You touch the thermostat and see 19 °C. The number everyone knows. The so-called “responsible” setting repeated for years through energy campaigns, rising bills, and climate messages. It has become second nature.
But your feet feel cold. Your teenager stays wrapped in a hoodie indoors. Your elderly mother, visiting for the weekend, quietly pulls a blanket over her legs and says she’s fine. You start wondering whether 19 °C is truly a universal comfort point, or just a habit we stopped questioning.
You are far from alone. Across Europe, this winter has sparked renewed discussion among doctors, building specialists, and public health professionals. Their guidance is shifting quietly, and the updated recommendation is not what most people expect.
The long-standing 19 °C rule meets everyday reality
For decades, 19 °C has been promoted as the ideal balance: warm enough for comfort, low enough to reduce energy use. A simple, tidy compromise.
However, the science behind that figure dates back to a very different era. Homes were built differently, daily routines involved more movement, and populations were younger overall.
Today’s homes are better insulated but often more airtight. Many people spend long hours sitting, working at screens, or resting on sofas. At the same time, populations are aging, with more individuals living with circulatory or respiratory conditions that make cooler indoor temperatures harder to tolerate. What felt acceptable decades ago can now feel uncomfortably cold.
Energy poverty has also increased sharply. In many households, indoor temperatures drop to 17–18 °C not by choice, but out of fear of rising energy bills. When experts revisited the evidence, a difficult question emerged: are homes being under-heated, and is health paying the price?
Surveys in the UK revealed a telling gap between advice and reality. When adults were asked about their actual winter settings, living rooms averaged 21–22 °C, even among those aware of the 19 °C recommendation. Daily practice has quietly moved higher.
Public health data reinforced this shift. Hospital admissions for respiratory illnesses, heart issues, and even mental health crises rise during prolonged cold periods. These effects appear not only in extreme cold, but also in homes kept below roughly 20–21 °C over time.
Current guidance indicates that healthy adults should not remain in homes below 18 °C, while older adults and other vulnerable individuals require closer to 20–21 °C for safety.
When comfort and efficiency are considered together, many specialists now converge on a new range: around 20–21 °C in main living spaces. Not excessive, not uncomfortable, but adapted to real human needs rather than slogans.
Seen in that light, 19 °C no longer appears as an ideal target, but as a minimum threshold.
A revised target of 20–21 °C, applied selectively
The updated guidance does not promote one rigid temperature for an entire home. Instead, experts increasingly recommend zoned heating, where warmth is focused on rooms that are actively used.
Living rooms and home-office spaces are now commonly set at 20–21 °C, providing a healthier and more realistic baseline for most adults. Bedrooms, by contrast, can remain cooler, typically between 17–19 °C, which many people find supportive of better sleep. Kitchens, hallways, and transitional spaces may sit lower still, especially when used briefly.
This approach replaces the idea of a uniform temperature with a layered home: a comfortable core surrounded by cooler areas.
In practice, this means using thermostatic radiator valves or smart controls to adjust each room individually. Evening time spent in the living room justifies a higher setting there, while a rarely used guest room can safely remain at 16–17 °C, provided dampness is avoided.
Experts also stress an often overlooked factor: perceived temperature. Cold walls, drafts near the floor, or uninsulated surfaces can make 20 °C air feel significantly colder. The thermostat reading alone does not define comfort; the building envelope plays a crucial role.
Public messaging that clings to a single number overlooks how bodies, homes, and habits vary. The emerging advice reflects this complexity, favouring modestly warmer occupied spaces combined with better control and reduced heat loss.
Heating efficiently at 20–21 °C without driving up costs
The concern about increasing the thermostat is understandable. Energy costs already feel heavy, and each additional degree can seem expensive.
Yet heating specialists note that maintaining a steady 20–21 °C can be more efficient than cycling between very cold and very warm conditions. Heating systems operate best when they run steadily rather than stopping and starting repeatedly.
One commonly recommended strategy is low and slow heating. This involves setting living areas to around 20–21 °C while lowering the boiler’s flow temperature, often to 50–60 °C instead of much higher levels. Radiators remain warm for longer periods, and overall efficiency improves.
Smart thermostats can assist when used thoughtfully. Instead of allowing indoor temperatures to drop sharply overnight, a gentle reduction to 18–19 °C helps avoid energy-intensive reheating in the morning.
Another barrier is emotional rather than technical. Many people feel guilty setting their heating above 19 °C, as though comfort conflicts with responsibility. This often leads to short bursts of higher heat during cold evenings, followed by regret.
Health professionals are clear that long-term exposure to cold indoor environments carries real risks, particularly for children, older adults, and those with existing conditions. Persistent cold is not a virtue and does not represent sustainable living.
More effective savings often come from elsewhere: sealing drafts, insulating lofts, improving windows, maintaining radiators, and closing shutters at night. Small interventions can deliver greater benefits than constant adjustments of half a degree.
As some specialists now frame it, the priority is maintaining a healthy indoor temperature range while reducing waste through better buildings and smarter systems, rather than encouraging discomfort.
- Updated living-area target: around 20–21 °C for most adults.
- Lower temperatures where appropriate: cooler bedrooms and unused rooms kept just above 16 °C.
- Meaningful energy savings: focus on insulation, draft-proofing, and stable settings.
Moving beyond the 19 °C mindset
The 19 °C rule still appears frequently, in older leaflets, casual conversations, and half-remembered advice. Over time, it has shifted from evidence-based guidance to cultural habit.
Current expert thinking is more nuanced and more human. The message is not to ignore energy use, but to stop treating 19 °C as a moral ceiling. Comfort, health, and building quality all matter.
Most people recognise the awkwardness of a living room where guests keep their coats on slightly too long. No one mentions it, yet the discomfort is shared. The revised guidance offers quiet permission to adjust the dial and focus efforts where they make the most difference.
Some households will continue to prefer 19 °C because it suits them or fits their budget. Others will settle at 21 °C and feel noticeably better. The real change lies in moving from one rigid number to a flexible, informed range.
Heating is not only about energy units; it reflects how people live, age, and rest in their homes. Recognising the value of comfort, balanced with efficiency and smarter design, marks a meaningful shift.
The next time you hesitate in front of the thermostat, remember that the 19 °C rule belongs to another time. The goal now is to find a temperature that supports both health and sustainability, shaped by your home and your daily life.
- New target range: approximately 20–21 °C in occupied living areas.
- End of uniform heating: room-by-room settings based on actual use.
- Focus on health and building performance: reduce cold homes through insulation, air-sealing, and smarter controls.
