Apartment F → E
65 m²Electric heating
65 m² 3-room electrically heated apartment, 380 kWh PE/m²/yr before reform. With the 1.9 coefficient: 314 kWh PE/m²/yr → moves from F to E.
My DPE in 2026
Check if your energy label changes with the current official electricity coefficient (dropped from 2.3 to 1.9 on January 1, 2026). Free and instant simulation.
2026 ReformOfficial ADEME dataFree to start
How does it work?
On January 1, 2026, the electricity-to-primary-energy conversion coefficient drops from 2.3 to 1.9. This reduces displayed primary energy consumption by ~17% for electrically heated homes, potentially changing the DPE energy label.
Key reform figures
2.3 → 1.9
New electricity conversion coefficient
~17%
Reduction in displayed primary energy
850,000
Homes exiting F/G classification
Jan 1, 2026
Effective date
How does it work?
1
Enter your data
Input your DPE number or enter consumption data manually.
2
Automatic calculation
The new 1.9 coefficient is applied to your electricity consumption.
3
Instant result
See your new energy label and the impact on your DPE.
Real-world reclassification examples
Here is how three typical homes see their energy label change with the new 1.9 coefficient.
House G → F
90 m²Electric heating
90 m² electrically heated house, 460 kWh PE/m²/yr before reform. With the 1.9 coefficient: 380 kWh PE/m²/yr → exits the "thermal sieve" status.
Studio E → D
30 m²Electric heating
30 m² electrically heated studio, 250 kWh PE/m²/yr before reform. With the 1.9 coefficient: 207 kWh PE/m²/yr → moves from E to D.
Estimates based on the official calculation (French decree of August 13, 2025). Your actual situation may vary depending on your DPE.
Who is affected?
Electric heating
All electrically heated homes benefit from the new coefficient. About 850,000 homes exit the "thermal sieve" classification.
Gas, oil, wood
Homes heated by gas, oil or wood are not impacted by this reform. Only the electricity conversion coefficient changes.
What the reform really changes — and what it does not
Moving the electricity conversion coefficient from 2.3 to 1.9, set by the decree of 13 August 2025, changes the calculation, not your home. That distinction has very concrete consequences.
The split is clear-cut
What changes
- Your stated primary-energy consumption, mechanically cut by around 17%
- Your energy label, if primary energy was what determined it
- Your energy-sieve status, and therefore your right to let the property
What does not change
- Your actual final-energy consumption — the one you are billed for
- Your bills, at a constant price per kWh
- Your thermal comfort, insulation and heating system
- Your climate (GHG) label, which follows a separate scale
The point almost everyone misses
A DPE label always takes the WORSE of two scores: the primary-energy one and the greenhouse-gas one. That rule decides who gains something from the reform and who gains nothing.
Electric heating: the French mix is low-carbon, so your GHG score is generally good. It is primary energy that caps your label — and that is exactly what the reform improves. You are the winning case.
Gas, oil or wood heating: your label is usually capped by GHG, which the reform does not touch. You may see your primary-energy figure drop slightly without your letter moving at all. That is not a bug in the simulator.
A better label is not a better home
There is a reason to check your new label rather than simply welcome it. In our reliability barometer, a flattering label is no guarantee of rigour: B-rated certificates most often carry a major inconsistency (27.9%), ahead of G-rated ones (22.2%) and A-rated ones (19.7%). The full ranking follows no logic of performance — F-rated certificates come last at 4.3%, while G-rated ones, just as energy-hungry, are five times more affected.
Direct electric heating is also the case our data isolates most clearly. Across 439,708 observable buildings of 5 units or more, 1,097 — 0.25% — show a configuration consistent with over-rating: a pre-2000 building, at least five dwellings rated A or B, and direct electric convector heating. That is physically unlikely without heavy renovation. The first alternative explanation, worth keeping in mind, is precisely a genuine collective renovation — external insulation, connection to a district heating network — that was never reflected in the certificates. Either way, a check settles it.
These figures cover the sub-sample our data lets us observe, never the national stock. An atypical signature is a signal to check, not a verdict.
The mistakes that skew the simulation
- 1
Entering final energy instead of primary energy
In manual mode, the field expects primary-energy consumption — the large figure on the energy label, covering 5 uses. The DPE also shows a final-energy figure: for an all-electric home surveyed before 2026, it is roughly 2.3 times lower (1.9 times since).
What it changes: The simulator then places the home several letters too high: entering 180 kWh of final energy instead of 415 in primary energy displays a C instead of an F. The percentage reduction itself stays the same — it is not the reduction that is wrong, it is the starting point, in the most flattering direction.
- 2
Declaring "electricity" for mixed heating
Choosing "Electricity" in manual mode makes the calculation assume all consumption is electric. Yet many homes combine electric heating with gas, oil or wood for hot water or as a backup.
What it changes: The label gain shown is overstated. The "by DPE number" mode solves this: the simulator retrieves your actual consumption and applies the reduction only to the electric share.
- 3
Forgetting that the climate label is unknown
A DPE label always takes the worse of two grades, energy and climate. In manual mode the simulator does not know your climate grade: it can only compute the energy side.
