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Ice does its damage quietly and posts the bill with the thaw. Here's how to keep pipework liquid through a cold snap — and the safe way to rescue the pipe that caught you out.
Tap slowed to a dribble in freezing weather? That's the classic sign. Close the stopcock as a precaution, open the affected tap, and warm the frozen run gently from the tap end back — hairdryer on low, warm towels, a heated room. Never a naked flame or blowtorch, ever. Pipe already split? Keep the water off and ring 020 4577 2888 any hour to be connected with a local plumber.
Freezing weather plus one starved tap is ice until proven otherwise. Find the cold run before you warm anything.
The tell is timing: a tap that ran fine yesterday and dribbles the morning after a hard frost. The pipes that catch it live in the cold margins — lofts, garages, outbuildings, external walls, and the long supply runs rural properties out by Claudy or Eglinton carry in from the road. Trace the starved tap's pipework towards those cold spots; frost on the outside of a pipe, or a section noticeably colder than its neighbours, marks the blockage.
Before thawing anything, close the stopcock. Ice can split copper as it expands and then seal its own damage — you won't know whether the pipe survived until the plug melts, and with the mains off, a split becomes a puddle instead of a flood.
Gentle heat, tap end first, patience throughout. The blowtorch stays in the shed — permanently.
Open the affected tap so melting water has somewhere to go, then work heat along the pipe starting nearest the tap and moving back towards the blockage: a hairdryer on its lowest setting, towels soaked in warm water and wrapped round the pipe, a hot water bottle held against it, or simply heating the room and waiting. Expect it to take a while — slow is the method working, not failing.
What's off the menu: naked flames, blowtorches, heat guns on full, boiling water poured straight on. They can damage the pipe and its joints, they're a fire risk anywhere near loft timbers and insulation, and rapid heating can crack what gentle heat would have saved. If the run is buried somewhere unreachable, or nothing moves after a patient hour, ring rather than escalate.
Lagging, a ticking-over boiler, and knowing your stopcock. The cheapest insurance in all of plumbing.
The north-west's soft, damp winters are exactly the trap: mild for weeks, then a hard frost sweeps in off the hills and finds every unlagged pipe at once. Foam lagging from any DIY shop, fitted on a dry autumn Saturday to the pipes in lofts, garages and outbuildings and along external walls, is the cheapest plumbing work you'll ever commission — especially on the long rural supply runs that feel a freeze hardest.
In a proper cold snap, keep the heating ticking over low rather than fully off — overnight, and in an empty house too, because a few degrees of gas costs small change against a burst. Fix dripping taps before winter (a steady drip can freeze a waste pipe solid), leave loft hatches ajar in bitter weather so house warmth reaches the tank space, and make sure everyone at home can find and turn the stopcock before the night they need to.
Water off, and it stays off. Thawing a burst pipe with the mains on just books your flood in for an hour's time.
If you find a split, a bulge or a weep along the frozen run, leave the stopcock closed, open the cold taps to drain the pipework, and move anything you value out from under the route. A split in a loft deserves extra suspicion: water follows the timbers and can appear a room away from the damage, so check the ceilings below for darkening or sag.
Then ring, and say where the pipe runs and what it feeds. The burst pipes guide covers the full sixty-second drill — electrics, temporary patches, and whose side of the boundary the fault sits on.
Yes — on its lowest setting, kept moving, working from the tap end back towards the blockage. It's the gentleness that makes it safe. What's never safe is a naked flame, a blowtorch or boiling water poured straight onto the pipe: all of them can damage the pipe and its joints, and a flame near loft timbers is a fire risk on top.
Ticking over low, yes — it's one of the cheapest ways to keep pipework above freezing, especially in homes with pipes in lofts or against external walls. The few degrees cost small change next to what a burst pipe and the clean-up afterwards would cost, and the same logic applies to a house left empty in winter.
The ones in the cold margins: lofts, garages, outbuildings, external walls, and the long outdoor supply runs that rural properties carry in from the road. Anything unlagged in an unheated space is a candidate — which is exactly the list to walk round with foam lagging on a dry autumn Saturday.
Keep the stopcock closed, open the cold taps to drain the system, and don't thaw anything with the mains on — the flood only starts when the ice melts. Move valuables clear, watch the ceilings below a loft run, and ring to be connected with a local plumber.
The main page — the triage board and the areas this line covers.
Go to home →The sixty-second triage for escaping water.
Read the guide →Pressure drops, no heat, error codes — and the gas rule.
Read the guide →Pressure, timer, tripped switch, diverter valve — the checks before the call.
Read the guide →The signs, the stopcock test, and when a damp patch turns urgent.
Read the guide →What to try, what never to pour, and when it's NI Water's sewer.
Read the guide →No invented prices — how charging works and what to ask first.
Read the guide →Ring any hour to be connected with a local plumber covering Derry and the villages around it — and say where the pipe runs.
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