One night your street is quiet, the next morning the pavements sparkle like a pastry and half the neighbourhood is on the phone to a plumber. The worry sits where bills do: right behind the fridge of your mind, humming away.
I was standing in a hallway in Leeds last January, boots squeaking, breath fogging, when the homeowner flicked the thermostat with a kind of hope you can hear. The place had that unkind winter hush. No ticking, no gurgle from the radiators. Just the thin creak of pipes inside walls that suddenly feel very flimsy. *We’ve all had that moment when warmth becomes a number on a dial.* A number that feels too small for the risk. And here’s the thing: there is one number that makes sense.
The single setting that outsmarts the freeze
Here’s the headline your wallet will actually like: **set your thermostat to 13°C (55°F)** during a cold snap, especially when you’re sleeping or away. It’s the sweet spot that keeps water moving just enough to stop ice crystals forming, without paying for a mini-sauna you never enjoy. That number sits on the right side of physics and the right side of your energy bill. Anything lower starts flirting with risk in draughty corners and uninsulated runs.
Think of the house as a tiny weather system. The hallway might read 12°C, but behind the washing machine, along an outside wall, the air can be several degrees colder. A friend in York found that out the hard way after Christmas. They’d nudged the stat to 10°C to “save a bit” while visiting family. A northerly wind, a kitchen cabinet against a cold wall, and a quiet pipe elbow froze, then burst as the day warmed. The repair bill hurt more than a week of gentle heating ever would.
Water freezes at 0°C, yes, but pipes don’t wait to hit zero to cause mischief. Thin copper next to a brick skin loses heat fast. Wind over external walls ramps that up. At 13°C indoors, you leave a buffer for those colder micro‑zones. You also give your boiler short, efficient runs instead of long, gas-guzzling recoveries from near-freezing rooms. The maths is dull, the result isn’t: lower peak demand, steadier comfort, fewer surprises behind the plasterboard.
How to hold 13°C without burning cash
Flick your heating to a constant 13°C overnight and when you’re out. Let it cycle in short pulses. Many smart thermostats call this “eco”, “away”, or “frost protect”, but check the actual number — frost modes can sit as low as 5–7°C, which protects the boiler, not your kitchen pipes. If you’ve a spare room or north-facing study, open the doors so the hallway thermostat reads the house, not just one cosy bubble. That single gesture evens things out.
Small moves stack up. Crack the kitchen cabinet doors where sink pipes run along external walls. Leave interior doors ajar so warm air drifts. In a biting spell, a slow drip from a tap on the longest run keeps water moving and pressure off the line. Let’s be honest: nobody actually does that every day. When the forecast says minus five and windy, it’s worth the five seconds before bed. And if the loft houses tanks or pipes, a little extra insulation over them, not under them, helps the whole network stay friendly.
There’s a reason old-school plumbers bang on about thermostats in draughty halls: the reading lies. If the stat lives above a radiator or gets sun at noon, your 13°C might be fantasy. Move the stat or use a remote sensor in a representative spot — central, shaded, about 1.5 metres up.
“You’re not heating rooms,” says one veteran emergency plumber. “You’re buying time for thin pipes in cold places. Thirteen degrees buys a lot of time.”
And for the visual thinkers, here’s a pocket checklist you can save:
- Thermostat at 13°C (55°F) during cold snaps and trips away
- Open kitchen/bathroom cabinet doors on external walls
- Drip the furthest tap in severe freezes
- Keep interior doors ajar to balance temperatures
- Insulate exposed or loft pipes; fit cheap foam sleeves
Why 13°C works in the real world
Heating is less about the number on a dial than the gaps in your house. At 13°C, most UK homes with cavity walls and basic loft insulation keep internal pipe runs above 2–3°C even when the world outside bites hard. That’s the safety margin you’re buying. If your place is all sash windows and single brick, the same principle holds, you just give the setting a nudge — 14–15°C — for brutal nights, then bring it back.
