She pulled her cardigan tighter and rubbed her hands together, the way her parents used to in their old brick house, repeating the same mantra every winter: “Nineteen degrees is enough, it’s the rule.”
Outside, the sky was that dull winter grey that seems to drain colour from everything. Inside, her seven-year-old padded across the wooden floor in fluffy socks and asked a simple question: “Mum, why is it warmer at school than at home?”
Lara didn’t have a good answer. Just that stubborn “19 °C rule” she’d heard from energy leaflets, TV experts, and half her colleagues. The temperature number felt more like a moral judgement than a setting on a wall.
And quietly, a new idea is starting to replace it.
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The 19 °C rule is fading: what experts are really recommending now
For decades, 19 °C was sold as the golden compromise: low enough to save energy, high enough “not to freeze.” It became a kind of social norm in many European households, a way to show you were both reasonable and responsible. If you said you heated to 21 or 22 °C, you almost felt guilty.
Yet more and more heating experts, building engineers and doctors are quietly moving away from that rigid number. They talk instead about a *comfort band*, where the body and the home actually work together instead of fighting each other.
The surprising thing is this: they now converge on a slightly higher range. **Around 20–21 °C in living areas**, with a few smart adjustments, is increasingly presented as the sweet spot for both real comfort and long-term energy savings.
On a cold January afternoon in Manchester, a local housing association ran a small, informal test in a tower block they’d just renovated. Half the flats were set to a fixed 19 °C. The other half were given a programmable thermostat pre-set to a steady 21 °C in the day and 18–19 °C at night, along with basic draught-proofing.
After six weeks, the engineers compared gas consumption and interviewed residents. The result surprised even them. The “21 °C” flats had not used more energy overall. In several cases, consumption actually dropped, because people stopped secretly cranking radiators to maximum, then opening windows when it got stuffy.
Tenants in those flats also reported fewer coughs, less condensation on windows, and a nicer feeling underfoot on tiled floors. One older resident summed it up in her own way: “At 19, I’m always deciding which room to heat. At 21, I just live in my home.”
On paper, 19 °C sounds efficient. In real life, our behaviour complicates that tidy equation. When we feel chilly at 19 °C, we move less, sit closer to radiators, and often bump the heating up “just for an hour” that turns into several. Short, aggressive heating cycles force boilers and heat pumps to work harder, with worse efficiency.
Experts now insist on another crucial factor: mean radiant temperature. If your walls, windows and floors are cold, your body feels colder, even if the air reads 19 °C. That’s why **a stable 20–21 °C with better insulation and fewer draughts can, paradoxically, cost less** than a patchy 19 °C in a leaky home.
What’s really dying is not the number 19 itself, but the idea that one fixed setting can fit everyone, every building, every health condition. A modern rule looks more like this: a core band around 20–21 °C in living spaces, 17–19 °C in bedrooms, adjusted to your house, your age, and how you actually live.
How to set your thermostat now: the new comfort rule in practice
The specialists who have moved past the 19 °C mantra talk in very concrete terms. Their first recommendation is simple: choose a target range, not a single magic number. For most homes, they now suggest **20–21 °C in the main living area during the day**, especially if children, elderly people or people working from home are there.
At night, or when everyone is out, a gentle setback to 17–18 °C is usually enough. The key is to avoid brutal swings. Instead of heating from 15 °C to 23 °C in a rush every evening, keep your home in a smaller band, so your boiler or heat pump runs calmer and more efficiently.
Engineers also recommend using one room as your “reference space” with the thermostat in a place you actually use, not in a cold hallway you cross twice a day.
On a rainy Thursday in Lyon, an energy adviser visited a young couple living on the top floor of an old building. They complained of high bills and constant shivering. Their thermostat was stuck at 19 °C but the kids’ room felt icy. The adviser walked around with a small infrared thermometer and quickly found the culprits: a draughty window frame and a freezing corner wall behind the bed.
Instead of simply telling them to “turn it down to save money,” he proposed a different strategy. He suggested setting the living room to 20.5 °C during the evening, keeping bedrooms at 18 °C, and spending a modest budget on sealing gaps and adding a thermal curtain. After the changes, the couple reported feeling warmer at the same or slightly lower consumption.
Stories like this are common across Europe. Once people stop treating 19 °C as a sacred line, they start noticing how their homes really behave. And that’s where genuine savings begin.
Why does this higher comfort range not automatically blow up your bills? Part of the answer lies in our bodies. Below roughly 20 °C, many people unconsciously tense their muscles, move less, and feel tired sooner. That low-level discomfort pushes us to compensate in other ways: longer hot showers, portable electric heaters next to the sofa, endless cups of tea just to hold something warm.
From a technical angle, modern condensing boilers and heat pumps often work more efficiently when they run for longer periods at moderate power rather than in short, intense bursts. A home that floats peacefully between 20 and 21 °C with good insulation may need less total energy across the day than one that oscillates between “very cold” and “too hot.”
Doctors working in respiratory and cardiovascular care also point out that for older adults, **a slightly warmer, stable home temperature is protective**. Cold stress at 17–18 °C over long periods is linked to increased hospital admissions in winter. Which makes that single, strict 19 °C target start to look not only obsolete, but sometimes risky.
