Simple Ways to Prevent Frozen Pipes in Winter

Cold snaps can arrive quickly in the UK, and when they do, exposed pipes are often the first casualty. A frozen pipe is more than an inconvenience – it can split, burst, and release hundreds of litres of water into your home before you notice. The good news is that most frozen pipe incidents are preventable with a few simple checks. As a family-run plumbing and heating team, we've seen the same avoidable problems year after year, so here are the practical steps we recommend to protect your supply before temperatures drop.

Know Where Your Stopcock Is – and Check It Works

If a pipe does freeze and burst, your first job is to stop the water. That means finding your internal stopcock before you need it. In most homes it's under the kitchen sink, but it can also be in a downstairs cloakroom, under the stairs, or near the front door. Turn it clockwise to close, and check it actually stops the flow – old valves can seize. If it won't budge, call a plumber now rather than during an emergency. Also locate your outside stopcock (often under a small metal cover near the boundary) in case you need to isolate the supply at the mains. Show everyone in the house where these are, and keep the area clear.

Lag Pipes in Cold Spots

Any pipe in an unheated space is at risk: lofts, garages, cellars, outbuildings, and under suspended floors. Even pipes inside kitchen and bathroom cupboards can freeze if the room is cold and the cupboard door is kept shut. Foam pipe lagging is inexpensive and easy to fit. Measure the diameter of your pipes, buy the correct size, and slide it on. Pay attention to joints, bends, and valves – these are the first places to freeze. For extra protection, wrap lagging with waterproof tape at elbows. Don't forget cold water tanks in the loft: insulate the tank itself, but leave the area underneath it uninsulated so any warmth from the house can rise. Also lag the ball valve and overflow pipe. If you have a hot water cylinder in an airing cupboard, a cylinder jacket will keep heat in and reduce the risk of the cupboard dropping below freezing.

Keep a Low Background Heat

The most effective defence is to keep your home warm, even when you're out or asleep. Set your thermostat to at least 12–15°C and leave it there. It costs a little more in gas or oil, but far less than repairing a burst pipe. If you have a conventional boiler, set the programmer to come on for short periods. For combi boilers, a frost stat should protect the boiler itself, but it won't protect pipes elsewhere. Open the loft hatch on very cold days to let warmth rise, and leave internal doors ajar so air circulates. If you're going away for more than a few days, either leave the heating on a low setting or drain the system down completely – a plumber can do this properly. Don't rely on just turning the water off at the stopcock; water left in pipes can still freeze and expand.

Don't Forget Outside Taps and Boiler Condensate Pipes

Outside taps are a common weak point. If yours has an isolation valve inside, turn it off and open the outside tap to drain any remaining water. Fit an insulated tap cover for extra protection. Boiler condensate pipes are another frequent culprit: they run outside to a drain, and a frozen blockage will shut your boiler down. Lag the pipe with foam, increase the diameter where possible, or fit a trace heating kit. If your boiler has a condensate siphon, keep it clean. For extra peace of mind, pour a little warm water down the condensate pipe's outside end during a cold snap – but never boiling water, which can crack plastic.

If a Pipe Freezes, Thaw It Gently

If you turn on a tap and nothing comes out, or you hear a strange gurgling, you may have a frozen pipe. First, turn off the stopcock and open the nearest tap to relieve pressure. Then thaw the pipe slowly, starting from the tap end and working back towards the tank or boiler. Use a hot water bottle, warm towels, or a hairdryer on its lowest setting. Never use a blowtorch, naked flame, or boiling water – rapid heating can crack the pipe or cause a steam explosion. If you can't reach the frozen section or the pipe has already split, turn off the water and call a qualified plumber. Don't try to thaw pipes under floors or in confined spaces yourself. A family-run plumbing and heating team will have the tools and experience to fix it safely, usually the same day.