Experts question the 19 °C rule for home heating

For decades, the temperature of 19 °C has been prescribed as the standard reference for domestic heating in France, a threshold that has almost become synonymous with energy savings and reasonable comfort. Yet, this historical standard born from past energy sobriety measures is now being questioned by industry specialists. Technological advancements, changes in lifestyles, and a better understanding of thermal comfort suggest that an adjustment towards slightly higher temperatures would be more relevant. In a context where energy prices remain a major concern for many households, rethinking the ideal temperature for home heating is no longer a mere theoretical debate but a practical issue with concrete repercussions.

Recent research, notably reported by recognized sources such as Journal du Geek or Presse Citron, encourages abandoning this rigid standard in favor of a more nuanced and personalized approach. Manufacturers like Viessmann, Saunier Duval, and De Dietrich are now adapting their regulation systems and fittings to these new recommendations, offering better temperature management room by room.

The 19 °C Rule: A Historical Heritage Now Outdated

The threshold of 19 °C was generalized in the 1970s, during the oil crisis, as a compromise between comfort and energy savings. At that time, the insulation of domestic housing was often inadequate, and heating systems were far less efficient than those known today. This recommendation aimed to limit energy consumption while ensuring an acceptable level of warmth in homes.

The energy and technological context has changed significantly since then. Now, buildings benefit from enhanced insulation and heating systems that incorporate advanced technologies, particularly thanks to brands like Chaffoteaux, Ferroli, and Atlantic. These innovations allow for better heat distribution, reduce thermal losses, and provide much more precise regulations. The rigid rule of 19 °C no longer reflects these advancements.

Moreover, this fixed limit does not take into account the diversity of climatic zones, lifestyles, or the specific needs of occupants. An elderly person, for instance, will often need a higher temperature to feel comfortable, while a young professional may prefer a cooler atmosphere. The one-size-fits-all standard proves to be unsuitable for each individual’s real comfort.

The impact on health should also be emphasized. Temperatures that are too low increase the risk of colds, circulatory disorders, and even respiratory complications among vulnerable individuals. In this sense, strict adherence to 19 °C can lead to more disadvantages than advantages in certain situations.

Here are some reasons explaining why the 19 °C rule is now being questioned:

• Political origin rather than scientific: established during an energy crisis without specific scientific basis.
• Evolution of housing: better insulation standards and superior energy performance alter thermal needs.
• Diversity of lifestyles: activities, clothing, and habits vary from one household to another.
• Health consequences: a too-cold environment can harm occupants’ well-being.

Changing Factors	Impacted Element	Consequences
Enhanced thermal insulation	Reduced heat loss	Less need for continuous heating
Modern equipment (Deltadore, Thermor)	Fine temperature regulation	Room-by-room adaptation possible
Diverse lifestyles	Subjective temperature	Heating personalization needed
Knowledge of thermal comfort	Multiple parameters (humidity, air circulation)	More nuanced recommendations

Understanding the Scientific Criteria Behind the Ideal Temperature for Heating

Thermal comfort extends far beyond a simple number set on a thermostat. It is a complex science that takes several parameters into account. In addition to temperature, thermal sensation is influenced by:

• Relative humidity: air that is too dry or too humid alters the feeling of warmth.
• Air circulation: cold drafts can create an intense feeling of cold.
• Level of physical activity: a stationary person will feel the cold more quickly.
• Clothing: thick or light clothing, depending on the season and habit.

Experts such as Brad Roberson, cited by Ouest France, emphasize that 20 °C is now a more suitable temperature for living spaces. This shift of just one degree may seem negligible, but it has a significant impact on maintaining body temperature, preventing feelings of cold, and the excessive use of extra layers of clothing.

Raising the temperature to 20 °C also helps limit condensation on walls, a key factor in preventing mold. This phenomenon is common in older or poorly ventilated homes, and insufficient heating promotes the emergence of these harmful nuisances for health and building structure.

On the other hand, strict adherence to the 19 °C rule can lead to hidden energy overconsumption, due to resorting to auxiliary solutions or artificially raising the temperature to compensate for discomfort.

Thermal Comfort Criteria	Influence on Sensation	Practical Consequences
Ambient temperature	Overall feeling	Personalized adjustments needed
Relative humidity	Impacts on sensation of warmth or coldness	Optimize ventilation
Air circulation	Cold drafts or stagnation of warm air	Proper insulation and limiting infiltrations
Physical activity	Metabolism variations	Adapt temperature to usage
Clothing	Personal thermal insulation	Advice to occupants on indoor dressing

Beyond traditional advice, it is essential to consider a differentiated temperature management for each room, to reconcile comfort, health, and energy savings. This approach is enhanced by modern systems that facilitate fine and targeted regulation.

