Energy audit in case of sale of a property called “thermal colander”

Verified 01 January 2025 - Directorate for Legal and Administrative Information (Prime Minister)

You are going to sell your property and want to know if you need to provide an energy audit to the buyer? We explain when you need to provide the audit and what it contains.

Energy auditing is a real estate diagnostic that consists of carrying out a energy and environmental performance stocktaking buildings.

It aims to to make the future purchaser aware the environmental and energy issues of the building (dwelling, building) it plans to purchase.

Moreover, he directs it by making proposals of works to improve thermal comfort and air quality and achieve a high performance renovation of the building.

The obligation to carry out an energy audit relates to buildings put up for sale (single-family houses, buildings composed of several dwellings of which you are the sole owner) heat strainer, i.e. buildings Class F or G by the DPE.

Since 1er january 2025However, this also applies to buildings class E.

From 1er january 2034, this obligation concern the buildings D-class.

The buildings concerned by the obligation to carry out the energy audit are those whose promise of sale or the bill of sale has been signed since 1er april 2023.

FYI  

In the overseas departments and regions, the obligation to carry out an audit for buildings Class F or G applies from 1er july 2024. From 1er january 2028, this obligation also applies to buildings class E.

The audit must be carried out by a professional (in particular, businesses of architects and architects registered with the order and having undergone training, recognized professional guaranteeing the environment) certain qualifications.

FYI  

The selected auditor cannot sub-contract the audit.

To perform the audit, the auditor must perform at least 1 visit of the building in your presence or that of a third person whom you have authorized.

To facilitate this audit, you must provide the auditor with the following documents:

  • Summary of your DPE
  • Your invoices for work already completed
  • If you have them, the different technical real estate diagnostics (e.g. electricity, gas).

Directories are available:

Find a Certified Real Estate Diagnoser

Search for a company with the quality "Recognized Guarantor of the Environment"

The audit shall include the following information:

  • Estimation of energy performance before work
  • Proposals for work in 1 or more stages
  • Energy performance after work
  • Cost of works and aid available
  • Condition of ventilation or ventilation of the building after work.

Estimation of energy performance before work

The audit shall include the following:

  • Estimation of energy performance before work according to the calculation method used to perform the EPD. This estimate can be based on the data collected for the last EPD of the building.
  • Diagram showing the distribution of heat losses
  • Information on existing control devices (measuring, regulating and controlling devices controlling the building equipment).

Proposals for work

The audit must contain 2 minimum work proposals for achieving a successful renovation.

These proposals must comply with the following conditions:

  • They must be compatible with the technical, architectural and heritage characteristics laid down in the Heritage Code (for example, in the case of a listed building)
  • They must not be disproportionate to the value of the property (this is the case when the cost of the work exceeds 50% the value of the property).

Each proposal must include a work path in 1 or more steps consistent with each other. They must make it possible to ensure satisfactory treatment of interfaces and interactions, in particular thermal bridges and air tightness, and the attainment of a satisfactory level of hygrothermal comfort.

FYI  

The technical solutions defined in the work proposals must be compatible with the state of the building, in particular as regards the materials of the opaque walls (walls, low floor and roof).

1re proposal

It must provide for a step-by-step workflow to achieve a successful renovation.

This work path includes in particular the study of six work stations :

  • Insulation of walls
  • Insulation of low floors
  • Roof insulation
  • Replacement of exterior carpentry
  • Replacement of ventilation
  • Replacement of heating and domestic hot water production and associated interfaces.

This work path must comply with the following conditions: 

  • The 1re stage of works must make it possible to achieve a gain of at least 2 energy classes and to carry out the treatment of 2 insulation stations
  • The final step shall achieve a level of performance at least equal to that of performance class B
2of proposal

It must provide for a 1-step workflow to achieve a successful renovation.

This work path includes in particular the study of six work stations :

  • Insulation of walls
  • Insulation of low floors
  • Roof insulation
  • Replacement of exterior carpentry
  • Replacement of ventilation
  • Replacement of heating and domestic hot water production and associated interfaces.

