Press ESC to close

2 Min Read

While the heat wave is hitting France hard, the heat wave reminds us how important the thermal insulation of our homes is. In this regard, Hello Wattthe energy advice platform for individuals, carried out a study taken over by BFMTV this Monday, June 20, on the metropolises which have the most thermal strainers.

The study, which is based on data provided by the Environment and Energy Management Agency and the 2017 INSEE census, shows that the cities with the fewest thermal sieves are mainly located in the south of the country. Conversely, Île-de-France is the region with the highest number of poorly insulated homes.


The ranking is dominated by Perpignan (4.2% of dwellings classified F or G), Nîmes (6.6%) and Angers (6.6%). According to Hello Watt, the good insulation of southern cities can be explained above all by the type of construction materials used: “One of the reasons which may explain this phenomenon lies in the materials used for the construction of housing, which vary or have varied according to the regions. In Provence, for example, many houses are made of stone, which makes it possible to store the heat during the day and to diffuse it gradually in the accommodation when the temperature drops”. In addition, the low share of old housing can also explain these good results.

The Paris region at the back of the pack

The cities of northern France appear to be bad students, in particular the Paris region which has seven municipalities in the ranking of the least well isolated cities. The situation is particularly bad in Paris (24%), Saint-Denis (22.3%) and Argenteuil (21.8%) where more than a fifth of housing is considered to be thermal sieves. According to the study, this poor ranking is explained in particular by the proportion of housing built before 1970 as well as a price per m2 which “may deter some households from reducing their living space with interior insulation”.

The “rich” cities are not necessarily the best isolated. The Hello Watt study thus shows that 58% of thermal colanders are occupied by intermediate or wealthy households.


At departmental level, the ranking is dominated by the regions of south-west France, with Gironde in the lead (5.4%). Conversely, it is in the Alpine departments that we find the most thermal colanders. The Hautes-Alpes account for 30.2%, Savoie 28% and Haute-Savoie 26%. According to Hello Watt, this poor thermal performance is essentially due to “the cold and rough climate which requires a significant need for heating, and increases consumption per m2”.

Since the vote on the Climate Law last summer, landlords know that the least energy-efficient housing will soon be banned from renting. In detail, this ban will apply from 2023 to the 90,000 homes consuming more than 450 kWh of final energy per year and per square meter. Then, the ban will hit dwellings classified with the letter “G” on the energy performance diagnosis (DPE) in 2025, those classified “F” in 2028, and dwellings classified “E” from 2034. Just for housing classified F and G, this concerns approximately 1.7 million rentals!

Show Comments

Share Article:

Exit mobile version