When winter brings freezing temperatures, many homeowners face a common but costly issue: burst pipes. Frozen pipes burst not only cut off your water supply but also lead to major leaks, expensive plumbing repairs, and potential structural damage.
To understand how to prevent pipes from freezing and bursting, you first need to know why pipes burst in the winter and what you can do to protect them.
Why Frozen Pipes Burst
The science is simple but serious:
- Water Freezes and Expands: When water inside pipes freezes, it expands by about 9%.
- Pressure Builds: Expansion increases water pressure between the frozen area and a closed faucet.
- Pipes Burst: When pressure exceeds the pipe’s strength, the pipe ruptures, releasing full water pressure into your home.
Pipes don’t always burst where the ice forms. Instead, pressure causes a weak point further down the line to give way, which is why even one pipe freezing can lead to additional frozen pipes and leaks in other areas.
Why Winter Increases the Risk
Cold weather affects plumbing systems in several ways:
- Little or No Insulation: Exposed pipes in attics, crawl spaces, and garages freeze faster.
- Exterior Walls: Pipes along exterior walls are most vulnerable.
- Unheated Interior Areas: Pipes in unheated crawl spaces or garages are exposed to freezing air.
- Garage Doors: Leaving garage doors open in cold weather exposes water supply lines to freezing air.
- Sudden Drops in Temperature: Rapid freezes give water no time to drain, increasing the chance that water pipes burst.
Consumer Reports experts, including John Galeotafiore, recommend keeping the thermostat set to the same temperature day and night to help prevent freezing.
Where Pipes Are Most Likely to Freeze
- Pipes in unheated interior areas like basements and crawl spaces
- Lines running along exterior walls with little insulation
- Water supply lines in garages if garage doors are left open
- Outdoor spigots, hose bibs, and irrigation lines
- Areas with wrapping pipes done poorly or not at all
Warning Signs That a Pipe May Be Frozen
Knowing the signs of frozen pipes helps you act quickly:
- Faucets that produce only a trickle or no water at all
- Frost visible on exposed pipes
- Strange smells from drains due to blocked water flow
- Cold spots on walls where water supply lines run
If ignored, frozen pipes can easily lead to a burst pipe and flooding.
How to Prevent Pipes from Freezing
1. Add Pipe Insulation
Wrap pipes in foam or use heat tape. Both are inexpensive options from your local hardware store.
2. Keep Warmer Air Circulating
Open bathroom cabinet doors or open kitchen cabinets to allow heat around plumbing.
3. Maintain Higher Temperatures
Keep the thermostat set to the same temperature day and night. Don’t let it dip below 55°F.
4. Let Faucets Drip
Allow cold water to drip from faucets during freezing nights. Running water is less likely to freeze.
5. Close Garage Doors
Keep garage doors closed to protect water supply lines and plumbing in attached garages.
6. Disconnect Outdoor Hoses
Drain hoses and shut off outdoor spigots before the first freezing temperatures arrive.
How to Thaw Frozen Pipes Safely
If a pipe freezes, act fast to avoid burst pipes:
- Faucet Open: Keep the faucet served by the pipe open. As ice melts, running water will flow and help melt ice inside the pipe.
- Apply Heat: Use safe methods to apply heat to the frozen area:
- An electric hair dryer
- An electric heating pad wrapped around the pipe
- Towels soaked in hot water
- A portable space heater placed safely nearby
- Avoid Dangerous Methods: Never use propane heaters, charcoal stoves, or flammable materials to thaw frozen pipes. These pose fire and health risks.
- Check Other Faucets: If one pipe freezes, check other faucets for additional frozen pipes.
If you cannot thaw frozen pipes safely, call a licensed plumber immediately.
What To Do If Pipes Burst
A burst pipe requires quick action:
- Shut off the water main to stop the flow.
- Move valuables away from the leak.
- Call a licensed plumber for expert plumbing repairs.
- Use fans and dehumidifiers to dry affected areas and prevent mold.
Remember, water from a burst pipe can spread quickly through your house, damaging floors, walls, and belongings.
Why Professional Help Matters
While DIY steps can help prevent frozen pipes, a licensed plumber offers long-term solutions:
- Proper installation of pipe insulation
- Upgrading to modern plumbing materials
- Installing heat tape on exposed pipes
- Winterizing systems in unheated interior areas
- Replacing sections that have burst or weakened
Professional maintenance ensures your home is better protected every winter.
Final Thoughts
So, why do pipes burst in the winter? It comes down to freezing temperatures, expanding water, and increased pressure inside pipes. Unprotected plumbing in cold weather can’t handle the strain, leading to costly damage.
You can prevent pipes from freezing by adding insulation, keeping garage doors closed, opening bathroom cabinet doors, and letting faucets drip during extreme cold. If a frozen area develops, safely apply heat with an electric heating pad or electric hair dryer.
And if your water pipes burst, don’t wait. Shut off the water supply, keep other faucets open, and call a licensed plumber to handle the repair. With proper preparation and professional support, you can keep your house safe, warm, and dry all winter long.