Energy performance after work

The audit shall specify for each stage of the work path the following information: 

  • Annual energy consumption primary and final of the building after work related to its surface after work expressed respectively in kWhEP/m²/year and kWhEF/m²/year for each of the energy uses (heating, cooling, domestic hot water, lighting and auxiliaries) 
  • Total annual energy consumption primary and final of the building after work related to its surface after work expressed respectively in kWhEP/m²/year and kWhEF/m²/year for all energy uses (heating, cooling, domestic hot water, lighting and auxiliaries). These consumptions are estimated with and without deduction of the production of self-consumed photovoltaic energy
  • Greenhouse gas emissions of the building after work for all energy uses (heating, cooling, domestic hot water, lighting and auxiliaries) related to the surface after work expressed in kgCO2eq/m² SHAB/year
  • Energy Performance Rating building after work, taking into account the total annual primary energy consumption for all energy uses (heating, cooling, domestic hot water, lighting and auxiliaries)
  • Greenhouse gas classification of the building after work within the meaning of the EAD
  • Estimated energy savings in primary and final energy, and avoided greenhouse gas emissions (in absolute terms, then in relative terms to the initial state before work)
  • Estimation of the theoretical impact of the work proposed on annual energy charges, in the form of a cost-saving range.

Cost of works and aid available

The audit shall include the following information:

  • Estimated cost of energy performance improvement work and other work necessarily related to the completion of such improvement work
  • Main financial support available for this work.

The auditor must ensure that the work packages are selected in a manner consistent with the expected energy savings and the value of the property.

Ventilation or ventilation conditions of the building prior to work

The audit should mention recommended work on opaque or glazed walls facing the exterior of buildings.

Ventilation and heating installations may be accompanied by one of the following measures:

  • Additional work to ensure sufficient but controlled renewal of air
  • Recommendations on the management and maintenance of the ventilation system to ensure satisfactory air renewal conditions. When the air renewal is insufficient or uncontrolled, the work to remedy it is proposed as early as 1re stage of the work path.

Where the technical, architectural, heritage or disproportionate cost of the works prevent class B from being attained, an upgraded work path shall be provided.

This landscaped course integrates the study of the six work stations :

  • Insulation of walls
  • Insulation of low floors
  • Roof insulation
  • Replacement of exterior carpentry
  • Replacement of ventilation
  • Replacement of heating and domestic hot water production and associated interfaces.

It allows a minimum of class C, D or E for buildings classified respectively as E, F or G before work.

The six work stations are considered to be treated if the auditor certifies that these stations have been raised to a high level of performance using the best available techniques compatible with the building's characteristics.

In case of disproportionate cost, the calculation of the cost of the works takes into account what is necessary to bring the building to the level of the stage studied.

The audit shall give rise to a summary report and to a summary standardized.

Summary Report

The audit shall give rise to a summary report drawn up in PDF format, including in particular the following information and documents:

  • State of the building. The auditor may take stock of the building's situation as indicated in the EPD, after having checked beforehand during his visit that the elements of the standardized summary of this diagnosis are those actually implemented in the building and having corrected them if necessary
  • Summary of all audit content items
  • Annex explaining the different technical concepts
  • Reference to the structures responsible for providing information, advice and support for energy renovation
  • Justification of the technical, architectural, heritage or cost characteristics of the works that allow a derogation from the audit content
  • Name and version of audit software used.

The summary report must be sent to you within one month of the date of the visit of the building, in a format paper and informatics.

Standardized Summary

The audit shall also result in a standardized summary at XML format containing all the data provided by the auditor and those calculated for carrying out the audit, including the following:

  • General, including building administrative data
  • Characteristics of the building envelope (surfaces, orientation, thermal characteristics, ...)
  • Characteristics of technical systems (types of energy, generator, emitter, ventilation, presence of boiler-related ratio, etc.)
  • Indicators of the performance of the building before work (primary and final energy consumption, greenhouse gas emissions, annual energy costs, etc.)
  • Recommendations for improvement and indicators of the performance of the building after work (technical description of the work, primary and final energy consumption, ...)
  • Economic and financial analysis of the recommendations for improvement (estimation of the cost of the work to improve the energy performance of the building and of the other work needed, financial assistance available, annual energy costs after work, etc.).

Auditing is valid for 5 years.

The Listener keeps track of all the audits it carries out in the form of standardized computer files.

The auditor shall keep at the disposal of successive owners the audits he carries out during their period of validity.

The cost of the audit is not regulated, the the price may therefore vary from one professional to another.

FYI  

The cost of the audit can be supported by the prime Boost efficient renovation of a detached house or MaPrimeRenovate' under certain conditions.

Who can help me?

Find who can answer your questions in your region

  • Specialist advisors on housing renovation works (France Rénov')

    Allows you to be accompanied for free in its renovation work by specialized advisors of France Rénov'

    By telephone

    0 808 800 700

    Open from Monday to Friday from 9am to 6pm. You must have your last tax notice.

    Free service + cost of a call