warming the pipe near the faucet first, then work toward the frozen area.
• Keep the faucet open so melting ice and steam can escape.

If multiple pipes are frozen or you suspect a burst, shut off power to the affected area and call a professional immediately.

Step 4: Check for Leaks

Once water flow returns, carefully inspect for cracks or dripping water.
Even a hairline fracture can lead to serious water damage once pressure builds back up.

Guest Plumbing & HVAC offers 24/7 emergency plumbing service across Ontario for exactly these situations. Fast, reliable help when you need it most.

Long-Term Prevention Tips for Ontario Homeowners

After handling a frozen pipe emergency, it’s worth investing in long-term protection:

• Schedule annual plumbing inspections to identify weak spots.
• Add pipe insulation in all unheated areas.
• Install a smart leak detection system that sends alerts to your phone.
• Have your HVAC system serviced annually to ensure balanced home temperature.

With a few proactive steps, you can prevent another winter disaster.

FAQs:

Q: What temperature do pipes start freezing?
A: Water begins freezing at 0°C, but most household pipes are at risk once outdoor temperatures stay below -6°C for more than a few hours.

Q: How can I tell if a pipe has burst?
A: Look for reduced water pressure, puddles, or damp drywall. A sudden spike in your water bill is also a warning sign.

Q: Should I keep my water running all winter?
A: No, only let faucets drip slightly during extreme cold snaps to keep water moving.

Stay Protected This Winter with Guest Plumbing & HVAC

Frozen pipes are stressful, but they’re also preventable.

With professional maintenance, expert plumbing inspections, and 24/7 emergency support, Guest Plumbing & HVAC helps Ontario homeowners stay warm, dry, and worry-free all winter long.

If you suspect your pipes are frozen or want to prevent them from ever freezing,
Contact Guest Plumbing & HVAC today to schedule a winter plumbing inspection.