By Garen Ajderhanyan · 19 July 2026 · 7 min read
In brief
The EPC classifies a dwelling from A to G, based on its energy consumption and greenhouse gas emissions; it is compulsory for selling as well as letting. Classes F and G, known as "energy sieves", are subject to progressive letting restrictions. Older buildings in Nice, often well built but fitted with dated joinery and heating, receive poor ratings that targeted works can improve. According to the Étude Maison Masséna (H1 2026), each letter gained on the EPC is worth approximately 1.5% on the price.
What does the EPC measure?
The Energy Performance Certificate, the EPC, assigns a dwelling a class from A to G, on two counts: energy consumption and greenhouse gas emissions. The letter displayed reflects the worse of the two. It is compulsory for selling as well as letting, and its result must appear from the listing.
From La Gazette, I see many diagnostics of flats in Nice pass by. Classes F and G, which common usage has called "energy sieves", are subject to progressive letting restrictions. The precise timetable evolves; for current deadlines, I prefer to refer to ADEME and Service-public.fr rather than cite dates from memory.
Why is an older building often less well rated?
A Belle Époque building has qualities that the EPC does not measure: ceiling heights, thick walls, thermal inertia that retains coolness in summer. What the method assesses are the fabric and its equipment, and that is where the older property fails. Original single-glazed joinery, electric heating installed forty years ago, absence of considered ventilation: so many points that pull the rating down.
A qualification specific to Nice must be added. The climate of the Côte d'Azur softens actual consumption, but the EPC calculation is conventional: it rates the building and its systems, not the mildness of winter. A seafront flat can therefore live comfortably and display an E.
Does the EPC change the value of a property?
Yes, and in a manner now measurable. In the study published by Maison Masséna in the first half of 2026 on the Nice market, each letter gained on the EPC is worth approximately 1.5% on the price. On a flat at one million euros, moving from E to C therefore represents in the order of thirty thousand euros, without counting the difference in time to sell.
The effect also plays at letting: a poorly classified dwelling lets less easily, or not at all eventually for classes subject to restrictions. For the landlord of an older flat, the rating is no longer an administrative detail; it forms part of the balance sheet.
Can the rating of a Belle Époque flat be improved?
Often, yes, and without disfiguring the building. The three usual levers are windows, heating and ventilation. Replacing single-glazed joinery with double glazing respectful of the original designs, modernising an old heating system, installing suitable ventilation: these targeted works sometimes suffice to gain one letter, occasionally two.
Two precautions. In co-ownership, part of the works concerns common parts and is decided at general meeting. And in certain protected perimeters of central Nice, façade modifications require authorisations. Before committing to anything, an energy audit provides the order of priorities; public assistance in force is described on the ADEME and Service-public.fr sites.
Frequently asked questions
- Is the EPC compulsory for selling or letting in Nice?
- Yes. The EPC is compulsory for any sale and any letting of a dwelling in France, and its result must appear in the listing. Conditions of validity and particular cases are detailed on Service-public.fr.
- What is called an "energy sieve"?
- A dwelling classified F or G on the EPC. These classes are subject to progressive letting restrictions. The exact timetable being liable to evolve, it must be checked with ADEME or Service-public.fr.
- Is a Belle Époque flat necessarily poorly classified?
- No, but it often starts with a handicap: original joinery, dated heating, absent ventilation. Thick walls play in its favour, without on their own compensating for old equipment. Each diagnostic remains specific to the dwelling.
- How much is an EPC letter worth on the price of a property?
- According to the Étude Maison Masséna published in the first half of 2026 on the Nice market, each letter gained on the EPC is worth approximately 1.5% on the price. That is the only figure I cite here; it is dated and sourced.
- Which works most improve the rating of an older dwelling?
- Windows, heating and ventilation are the three usual levers. An energy audit allows prioritisation; in co-ownership, interventions on common parts go through the general meeting.
References
Districts
The author
Garen AjderhanyanEditor of La Gazette de la Promenade
Editor of La Gazette de la Promenade. He writes on Riviera property and the art of living, from Nice.