Energy renovations in France can cost more than €1,000 per metre square, a new study has found, with owners required to ensure their properties have at least an E energy rating before renting.
Since January 1, 2025, rental properties have been required to have at least an F rating on the DPE (diagnostic de performance énergétique) for new contracts. This means that owners whose property has a G rating or lower must undertake renovation work to bring the rating up to this.
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Renovations must be comprehensive, however, as landlords with the lowest level rating will probably want to improve their properties by more than one level (e.g. by more than just one increase from G to F).
This is because properties with an F rating will be banned from rental from January 1, 2028, and those rated E will be banned from 2034.
Similarly, government funding scheme MaPrimeRénov’ requires properties to rise at least two levels on the DPE to qualify for the aid (e.g. from G to E or above), and for two major changes (e.g. new insulation and a new ventilation system). This was relaxed to one change for the period May 15 to December 31, 2024, but it has now reverted to two.
The cost of renovations can be high; up to €1,000-1,500 per square metre for an apartment, depending on the work that is needed.
Read more: What is France Rénov’ aid scheme – can I use it to renovate my house?
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Read more: Is France’s DPE property energy rating based on actual bills?
New study on renovation costs
A new study by online lettings agency Imodirect, reported by specialist website Journal de l’Agence, has found that at least 2.3 major changes are required to enable properties to gain two levels on the DPE.
The study comes from data collected by the agency across 120 apartments with an average surface area of 26 m2. It found:
“When it comes to renovating rental properties, landlords are not looking to renovate their homes overall, but to ensure that they are legal and can be rented out on a long-term basis while guaranteeing a certain level of comfort for tenants,” said Arnaud Hacquart, founding president of Imodirect, to Journal de l’Agence.
To carry out the required work, it costs owners an average of €9,940 including VAT, with an average amount of aid of €3,157 including VAT, the study found.
It added that the average cost of a single project (e.g. insulation) is €4,121 including VAT without assistance, dropping to €2,812 including VAT when MaPrimeRénov' and CEE assistance (certificats d’économies d’énergie, energy saving certificates) funding is granted.
These figures tally with a study by the Observatoire National de la Rénovation Énergétique (ONRE), published in May 2021, highlighted by renovation and aid experts Hellio.
This study found that the average budget spent by households that carried out energy renovation work between 2016 and 2019 was €9,100 (including materials and labour).
However, more than a third of households that carried out renovation work in 2019 had completed another project at least once in the previous two years, bringing the average expenditure for these households to €18,600.
‘Focus on insulation and ventilation first’
François Moreaux, Nantes manager of specialist works agency Illico Travaux, recommends that owners focus on insulation and ventilation as the major priorities first.
“Insulation work is the most important,” he told Capital. “Start by insulating the attic and the roof. Because warm air rises, it will escape through the roof if the property is poorly insulated.”
He then recommends modernising the ventilation system, with a particular focus on natural ventilation, such as increasing the number of windows. Adding double- or triple-glazing can also improve the DPE rating significantly, as many low-rated properties “often have single glazed windows", he said.
Only then should any further changes be considered, such as improving the heating system, he added.
Yet, he advised that in addition, the refurbishment of the bathroom and kitchen and the upgrading of the electricity system to meet current standards - which is often needed - “will cost €50,000 to €60,000 for a 100-square-metre house, and €1,000 to €1,500 per square metre for an apartment”, he said.
Similarly, the Imodirect survey found that the most common changes made to properties for the purposes of improving the DPE rating are:
The installation of thermostatic taps (59%)
Double-glazed windows (53%)
Interior insulation (47%).
Attic insulation is only done in 6% of cases, however, it said.
The study also found that these changes are not always the most expensive; thermostatic taps account for 15% of the budget, with double-glazed windows and internal insulation accounting for 38% and 25% respectively.
Common renovation costs
A Hellio report, using figures from sources including the ONRE and ecological transition agency ADEME, estimated common costs at:
Roofing and insulation
Roofing work: Major price variations, but 10% of roofing projects cost over €15,500, with the median being €2,600
Interior insulation: €18-112 per square metre, with a median price of €55
External insulation: €43-238 per square metre, with a median price of €142
Insulation of unused attics: €17-93 per square metre, with a median price of €40
Heating
Wood-fired heating: €2,550 to €15,000, with a median price of €5,000
Complete replacement of the central heating system: Up to €15,000
Fuel oil condensing boiler: €3,000 and €7,000
Gas condensing boiler: €5,000 and €8,000
Heat pump: From €3,300 to €14,500 for an air-to-air heat pump; €6,400 to €21,000 for an air-water heat pump; from €13,000 to €20,000 for a geothermal heat pump
Windows and doors
For a replacement window: €250 to €1,600 per window
French window: €470 to €2,500 per window
For a replacement roof window: €450 to €1,300 per item
For a door replacement: From €750 to €3,200 per door
Ventilation
Single-flow ventilation system: €290 to €1,650
Dual-flow ventilation system: €2,700 to €7,800
Water heating
Conventional water heater: €800 to €2,200
Individual thermodynamic water heater: €2,000 to €4,600
Individual solar water heater: €4,500 to €11,500
Combined solar system: €9,800 to €22,200.
A renovation calculator such as this from the bank Crédit Agricole, can help owners to estimate the costs involved in the renovation work needed for their property. It can help you estimate different improvement scenarios, estimate your budget, and - if needed - find financial support to help.
