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Salt air and hard frosts don't come often here, which is exactly why they catch households out. The drill is short — read it before you reach for the kettle.
Tap won't run in a cold snap — what do I do? Close the stopcock first, as insurance, before you know whether the ice has split the pipe. Then thaw gently from the tap end back — a hairdryer on low, or towels soaked in warm water — and never a flame or boiling water. If the pipe has already split, stop and ring 020 4577 2888 instead of continuing to thaw it.
Frozen water expands, and a split pipe often doesn't show itself until the thaw. Shut the stopcock before applying any heat, purely as insurance.
A pipe can freeze solid without splitting, or it can freeze and crack quietly, with the ice itself plugging the gap until the moment it melts. From the outside, a frozen-but-intact pipe and a frozen-and-split one look identical, which is exactly why the notice is not "try to thaw it" but "close the stopcock, then thaw it." If a split is waiting under the ice, you want the mains already isolated when the water finally gets somewhere to go.
The stopcock is usually under the kitchen sink, a brass valve on the incoming pipe turned clockwise until it stops; many properties also carry an outside stop valve near the boundary as a second option. With it closed, you can thaw the pipe at your own pace, and if a split does turn up, you've already done the one thing that matters most.
Start nearest the tap and work back towards the blockage — never the reverse — using a hairdryer on low, warm (not boiling) towels, or simply raising the room temperature.
Thawing from the tap end first gives the meltwater somewhere to escape as you go; starting in the middle of a frozen run traps expanding meltwater between two plugs of ice, which is how a marginal crack becomes a serious one. Work steadily, testing the tap every few minutes, and keep any hairdryer moving rather than parked on one spot, particularly on plastic pipe, which softens under sustained concentrated heat.
Towels wrung out in warm water and wrapped around the pipe work almost as well and carry less risk of overdoing it — replace them as they cool. Electric heaters and warm air blown gently into a loft hatch or under-sink cupboard can also do the job over a longer, unattended stretch, which suits an overnight freeze better than standing with a hairdryer for an hour.
No naked flame, no blowtorch, no boiling water poured directly on, and no hot water bottle held hard against one spot. Concentrated heat is how a frozen pipe becomes a burst one.
A blowtorch or open flame near any pipe is never the answer, on any material — it can scorch timber behind the pipe out of sight, melt plastic pipe outright, or cause a sudden pressure spike in the trapped meltwater that finishes the crack the frost started. Boiling water poured straight from the kettle carries the same risk on plastic and can shock a copper joint too.
If a pipe is genuinely stubborn and gentle heat over a reasonable stretch of time isn't shifting it, that is the point to stop and ring rather than escalate the heat source. A plumber has tools built for exactly this job, and a Carrickfergus night is rarely so cold that a few extra hours waiting for help causes lasting harm once the stopcock is already shut.
Lofts, garages, outbuildings, external walls, and outside taps are the usual victims — anything sitting outside the heated part of the house.
Older terraces near the town walls sometimes route pipework through cold spaces added on later — a rear scullery, an unheated return room — that never got proper lagging when the rest of the house was modernised. Newer estates up around Woodburn tend to have better-insulated pipework as standard, but garages and utility rooms built as cold extensions can still catch a run of frost off guard.
Out along the shorefront and on Islandmagee, exposed outside taps and long supply runs to outbuildings feel a cold snap first and hardest, simply because more of the pipework sits outdoors or in structures without central heating. Rural properties towards Ballycarry and Straid with older farm outbuildings share the same exposure. If your household falls into any of these patterns, that pipework is the first place to check when the forecast turns sharp.
Foam pipe lagging from any hardware shop, fitted before the first frost, is the cheapest plumbing job a household will ever do.
Pre-slit foam pipe insulation simply clips around exposed pipe and costs little; an afternoon spent in the loft, garage or under an outbuilding sink fitting it is time well spent against a much worse night later. Give particular attention to any pipe running along an external wall, through an unheated extension, or out to a garden tap — those are consistently the pipes that freeze first.
Two more habits cost nothing: leave loft hatches and under-stairs or under-sink cupboard doors slightly open during a hard freeze, so a little of the house's warmth reaches the pipework inside, and if a property is going to sit empty over a cold spell — a holiday let along the shore, a second property, a house between tenants — either leave the heating on low or have the water turned off and the system drained. An empty, unheated house in a hard frost is where frozen pipes turn into burst ones most reliably.
A frozen pipe usually follows a hard frost and affects one identifiable run — a tap that worked yesterday now dribbles or refuses entirely, and the pipe itself may feel icy cold or show frost on the outside if it's exposed. An airlock tends to appear without any frost involved and often clears itself when the tap is opened fully for a minute or two. If the cold snap lines up with the timing, treat it as frozen and follow the stopcock-first routine.
Yes, on its lowest heat setting, kept moving rather than held in one spot, and always working from the tap end back towards the blockage. Plastic pipe tolerates gentle warmth well; what damages it is concentrated heat from a naked flame or a hairdryer left blasting one point for too long. Move it steadily and check progress by trying the tap every so often.
No. Once a pipe has split, thawing it with the mains still connected simply schedules the flood for later, once the ice blocking the split finally melts. Keep the stopcock closed, don't attempt to thaw that section, and follow the full standing orders on the burst pipes notice instead — it starts at the same stopcock but the next steps differ.
Anything outside the heated envelope of the house: pipework in a loft, garage or outbuilding, pipes running through an unheated extension, outside taps, and any long exposed supply run to a rural property. Shorefront and coastal properties along the Lough and out on Islandmagee often have more exposed outdoor pipework than inland streets, simply because of how the houses and outbuildings are laid out.
The main notice — how the line works and the waters it covers.
Go to home →Close the stopcock before all else — the full standing orders.
Read the notice →Pressure, error codes, oil and gas — and the gas standing order.
Read the notice →What to attempt, and when it's NI Water's sewer instead.
Read the notice →How charging works and the questions to put before work starts.
Read the notice →Pressure, controls, the immersion — checks in order.
Read the notice →Damp patches, slipping pressure and the stopcock test.
Read the notice →Stopcock closed, heat applied gently, no flame in sight? If it still won't shift — or it's already split — ring any hour and raise a local plumber covering Carrickfergus and the Lough shore.
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