Frozen pipe — how to thaw it safely
⚠️ Never use a blowtorch or open flame to thaw frozen pipes. You risk causing the pipe to burst and starting a fire.
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Most likely cause & what to check
Locate the frozen section — check exposed pipes in the loft, under the floor, in the garage, or on external walls. The pipe will feel extremely cold and you may see frost on the outside.
Turn off the main stopcock before attempting to thaw. If the pipe has already cracked, thawing it with the water on will cause a flood.
Open the tap at the end of the frozen section — this releases pressure and gives the water somewhere to go once thawed.
Apply gentle heat to the frozen section: wrap the pipe in towels soaked in hot water and replace them as they cool. A hair dryer on its lowest setting works well on accessible pipes. Start at the tap end and work back toward the main supply.
Never use a naked flame, blowtorch, or heat gun at high temperature. The sudden change causes the metal to expand unevenly and can cause the pipe to crack.
If the pipe is under the floor or in a wall and you cannot access it, call a plumber. They have specialist thawing equipment.
Once thawed, restore the water supply slowly and check carefully for leaks along the entire section. Even pipes that don't burst immediately may have developed micro-cracks that will fail later under pressure.
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