Pipes & water supply

Frozen pipes

Frozen pipes should be thawed slowly and carefully; the real danger is a hidden crack that only leaks once the ice melts, so shutting off water first is wise if you suspect a break.

Difficulty
Moderate
Time
30 minutes-several hours
DIY cost
$10–$40
Pro cost
$150–$500 (if pipe cracked)

Symptoms

  • No water or a trickle from a specific faucet in cold weather
  • Frost visible on an exposed section of pipe
  • Pipe feels rock solid and cold to the touch
  • Problem started during a cold snap

Likely causes

  • CommonPipe running through an unheated or poorly insulated spacePipes in crawlspaces, attics, exterior walls, or garages are most exposed to freezing temperatures.
  • CommonThermostat set low or heat off in part of the houseReduced heating during cold snaps, especially in vacant rooms, lets nearby pipes drop below freezing.
  • PossibleInadequate pipe insulationPipes without foam sleeves or heat tape in vulnerable areas freeze faster during extended cold.
  • Less commonWind exposure through a gap or vent near the pipeA draft directly on a pipe can freeze it even in an otherwise adequately heated space.

What to do

  1. Keep the affected faucet open slightly so water can flow as soon as the ice starts to melt, relieving pressure.
  2. Locate the frozen section, usually where the pipe is exposed to cold, such as near an exterior wall or in a crawlspace.
  3. Apply gentle heat with a hair dryer, heating pad, or towels soaked in hot water, starting from the end nearest the faucet and working toward the blockage.
  4. Never use an open flame, blowtorch, or other high-heat device directly on a pipe.
  5. Keep the heat source moving and check the faucet periodically for water flow returning.
  6. Once thawed, check the entire pipe length carefully for cracks or splits before assuming it's fully repaired.
  7. To prevent recurrence, insulate exposed pipes, seal drafts near them, and keep cabinet doors open under sinks on exterior walls during cold snaps.

Tools and parts

  • Hair dryer or heating pad
  • Towels
Pipe insulation sleevesSearch: “foam pipe insulation sleeves”

When to call a pro

Call a plumber if you can't locate the frozen section, the pipe doesn't thaw after a couple hours, or you find any cracking once thawed.

Safety

Use caution

Never use an open flame or blowtorch to thaw a pipe; this can ignite nearby materials or cause the pipe to burst suddenly.

Related guides

Operator provides AI-generated troubleshooting information. It can be wrong. For safety-critical, electrical, gas, structural, medical, automotive safety, or other high-risk problems, consult a qualified professional.