People often ask if a “burst” happens while it’s frozen or when it warms. It’s the warm-up that betrays you. Ice blocks a section, pressure builds behind it, and once thaw arrives, the split lets go. That’s why a steady 13°C is your friend. It trims the peaks and troughs so your system isn’t yo-yoing from fridge to sauna. Your boiler sips instead of gulps. Your radiators make soft noises, not desperate ones. And behind the sink, nothing cracks with a groan you’ll never forget.
Edge cases matter. Flats with risers on outside walls, holiday cottages left silent, garden rooms with thin roofs — all of these are more vulnerable. That doesn’t bin the 13°C rule, it just adds context. A cheap digital thermometer in the coldest corner tells a crisp truth. If that corner sits within 8–10°C while the stat reads 13°C, you’re golden. If it doesn’t, you now know why that cabinet door and a gentle overnight drip earn their keep.
A human-sized plan for the next cold snap
You don’t need a manifesto. You need a number, a couple of habits, and the calm that follows. Set the stat to **13°C (55°F)** for the nights and the days you’re out. Open the spaces where pipes hide. Give the furthest tap a lazy blink of water when the forecast looks grim. That’s it. The magic is dull on purpose.
We’ve all been there with the best intentions and a thousand tabs open about insulation types and boiler curves. Breathe. Pick the one change that actually happens in your life. That might be moving the thermostat, not the temperature. It might be five minutes fitting foam sleeves on the pipes you can see. Tiny wins, stacked.
There’s an economy to it that feels old-fashioned and kind. You’re warming a place just enough that it looks after itself while you sleep. **Not cosy, not punishing — just safe.** And on a mean January morning when you pad into the kitchen and the tap runs like normal life, you’ll know you nailed the number without wrecking your bill.
Cold brings out strong opinions. Some swear by blasting the heating twice a day, others by switching it off unless they’re shivering. The middle road here isn’t glamorous, but it’s sturdy. Thirteen degrees hums along, spending pennies to save pounds. It leaves room for the quirks of your home — the north wall, the windy corner, the loft hatch that never quite shuts — and treats them with a little grace.
Neighbours will share stories, and they matter. Ask where their coldest spot lives. Borrow a gadget thermometer and test your own. Tell the friend who always forgets the utility room that the thermostat isn’t a badge of toughness; it’s a guardrail. Share the number. Someone will scoff. Another will quietly set theirs to 13°C and wake up grateful. That small kindness might be the warmest thing you do this winter.
| Point clé | Détail | Intérêt pour le lecteur |
|---|---|---|
| Thermostat à 13°C (55°F) | Maintien de la température pour éviter la congélation des tuyaux sans surconsommation | Réduit le risque de dégâts coûteux tout en maîtrisant la facture |
| Équilibrer l’air | Portes intérieures et placards ouverts, capteurs placés au bon endroit | Améliore la précision du chauffage et protège les zones froides |
| Petits gestes par grand froid | Goutte-à-goutte sur le robinet le plus éloigné, isolation simple des tuyaux | Ajoute une marge de sécurité lors des nuits polaires |
FAQ :
- What’s the best thermostat setting to stop pipes freezing?Set it to around 13°C (55°F) during cold snaps and when you’re away. It keeps water moving and temps stable without overspending.
- Is it cheaper to leave the heating on low or turn it off and on?For freeze prevention, a steady low setting costs less than reheating a near-frozen house and lowers burst risk.
- Do I still need to drip taps?Only on severe nights, and mainly the longest run on an external wall. It’s a belt-and-braces move for very cold, windy spells.
- Where should the thermostat live?Central hallway or similar, away from radiators and sunlight, about 1.5 m high. A remote sensor helps if your layout is tricky.
- What if my home is very draughty?Keep the same principle but nudge to 14–15°C on the coldest nights. Add simple pipe insulation and open cabinet doors to balance temps.
