Home › Plumbing › Burst Pipe

FROZEN PIPES & COLD-WEATHER FAULTS

Burst Pipe

A burst pipe needs immediate isolation. Shut off the water, open taps to drain pressure, protect electrics and contain the leak until repair.

!

Never use a flame, blowtorch or boiling water to thaw frozen pipework

Frozen pipes may already be split. Isolate the supply where possible, open the affected tap slightly and thaw gradually. Keep water away from electrics and be ready for leakage as ice melts.

MOST LIKELY CAUSES

Start with these

Freeze damage Ice expansion splits pipework and fittings.
Corrosion or pinhole failure Older pipe can rupture under pressure.
Impact or drilling damage Mechanical damage can create a sudden leak.
Failed joint or fitting A connection may separate or crack.
◫ Symptom variations Match the fault to cold-weather conditions. ⌄
  • Water spraying from pipe
  • Ceiling or wall floods suddenly
  • Pressure drops sharply
  • Leak began as frozen pipe thawed
  • Water continues after one valve is closed
✓ Quick checks Work safely before thawing or restoring pressure. ⌄
  1. Check whether one outlet, one branch or the whole property is affected.
  2. Inspect exposed pipework in lofts, garages, cupboards and outside walls.
  3. Open the affected tap slightly.
  4. Isolate the water supply if a split is suspected.
  5. Use only gentle, controlled heat.
If flow returns: inspect carefully for leaks before leaving the system pressurised.
If a split or leak appears: isolate immediately and arrange repair.
1 Step 1 — Shut off the main water supply Use gradual heat and keep suspected damaged pipework isolated. ⌄

Process

Close the main stopcock or nearest effective isolation valve.

Success looks like: The pressurised flow reduces or stops.
Escalate when: If isolation fails, call an emergency plumber.
2 Step 2 — Drain the system Use gradual heat and keep suspected damaged pipework isolated. ⌄

Process

Open cold taps and, where appropriate, hot taps after heat sources are off.

Success looks like: Stored pressure and water volume reduce.
Escalate when: Keep water away from electrical fittings.
3 Step 3 — Contain and protect the property Use gradual heat and keep suspected damaged pipework isolated. ⌄

Process

Use buckets, towels and plastic sheeting.

Success looks like: Damage is limited until repair.
Escalate when: Do not rely on temporary tape for a pressurised repair.
⌁ Common causes explained Why pipes freeze and fail. ⌄

A burst pipe needs immediate isolation. Shut off the water, open taps to drain pressure, protect electrics and contain the leak until repair.

Ice expands inside the pipe and can split copper, plastic, joints and valves. The damage may remain hidden until the ice melts and water pressure returns.

⌘ Advanced diagnostics Plumber-level inspection and repair. ⌄
  • Cut out and replace split pipework.
  • Inspect neighbouring frozen sections.
  • Pressure-test before restoring supply.
  • Dry and assess affected building materials.
  • Improve insulation and frost protection.
▣ Parts that may need replacing Common components linked to this fault. ⌄
  • Replacement pipe
  • Repair coupling
  • Isolation valve
  • Pipe clips
  • Insulation
! When to call a plumber Conditions that should end basic troubleshooting. ⌄
  • A pipe has burst or begins leaking as it thaws.
  • The frozen section is concealed.
  • The main stopcock or supply valve is frozen or will not close.
  • Water is near electrical equipment.
  • A loft tank, boiler or unvented system is involved.
  • The property has no water after visible pipework is checked.
? Frequently asked questions Common questions about frozen pipes. ⌄

Can I use a blowtorch to thaw a pipe?

No. Open flames can cause fire, damage pipework and rapidly create steam pressure.

Why does the pipe leak only after thawing?

The ice may temporarily seal a split. Water escapes once the ice melts and pressure returns.

Should I leave a tap open while thawing?

Open the affected tap slightly so melting water and pressure can escape.