Emergency plumbing
Frozen pipe repair
Short answer
If a faucet gives little or no water in freezing weather, a pipe feeding it is likely frozen. Keep the faucet open, apply gentle heat (warm air, a hair dryer, warm towels) starting nearest the faucet, and never use an open flame. If you can't find or reach the frozen section, or it has already split, shut off the main valve and call a plumber.
Updated · Editorial team; not yet technically reviewed
Frozen Pipe Repair at a glance
- Signs
- No water or a trickle at one fixture, frost on exposed pipe, odd smells from drains.
- Thaw safely
- Faucet open, gentle heat, work from the faucet back toward the frozen spot.
- Never
- Use a torch or open flame, or leave a space heater unattended.
- Most vulnerable pipes
- Exterior walls, crawl spaces, attics, garages, and under-sink cabinets on outside walls.
How to thaw a frozen pipe
Open the faucet
Open both hot and cold on the affected fixture. Flowing water helps melt the ice and relieves pressure.
Find the frozen section
Look along exposed pipe in cold spaces: frost, bulges, or a very cold spot.
Apply gentle heat
A hair dryer, a heating pad, warm towels, or a space heater kept at a safe distance. Start close to the faucet and work back.
Keep going until full pressure returns
Then check the length of the pipe for leaks as it thaws; a split often only shows once water flows again.
If the frozen pipe is inside a wall, raising the room temperature and opening cabinet doors may be all you can do. A plumber can locate and thaw it safely.
Why frozen pipes burst
Ice itself rarely splits a pipe at the frozen spot. As ice forms and grows, it pushes water toward the closed faucet, and pressure between the ice and the faucet climbs until the pipe fails, often some distance from the ice. That's why opening the faucet and relieving pressure matters. If a pipe has already burst, follow burst pipe repair steps.
Preventing frozen pipes
- Insulate pipes in crawl spaces, attics, garages and exterior walls; use heat cable rated for pipes where freezing is frequent.
- Seal air leaks near pipes, such as around vents, dryer ducts and sill plates.
- Disconnect garden hoses and shut off and drain outdoor faucets, or install frost-free hose bibs.
- On very cold nights, let a faucet on an exterior wall drip and open cabinet doors under sinks.
- Keep the heat on when you're away; a commonly recommended minimum is around 55°F.
Problems that lead to frozen pipe repair
Common questions
How long does it take for pipes to freeze?
It depends on temperature, wind, insulation and pipe location. Unprotected pipes in unheated spaces are at risk whenever temperatures stay well below freezing for several hours.
Will frozen pipes thaw on their own?
Often, as temperatures rise, but the risk of a burst remains while they're frozen. Thawing gently with a faucet open is safer than waiting.