Scotland's winters are hard on pipework, and Edinburgh's mix of Victorian tenements, older suburban housing and exposed rural properties all have their own weak points. A frozen pipe is a nuisance — a burst one, caused by ice expanding inside it, can flood a property in minutes. Here's what to do before the cold snap hits, and what to do if you're already too late.
Why pipes freeze — and why they burst
Water expands by around 9% as it turns to ice. In a sealed pipe, that expansion has nowhere to go, so pressure builds until the pipe splits — usually not at the frozen section itself but at a weaker point nearby. The damage often isn't obvious until the ice thaws and water starts pouring out, which is why so many frozen pipe callouts happen a day or two after the coldest night, not during it.
Where pipes are most at risk
The pipes most likely to freeze are the ones outside your home's heated envelope:
Pipes in lofts, especially near eaves and outside walls
Pipes in unheated garages, outbuildings and cellars
External taps (outside taps) and their supply pipes
Pipework running through exterior walls, common in older Edinburgh tenements and villas
Pipes under suspended timber floors in older properties
Five things to do before the cold snap
Lag exposed pipes. Foam pipe insulation is cheap and takes an afternoon to fit in a loft. It won't stop a determined freeze but buys crucial hours.
Insulate outside taps. A foam external tap cover costs a few pounds and prevents one of the most common frozen-pipe callouts we see.
Know where your stopcock is. If a pipe does burst, being able to shut off the water supply immediately is the single biggest factor in how much damage you get. Check it turns freely before winter, not during an emergency.
Keep heating on low overnight during cold snaps. A constant low background heat (even 12–15°C) keeps pipework inside the heated envelope above freezing far more reliably than switching heating off and on.
If you're away, don't turn the heating off completely. Leaving a property unheated during a cold snap is one of the most common causes of the burst pipes we get called to — set a frost-protection setting on your thermostat instead.
If a pipe has already frozen
Turn off the stopcock feeding that pipe as a precaution, then:
Open the affected tap slightly to relieve pressure as it thaws
Gently warm the pipe with a hairdryer on low, or warm (not boiling) water on a towel, starting from the tap end and working towards the blockage
Never use a naked flame, blowtorch, or heat gun directly on a pipe
If you can't reach the frozen section, or the pipe has already split, stop and call a plumber
The clearest sign is a tap that produces little or no water, sometimes with frost visible on an exposed section of pipe, or a strange smell coming from a drain or tap as trapped odours can't escape past the blockage.
You can gently warm an accessible pipe with a hairdryer on a low setting or warm towels, working from the tap end towards the blockage. Never use a naked flame or blowtorch. If the pipe is hidden in a wall or you can't reach it, or if it has already split, turn off your stopcock and call a Gas Safe registered plumber.
Pipes typically start to be at risk once outside temperatures fall below freezing for several hours, especially overnight. Unheated spaces like lofts, garages and external walls are most at risk even when the rest of the house is warm.