Winter
Frozen pipes in stone tenements
Frozen pipes in a tenement flat need a slow thaw: shut the stop valve, open the cold taps but never the hot, and warm the frozen section with a heated cloth, never a flame.
By the Pipes Up the Stair site team · how pages are checked · Updated
A tap that gives a cough and nothing else on a January morning usually means ice somewhere in the pipe. Thawed slowly, most frozen pipes come back without damage. Rushed, they split.
The advice here on water pipes comes from Scottish Water. Boiler condensate pipes are a different thing, with different advice, covered on our page about the frozen condensate pipe.
How often does Edinburgh freeze?
Often enough to plan for. The Met Office's 1991–2020 averages give Royal Botanic Garden Edinburgh 42.68 days of air frost a year and Gogarbank, out west, 48.01. December is the frostiest month at both: 10.40 days at the Botanics and 10.63 at Gogarbank, with a December mean minimum of 1.57°C at the Botanics.
- 48.01 daysGogarbank, whole year
- 42.68 daysBotanic Garden, whole year
- 10.63 daysGogarbank, December
- 10.40 daysBotanic Garden, December
What should you do the moment you find a frozen pipe?
Shut off the water and open the cold taps. Scottish Water says to turn off the stop valve immediately and open all COLD taps to drain the system, but never to turn on the hot taps. Its advice warns that a hot water cylinder could collapse. If you don't know where the valve is, see finding your stopcock.
How do you thaw a frozen water pipe safely?
Gently, with a heated cloth. Scottish Water's advice is to check for leaks first and then, if it is safe, gently heat any frozen sections with a heated cloth wrapped around the pipe.
What if the pipe has split?
Then it becomes a burst as soon as it thaws. Keep the stop valve shut, switch off the boiler and immersion heater, keep water away from electrics, and follow burst pipe first steps. Warn the flat below.
Which pipes in a tenement are most at risk?
The ones in unheated places. Pipes and tanks in a roof space, a stair cupboard or against an outside wall get no warmth from the flat's heating, and a flat left empty over Christmas has none at all. A shared pipe running through the close is common property of the flats it serves, so lagging it is a decision for the owners together.
How do you stop pipes freezing in the first place?
Insulate, and keep a little heat on. Home Energy Scotland says insulating pipes and water tanks is one of the simplest and cheapest ways to protect them in cold weather. Where heating lacks a frost setting, it suggests a 10°C thermostat setting, with the programmer on or running for 24 hours.
If you're away, Home Energy Scotland suggests asking someone to check the flat, stop any dripping taps and make sure the frost settings are working.
What if you rent?
Tell your landlord or letting agent as soon as a pipe freezes, and say whether you've shut the water off. Lagging, frost settings and any repair to the pipes are for them to arrange; shutting the stop valve and opening the cold taps is still up to you.
42.68
air frost days a year, Royal Botanic Garden
Source: Met Office
10.40
frost days in a Botanics December
Source: Met Office
Asked on the stair
Can you use a hairdryer on a frozen water pipe?
Scottish Water's advice for water pipes names only a heated cloth, so that is what this page suggests. Advice from boiler makers about condensate pipes is separate and doesn't apply here.
Why only the cold taps?
Scottish Water's advice is to open the cold taps to drain the system and never the hot, because of the risk to a hot water cylinder.
Does a frozen pipe always burst?
Not always, but check for leaks before you thaw, and keep the stop valve shut until you're sure.
Is lagging in the close the factor's job?
If the building has a factor, raise it with them. If not, the owners decide together under their title deeds and the Tenements (Scotland) Act 2004.
Should the heating stay on overnight in a cold snap?
If there's no frost setting, Home Energy Scotland suggests 10°C with the programmer on. Use your own system's frost protection if it has one.
Where this comes from
- Advice on frozen or burst pipes — Scottish Water (archived copy of its page): stop valve, cold taps, heated cloth, no flame
- Protect your pipes this winter — Home Energy Scotland: insulation, 10°C, going away
- Royal Botanic Garden Edinburgh averages — Met Office: frost days, minimum temperatures
- Edinburgh Gogarbank averages — Met Office: frost days
- Tenements (Scotland) Act 2004, section 3 — legislation.gov.uk: shared pipes