Under the Climate and Resilience Law, the most energy-intensive housing, below the energy indecency threshold, can no longer be rented from January 1, 2023. In mainland France, all energy class G housing will follow. in 2025, then F in 2028 and E in 2034.
According to the study, 45% of main residences in Ile-de-France fell into one of these three energy classes in 2018. A figure that rises to 55% for private rental housing, and 48% for owner-occupied housing.
Social housing, more centrally managed, is the best student with only 29% of labels E, F or G.
The study was carried out with the old energy labels, based on user bills. The method of establishing diagnoses was reformed in mid-2021 to take greater account of the objective characteristics of buildings, and to integrate greenhouse gas emissions.
But "the orders of magnitude are the right ones, and if they need to be adjusted, it is rather upwards", assures Martin Omhovère, director of the Habitat department at the Paris Region Institute.
Private housing faces particular difficulties: they are often in condominiums, where undertaking renovation work can be very tedious, and are more often occupied by low-income households, who do not have the means to finance a renovation or to absorb the increase in rent that it would entail.
"Whether in the owned stock or in the private rental stock, there is systematically a gap between the standard of living of the households which occupy the energy-intensive stock and the others", details Franziska Barnhusen, project manager at the Institute. Paris Region. "It shows that the people who occupy these thermal colanders are more vulnerable," she said.
The renovation work carried out so far has been ineffective and poorly targeted at the dwellings that need it most, the authors also note.
In question, the dysfunctions of the condominiums, but also the fact that the owners of individual houses rarely put energy gains at the heart of their work projects.