What it changes: For a home whose climate grade is what caps the label, the manual result is too optimistic. Here too, the "by DPE number" mode retrieves the climate grade and lets it apply.
- 4
Simulating a certificate already issued in 2026
Certificates issued from 1 January 2026 already apply the 1.9 coefficient. Applying the reform to them a second time counts the reduction twice.
What it changes: The label announced can come out one class better than the real one. Check the issue date at the top of the certificate: if it is after 31 December 2025, the label shown is already the right one — there is nothing to simulate.
- 5
Not checking the starting certificate
The simulator takes your certificate’s figures as they are: it converts them, it does not check them. If the starting certificate contains an error, the projection reproduces it exactly.
What it changes: Across the 689,279 certificates our data lets us observe, 11.1% carry at least one major inconsistency. That rate aggregates eight families of checks and does not include the primary-to-final-energy ratio, counted separately: 5.3% of certificates show an inconsistency there, all severities combined — precisely the ratio the reform changes.
- 6
Mistaking the simulation for the official document
The result shown here is a projection: it is not legally binding and does not replace your certificate. The document that officially carries the new label is the free attestation issued by ADEME’s DPE-Audit observatory, with no new visit from an assessor.
What it changes: A screenshot of the simulator carries no weight in a listing, a lease or a sale agreement. It is also what makes some owners receptive to a paid "updated DPE", when the official attestation costs nothing.
What you actually need to do
Nothing mandatory, and certainly not a new survey. Your current certificate stays valid for its full ten years. Certificates issued since 1 January 2026 already apply the new coefficient. For an earlier one, ADEME provides a free attestation applying the new calculation, with no new visit from an assessor — that is the document to ask for before paying anyone offering you an "updated" DPE.
Sources and method
Coefficient and timetable: decree of 13 August 2025, in force from 1 January 2026. Inconsistency rates by label: our barometer across 689,279 ADEME certificates, post-stratified by department and vintage. Atypical signatures: national certificate database (category A, 3CL-2021 method), flats grouped by address, buildings of at least 5 units. the reliability barometer · the verification tool
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ADEME ObservatoryFrequently asked questions
Why does the coefficient change?
The electricity final-to-primary energy conversion coefficient dropped from 2.3 to 1.9 on January 1, 2026 — that's the current official value. This reflects France's increasingly decarbonized electricity grid (nuclear + renewables). The 2.3 coefficient, set in 2006, no longer reflected reality.
Does my existing DPE remain valid?
Yes. DPEs issued before 2026 remain valid for their full 10-year period. You can get a free updated attestation on the ADEME DPE Observatory website without a new on-site visit.
Do I need a new DPE?
No. DPEs issued from January 1, 2026 will automatically use the new coefficient. For existing DPEs, a free attestation is available on the ADEME Observatory.
Does my home exit "thermal sieve" status?
If your home is electrically heated and rated F or G, it may move to E or better with the new coefficient. Use our simulator above to check.
Is the reduction always 17%?
No. 17.4% is the maximum, reached only when all of the home's consumption is electric. The calculation removes 0.4 kWh of primary energy per kWh of electricity consumed: a home heated by electricity but with gas hot water falls less, and a home with no electricity does not fall at all. In "DPE number" mode, the simulator uses the actual breakdown from your certificate.
My consumption falls but my label does not move — is that normal?
Yes, it happens often. Each letter covers a consumption band: an all-electric home at 415 kWh PE/m²/year drops to 343, which leaves it in F, a class that runs up to 420. The rule is simple: with a maximum reduction of 17.4%, you only change letter if your current consumption exceeds the bottom of your class by at most 21% — for an F, up to about 400 kWh PE/m²/year. Above that, the letter does not move. There is another case: if it is your climate label that caps the grade, the reform does not touch it.
My home moves from G to F — can I sign a new lease?
Yes, until 1 January 2028 (state of the law as at 28 July 2026; check again before any decision). In mainland France, G-rated homes have been banned from new lettings since 1 January 2025, F-rated ones will follow on 1 January 2028 and E-rated ones on 1 January 2034 — Climate and Resilience Act no. 2021-1104 of 22 August 2021, article 160. Overseas the timetable is shifted: G in 2028, F in 2031. Ongoing leases are not broken: only new lettings and renewals are concerned. And it is the label on the certificate currently in force that counts, not a simulation.
Does a better label push up the sale price?
Nothing guarantees it. Across the house sales our data lets us observe, the median price per m² of F-rated houses is 15.9% below that of D-rated ones, against 6.9% for E-rated ones. This is not a like-for-like comparison: those gaps are corrected neither for fine-grained location nor for the age of the building. It is an observed gap between labels on past sales, not a measured effect of the reform — the home itself has not changed, and buyers still read final-energy consumption and bills.
Why does the simulator ask for the floor area?
Because below 40 m², the label thresholds are raised: that is the small-surface correction of the decree of 25 March 2024, in force since 1 July 2024. Fixed consumption — hot water, base heating — weighs proportionally more in a small home. The uplift depends on both the area and the class, and it is sometimes enough to change the letter. Enter the habitable area shown on the DPE, not the Carrez area nor the gross floor area.
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