Towards Personalized Heating: Adapting Temperature Room by Room in 2025

One of the major turning points in the field of domestic heating is the rise of differentiated management, which consists of modulating the temperature according to the use and passage in each room. This concept is gaining ground thanks to technological advancements and an increasing awareness of economic benefits.

Here are some guidelines to understand this approach:

• Living spaces (living room, dining room): ideally at 20 °C to ensure optimal comfort during calm activities or in the presence of several occupants.
• Bedrooms: lower temperatures, between 16 and 18 °C, which promote restorative sleep.
• Bathroom: maintained around 22 °C to avoid thermal shocks when exiting the shower or bath.
• Hallways and entries: can remain around 17 °C, passage areas where a higher temperature is less necessary.

This principle targets real comfort while avoiding energy waste in unoccupied or little-used spaces. It fits perfectly with modern installations provided by companies like Frisquet, Deltadore, or Climatic, which offer connected and intuitive control solutions.

Connected thermostats have become an essential ally of this personalization. Programmable remotely via an app, they allow precise temperature settings based on schedules or occupancy. This technology can significantly promote energy savings, estimated at around 15% according to various studies, without sacrificing comfort.

Area of the House	Recommended Temperature	Justification
Living Room & Dining Room	20 °C	Calm activities, gathering place
Bedrooms	16-18 °C	Promotes quality sleep
Bathroom	22 °C	Prevents thermal shocks and discomfort
Hallways & Entries	17 °C	Little occupied areas

In this adaptation process, relying on specialized and experienced brands like Viessmann or Saunier Duval ensures the reliability of installations. The professionalism of a skilled plumber like Paul Leclerc, with over 15 years of experience, can assist individuals in choosing, installing, and maintaining these modern systems, ensuring optimal execution quality.

References to Aids and Grants to Support Domestic Thermal Transition

In an economic context where reducing energy consumption becomes imperative for both household budgets and environmental reasons, several aid and grant schemes support investments in high-efficiency equipment.

In 2025, the site Prime Coup de Pouce Chauffage gathers numerous information on local aids, particularly in Essonne, where thermal renovation is subject to specific support. These aids particularly encourage the replacement of old systems with less energy-intensive solutions, even the gradual cessation of gas heating, as detailed on Prime Coup de Pouce Chauffage.

Initiatives involve:

• Replacing boilers with efficient models, incorporating condensing technologies or hybrid systems.
• Installing connected thermostats to improve heating regulation, with brands like Deltadore leading in this field.
• Renovating insulation, essential for maximizing system efficiency.
• Using renewable energies, such as solar heating or heat pumps with reduced electrical assistance.

Access to these aids is often conditioned by the realization of work by qualified professionals who guarantee a quality level compliant with requirements, reflecting the expertise of Paul Leclerc. He assists his clients in their administrative processes and offers solutions tailored to their budget and housing.

Type of Aid	Conditions	Benefits
Subsidies for energy renovation	Main residences, minimum performance	Significant cost reduction
Tax credit	Acquisition of eligible equipment	Interesting tax relief
Local aid (e.g. Essonne)	Work done by a qualified professional	Specific support and advice
Prime Coup de Pouce Chauffage	Boiler replacement	Financial incentives

Practical Tips to Fully Benefit from These Aids

• Check eligibility before starting work.
• Consult a recognized professional certified for the environment (RGE).
• Gather quotes and documents requested by the funding organization.
• Plan coherent scheduling of interventions to avoid double costs.
• Monitor compatibility of equipment, especially when installing connected thermostats.

With quality support and tailored solutions, moving away from the 19 °C framework becomes beneficial not only for comfort but also for the wallet.

Authentic Testimonials: Feedback on the Questioning of the 19 °C Standard

The renewal of heating habits is very real in households. Here are some testimonials from clients assisted in their thermal renovation by professionals like Paul Leclerc:

• Marie, 42, mother of a family: “After installing a Viessmann system with a connected thermostat, I’ve noticed a real improvement in comfort at 20 °C, without an explosion in the bill. My children are more comfortable at home, especially during remote work.”
• Jean, 68-year-old retiree: “I adhered to the 19 °C rule for a long time, thinking I was saving money. But in my bedroom, I was cold. I adjusted to 18 °C and everything is better. Sleep quality has improved, as has my health.”
• Sandrine, dynamic young adult: “With the Atlantic and Deltadore solutions my plumber recommended, I control my consumption while enjoying heating adapted to each room.”

These testimonials reflect a transition to smarter heating tailored to the real needs of occupants. By combining enhanced comfort and expenditure control, modern homes adopt a new energy philosophy.