Collective vs individual EPC: what condominium owners need to know

You have just had an EPC carried out on your flat in a condominium. It shows class D. Your neighbour on the same landing, same floor, same orientation, same floor area, had theirs done six months later: class F. The building has also just had a collective EPC produced, which shows class E for the entire building.

Three EPCs. Three different classes. Which one counts for letting purposes? Which one engages the managing agent's liability? Which one requires you to carry out works? Which one is legally binding on the buyer in the event of a sale?

The coexistence of collective and individual EPCs in French law is a persistent source of confusion — even among property professionals. Both documents share the same 3CL calculation method, but cover different analytical perimeters and produce legal effects that do not substitute for one another. Understanding how they interact has become essential for any landlord or seller in a condominium.

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Are You Affected? Your Situation by Type of Condominium

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What Each EPC Measures — and Why They Diverge

The individual EPC: the unit as the analytical perimeter

The individual EPC for a flat in a condominium is produced using the 3CL-DPE 2021 method (Order of 31 March 2021) applied to the private unit alone. The diagnostician analyses the thermal characteristics of the unit's walls (external walls, floors, ceilings, windows), the heating and hot water system assigned to the unit, and the ventilation.

The specific difficulty in condominiums is that certain crucial parameters are not fully controlled at the unit level:

• Collective heating (boiler or district heating serving the building) is modelled from the capacity and efficiency of the collective installation, apportioned between units by their share — but the diagnostician only has access to general data communicated by the managing agent, whose reliability varies
• Party wall insulation (walls between flats, floors between storeys) is difficult to verify physically — the diagnostician often uses default values from the regulatory database
• Thermal bridges at the junction between private and common parts (slab/wall connections, continuous balconies) are not always identifiable without inspecting roof spaces or cellars

These limitations mean that two identical units in the same building can receive different EPC classes depending on the data entered by each diagnostician — a phenomenon that the 3CL 2021 reform reduced but did not eliminate.

The collective EPC: the building as an energy system

The collective EPC, introduced by the Climate and Resilience Act (Law no. 2021-1104 of 22 August 2021, article 158), is produced for the entire building by a single diagnostician who has full access to common parts, collective equipment (boiler, distribution network, heat exchanger), and the building's energy consumption records.

It uses the same 3CL method as the individual EPC, but with a much broader analytical perimeter: the diagnostician can directly gather the actual characteristics of the collective boiler, the measured efficiency of the distribution network, and the real condition of the common parts' envelope. The building's energy consumption records (gas or heating oil bills, meter readings) serve as consistency data to verify that the 3CL calculation results match measured reality — and to adjust input parameters if a significant discrepancy appears.

This better quality of input data explains why the collective EPC is generally more accurate than the sum of individual EPCs produced separately, where each diagnostician works with fragmentary information communicated by the managing agent.

The collective EPC also produces a prioritised works plan identifying priority interventions on common parts — it thus serves as the reference document for feeding the condominium's Multi-Year Works Plan (PPT — Plan Pluriannuel de Travaux). On what the PPT covers — and does not cover — for your unit, see our guide condominium and EPC: when the renovation plan isn't enough.

Why the two classes often diverge

The divergence between collective and individual EPCs is systemic, not accidental. Several factors explain it:

Factor #1 — Data quality on collective heating. In a building with collective gas heating, the individual EPC models the boiler from data communicated by the managing agent — sometimes imprecise or outdated. The collective EPC uses manufacturer data and actual performance readings. If the boiler is old and its actual efficiency degraded, the collective EPC detects this where individual EPCs may have underestimated it.

Factor #2 — Mid-floor flats are favoured in individual EPCs. A unit on the 3rd floor of 5 benefits from the buffer effect of the floors above and below — its heat losses through upper and lower floors are low. The individual EPC values this advantage. The collective EPC integrates top-floor flats (high roof losses) and ground-floor flats (floor losses) into the overall performance — which pulls the collective class down compared to individual EPCs of mid-floor units.

Factor #3 — Orientation and exposure. A well-oriented dual-aspect flat achieves a better individual EPC than the building's collective EPC, which integrates all orientations.

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Distinct Legal Effects: What Each One Triggers

The individual EPC: the document that binds the landlord and the seller

It is the individual EPC — and it alone — that determines letting and sale obligations at the unit level.

For letting:

The ban on letting G-rated properties (since 1 January 2025) and F-rated properties (from 1 January 2028) applies to the individual EPC class of the unit, not the building's collective class. A flat rated F individually in a building collectively rated D is subject to the 2028 letting ban, despite the good collective rating. Conversely, a unit rated D individually in a building collectively rated F is not subject to the letting ban — the individual class prevails.

The rent freeze (Decree no. 2022-1143 of 24 August 2022) follows the same logic: it applies to properties whose individual EPC shows class F or G.

For sale:

The individual EPC must be provided in the technical diagnostics file (DDT) appended to the preliminary and final contracts of sale (CCH article L.271-4). This is the document that has been legally binding on the buyer since 1 July 2021. If the individual EPC is inaccurate, it is the diagnostician's liability — and potentially the seller's — that is engaged.