Simple moves to stay warm, save energy and forget the old rule
The most effective new habit isn’t glamorous: pick your comfort band once, then leave the thermostat alone for a week. For many households, that means trying 20 °C during the day, 18 °C at night, and then gently nudging by half a degree if you genuinely feel chilly or sweaty. Not three degrees in a moment of frustration.
If you have smart thermostats or programmable valves, set schedules that match your real life: wake-up time, work-from-home days, kids’ bedtime. The aim is to keep your walls and furniture from ever getting bone-cold. That way, when your heating runs, it doesn’t need to fight an indoor iceberg.
Small, boring steps add up: sealing draughts around windows, moving a sofa away from a radiator, laying a rug on a freezing floor. Warm feet change how your brain reads 20 °C.
Many people still live with a kind of thermostat guilt, clinging to 19 °C because they feel they “should.” On a psychological level, the number has become almost moral. When you move that number up to 20 or 21 °C, there’s a flutter of anxiety: is this wasteful, selfish, wrong?
Energy specialists know this. They now stress that real efficiency is not about freezing in your living room. It’s about consistency, insulation, and cutting waste nobody notices: heating empty rooms, letting hot air leak under the front door, drying clothes on radiators that never quite warm the space.
We’ve all had that moment when a guest comes over, glances at the thermostat and jokes, “Wow, you like it tropical in here.” The reflex is to defend ourselves. Maybe it’s time to answer differently: “I like my home healthy… and my bills under control.”
One building physicist who works with low-energy homes put it bluntly:
“The obsession with 19 °C made sense when houses were leaky and energy was cheap. Today, it’s outdated. A well-managed 20–21 °C home, with insulation and smart controls, is usually safer, more comfortable, and can be just as efficient in real life.”
To keep things simple, experts often suggest a basic checklist you can actually remember and use, instead of endless rules no one follows. Soyons honnêtes : personne ne fait vraiment ça tous les jours.
- Living room: aim for 20–21 °C when occupied, not more, not less for long periods.
- Bedrooms: 17–19 °C, plus a good duvet and pyjamas, especially for children.
- Night setback: lower by 2–3 °C, not 6–7 °C, to avoid huge reheating costs.
- Health-sensitive people: keep their main room in the upper range, around 21 °C.
- Before changing the number: fix draughts, heavy curtains, rugs. Then adjust half a degree if needed.
A new way to think about warmth at home
The quiet death of the old 19 °C rule isn’t just a technical story. It reveals something deeper about how we see our homes, our bodies, and our responsibilities. For years, cutting the thermostat number felt like the only way to show you cared about the planet and your bills. Now, experts are inviting us to something more subtle, and frankly more human.
Instead of a moral battle between 19 and 21 °C, they picture a home where you move around freely, sleep well, breathe clean air, and don’t need three layers just to answer emails at the kitchen table. They talk about steady warmth, not stifling heat. About using technology to track and smooth your energy use, not punish yourself with cold as proof of virtue.
This new approach raises questions worth sharing with friends, neighbours, colleagues. What if comfort and responsibility were not enemies? What if raising your thermostat by one well-managed degree, while sealing leaks and changing habits, was actually a smarter, more modern form of sobriety? The old number is fading. The conversation about what replaces it is only just beginning.
| Point clé | Détail | Intérêt pour le lecteur |
|---|---|---|
| Nouvelle plage de confort | 20–21 °C dans les pièces de vie, 17–19 °C dans les chambres | Savoir à quelle température viser pour être bien sans gaspiller |
| Stabilité plutôt que yo-yo | Limiter les variations à 2–3 °C entre jour et nuit | Réduire la consommation réelle tout en gardant une chaleur agréable |
| Confort global | Agir sur l’isolation, les courants d’air, les sols et les murs froids | Ressentir plus de chaleur sans forcément monter le thermostat |
FAQ :
- Is 19 °C still a good temperature for heating my home?It can work for some people in well-insulated homes, but many experts now see 19 °C as a lower limit rather than a standard. A range around 20–21 °C in living areas often delivers better comfort and similar or lower real-life consumption.
- Won’t 21 °C automatically increase my energy bill?Not necessarily. If you keep temperatures stable, improve insulation, and stop heating empty rooms, a slightly higher setpoint can lead to equal or lower yearly costs, because your system runs more efficiently and you avoid extreme reheating.
- What temperature is healthiest for children and older adults?Most health bodies recommend around 20–21 °C in the main living area, with bedrooms slightly cooler. For frail or elderly people, keeping their main room near 21 °C reduces cold stress and health risks in winter.
- Is it better to turn the heating off completely when I’m away?For short absences, experts usually advise a small setback (for example 17–18 °C) rather than switching everything off. Letting the home get very cold means you’ll spend more energy reheating walls, floors and furniture.
- How long should I wait before changing my thermostat setting again?After adjusting the temperature, give it at least 24 hours, ideally a full week of similar weather, to judge how it really feels and how your energy use changes. Constantly fiddling with the number makes it harder to understand what actually works.
