How to stop frozen pipes in a UK cold snap

Prepare the pipes before a cold snap

British Gas, updated 23 October 2026, says water expands as it freezes and can burst a pipe. It cites the Association of British Insurers (ABI): insurers settled roughly 12,000 weather-related burst pipe claims in 2023, with the average claim worth more than £17,000. That figure is the ABI’s, as British Gas quotes it. This site has not checked the ABI publication itself.

On insulation, British Gas says pipe lagging and tank jackets are sold at most DIY stores, and that you should measure the pipes and tanks first. Cover outside pipework (including bends, valves, fittings and outside taps), pipes in unused lofts, garages and basements, and water tanks in those cold spaces. It also says to have the boiler serviced, preferably in warmer months, and to keep windows closed, seal draughts and use draught excluders.

If pipes or tanks are in an unheated loft, British Gas says open the hatch during icy weather so warm air from downstairs can rise. If they are inside cupboards, open the cupboard doors so warmer air can circulate. And keep the thermostat at at least 7°C even when nobody is home.

A dripping tap does not protect the pipes

British Gas calls it a myth that leaving a tap dripping in icy weather stops pipes freezing. It says a leaky tap can freeze the drain, so water backs up to the sink and overflows. Taps should be fully off, and a tap that keeps dripping should be repaired.

If you are away

British Gas says it is worth turning the water off at the stopcock if you will be away for more than a few days. After that, it says you might drain the system by running the taps until they are empty, then close the taps again. The heating advice on the same page still stands: at least 7°C, even if you are not at home.

Know the stopcock before you travel. British Gas says to clear the area around it so you can reach it, and to use it immediately if you spot a leak.

If a pipe freezes

The steps in this section are British Gas’s, from its “Frozen or burst pipes” page, also updated 23 October 2026. They are general precautions, not a repair method for every house.

British Gas says warning signs include gurgling when the heating is on, a boiler that will not turn on, little or no water from the taps, and a sink or toilet that drains slowly. On the prevention page it also lists frosty or wet exposed pipes, bubbling or whistling from the system, and damp patches or rings on walls or ceilings.

It says to find the frozen pipe. On a modern condensing boiler that is often the plastic condensate pipe that leaves the boiler and goes outside. Any outdoor pipe, and pipes through lofts, basements and cupboards on outside walls, can freeze.

To thaw it, British Gas says slowly pour hot — but never boiling — water over the frozen pipe, and place a hot water bottle on it. If you are not sure, it points to its own video rather than a faster method.

If a pipe bursts or leaks

Again, this is British Gas’s list from the same 23 October 2026 page. A burst is not always a flood: British Gas says a slow leak can still damage the home and the electrics. Signs it names include trouble with water flow or pressure, marks on walls or ceilings, bulging walls or ceilings, and damp patches on the floor.

British Gas says: turn the stopcock off straight away and do not turn it back on until a plumber has fixed the leak; switch the central heating off too. If the leak is outside the property and you cannot stop the water, contact the water supplier. Then open all the taps, let them drain until nothing is left, and turn them off. Soak up escaped water with old towels.

If electrics may be wet, British Gas says turn the power off at the mains, let them dry completely, and have a qualified electrician check them before they are switched back on. Call the home insurer — it says most have a 24-hour emergency line — and take photos and find receipts or other proof of purchase. Then call a fully qualified plumber. British Gas says a temporary bind of cloth or heavy-duty tape will not last and is not a substitute for that repair.