The collective EPC: the document that binds the condominium

The collective EPC is a document of asset governance for the condominium — it is not appended to the sale contracts of individual units and is not legally binding on the buyer of an individual unit.

Its legal effects are different:

• It is the documentary basis for the Multi-Year Works Plan (PPT) that condominiums over 15 years old must now establish (Climate and Resilience Act, article 90 — CCH article L.731-1)
• It is transmitted to the buyer of a unit for information purposes — it must be included in the documents provided by the managing agent at the time of sale (CCH articles L.721-1 et seq.), but without direct enforceability regarding the unit sold
• It serves as the reference document for MaPrimeRénov' Copropriété applications and collective works financing files

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Can I Use the Collective EPC Instead of the Individual EPC?

The answer is no — without exception in condominiums.

Since 1 July 2021, each unit sold or let in a condominium must have its own individual EPC produced using the 3CL 2021 method. The collective EPC cannot substitute for the individual EPC to satisfy the legal diagnostic obligation at sale or letting — even if the building has just had a complete and recent collective EPC produced.

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Simulation: The Collective/Individual EPC Class Gap and Its Consequences

Profile: T3 flat, 4th floor of 5, 62 m², Haussmann-era building in Paris 11th arrondissement, built in 1890, collective gas heating. Building's collective EPC: class E (295 kWh PE/m²/year). Unit's individual EPC: class F (345 kWh PE/m²/year) — due to insufficient insulation of the external street-facing walls and a degraded actual efficiency of the collective boiler, identified in the collective EPC but underestimated in the individual EPC for lack of precise data communicated by the managing agent.

The property is subject to the 2028 letting ban on the basis of its individual EPC (class F) — despite a collective EPC of class E that might suggest the situation is under control. If the owner does not carry out works on their unit by 2028, they will no longer be able to let it. The estimated discount on the unit's sale value is 7 to 10% based on notarial data for an F-rated flat in Paris.

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What Owners Should Do According to Their Situation

You are a landlord with a unit rated F or G individually

1. Check the individual class, not just the collective class. If your individual EPC is over 10 years old or was produced before July 2021 using the old method, have it redone: it can no longer be used legally since 1 January 2025 (for 2018-2021 EPCs) and the classes may have changed significantly with the 3CL method.
2. Consult the collective EPC to identify common parts works that would improve your individual class — roof insulation, collective boiler replacement, façade wall insulation. These works, decided at the AGM, can move your unit from F to D without any private works on your side.
3. Simulate the class improvement after private works if collective works are insufficient or too far off in the PPT — internal wall insulation for external-facing walls, window replacement, individual heating regulator.

You are a seller

1. Your individual EPC must be valid (less than 10 years old, 3CL 2021 method if produced after July 2021) and included in the DDT.
2. If the collective EPC reveals significant works voted in the PPT — façade renovation with insulation, boiler replacement — anticipate their impact in the price negotiation: the buyer will be informed of the collective EPC and associated provisional fund calls.
3. If your unit is rated D individually in a building collectively rated F, highlight this gap explicitly: your unit is spared the letting constraints affecting your neighbours, and will benefit from revaluation when future collective works are carried out.

You are a buyer

1. Insist on the individual EPC of the unit in the DDT — this is your reference document for future obligations.
2. Also request the building's collective EPC (transmitted by the managing agent): it reveals the actual condition of the envelope and collective equipment, works voted or planned in the PPT, and anticipates future fund calls to which you will be subject as a co-owner.
3. A unit rated D in a building collectively rated F should alert you: if significant collective works (façade insulation, boiler replacement) are planned, your unit will benefit from revaluation — but you will also be called upon to finance these works in proportion to your share.

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Common Mistakes by Condominium Owners

Mistake #1 — Believing that a good collective EPC protects the unit. This is the most common and costly mistake. An owner who sees the collective EPC of their building displayed as E concludes that their flat is not affected by the letting bans. If their individual EPC is F, they are subject to the 2028 letting ban — regardless of the collective rating.

Mistake #2 — Not redoing the individual EPC after significant collective works. A collective boiler replacement, roof insulation voted at the AGM, façade renovation with external insulation — all these works change the thermal characteristics of the unit and can shift its individual EPC class. Failing to update the individual EPC after significant collective works means missing a revaluation opportunity for the unit.

Mistake #3 — Confusing the collective EPC obligation with exemption from individual EPC. The establishment of the collective EPC by the managing agent does not exempt unit owners from their individual EPC obligation at sale and letting. The two obligations coexist and are independent.

Mistake #4 — Ignoring the collective EPC when buying. The collective EPC is rarely read carefully by buyers, yet it is the most comprehensive document on the building's actual condition. It contains the state of collective equipment, works scenarios with their estimated class impact, and provisional fund calls associated with the PPT.

Mistake #5 — Having the individual EPC produced without sharing the collective EPC data. The collective EPC contains data on the collective boiler, distribution network, and common parts insulation that is directly reusable in the individual EPC calculation. Sharing this data with the diagnostician before the visit improves the accuracy of the individual EPC — and prevents unfavourable default values from being used for lack of information, which can unnecessarily penalise the unit's class.