Frozen pipes: how to prevent them and what to do

Thaw gently. Never with a flame.

The answer in 2 lines. If no water comes out of a tap in freezing weather, a pipe is probably frozen. Turn off the water at your stop tap first: if the pipe has split, it will leak as it thaws. Open the tap it feeds, then warm the pipe slowly from the tap end with a hot water bottle, warm cloths or a hairdryer on low, never a flame. If a pipe has burst, keep the water off, keep away from wet electrics and call a plumber and your home insurer. Prevention is easy: lag exposed pipes, keep some heating on and fix dripping taps before winter.

The first 3 steps

Turn off the water at your internal stop tap (often under the kitchen sink).
Open the tap fed by the frozen pipe, so water can escape as it thaws.
Warm the pipe gently, starting from the tap end: hot water bottle, cloths soaked in warm water, or a hairdryer on low held away from the pipe.

Stop: danger

Never use a blowtorch, lighter or any flame: fire and burn risk, and it can crack the pipe.
Water near sockets, lights or the consumer unit: do not touch them. If the consumer unit is dry, switch the power off there; if not, keep away and call 999 if there is danger.
Ceiling bulging after a burst in the loft: leave the room and keep everyone out.
Boiler stopped in the cold: it may be a frozen condensate pipe, not your water pipes: see our boiler checks guide.

A pipe has burst

Keep the stop tap off. If the stop tap is stuck or the leak is before it, call your water company's 24-hour leak line (on your bill).
Switch off the boiler or immersion heater if the hot water system is affected, and the power to wet areas if the consumer unit is dry.
Open cold taps to drain the system, catch the water, move valuables.
Take dated photos and videos before you clean up, and keep damaged items.
Call your home insurer ("escape of water") as soon as you can, and a plumber. For an approved plumber, use WaterSafe, the national register of plumbers approved by water companies: enter your postcode and choose one that lists emergency work.
If you rent: tell your landlord straight away, in writing too. Landlords must keep water pipes in repair (Landlord and Tenant Act 1985, section 11). If water is coming into a flat below, tell the neighbour.

Before winter: stop them freezing

Lag exposed pipes in the loft, garage, outside walls and under floors with foam pipe insulation from any DIY shop: match the inside diameter to your pipe (most household pipes are 15 mm or 22 mm). Cover the cold water tank in the loft too, but not underneath it.
Outside tap: turn it off at its inside isolating valve, open it to drain, and fit a cover.
Find your stop tap now and check it turns.
Fix dripping taps: a slow drip can freeze in the pipe.
In a cold snap: keep the heating on low, even when you are out; open the loft hatch a little to let warm air in; open cupboard doors under sinks on outside walls.
Going away: keep the heating on a low or frost setting, or turn the water off at the stop tap and drain the system. Check your insurance policy: some have conditions for empty homes.

More tips: WaterSafe, Anglian Water and CCW.

What not to do

Pouring boiling water directly on a frozen pipe or using a flame.
Leaving the stop tap on while you thaw a pipe that might be split.
Using a hairdryer or heater where water is dripping or the floor is wet.

Who is responsible for which pipe

Inside your home: the owner (or the landlord, if you rent).
The supply pipe from your property boundary into the house: usually the owner's responsibility.
The water main and pipes up to the boundary: your water company. Rules on frozen or damaged meters vary between companies: check your water company's website or call it.

Good to know

Burst pipes often show only when the ice thaws, sometimes hours later: check lofts and outbuildings after a cold spell.
UK insurers paid a record £6.1 billion in home and business property claims in 2025, for all causes including weather, fire, theft and escape of water (ABI, February 2026). Figures for 2026 are not yet published.
Scotland has Scottish Water and Northern Ireland has NI Water; Scotland, Wales and Northern Ireland have their own tenancy laws.

In Newcastle, Graham wakes to no water from the kitchen cold tap after a night at minus 6°C. He turns off the stop tap, opens the kitchen tap and wraps the pipe under the sink, on the outside wall, in towels soaked in warm water. After twenty minutes water trickles out, with no leak. He fits foam lagging that afternoon and leaves the cupboard door open at night.

A made-up story, for illustration.

Bobby

Sources, verification, confidence

Verified on 1 November 2026, for England. Confidence: high for the thawing and burst-pipe steps and the responsibility for pipes; high for the ABI 2025 figure (all property claims, not only burst pipes; a separate burst-pipe figure for 2025 was not found); medium for meter rules and insurance conditions for empty homes, which vary by water company and policy. This guide describes common cases, not a diagnosis.