Energy performance assessment and sale of your mountain property
Here’s what you need to bear in mind:
- An energy performance audit is compulsory from the moment a preliminary sale agreement is signed for properties classified as E, F or G
- Mountain properties are subject to climatic conditions that increase their energy consumption
- Targeted improvements can boost your energy rating and increase the value of your property by 5 to 15 per cent
If you’re looking to invest rather than sell, browse our catalogue for apartments for sale in Méribel.
What is an ‘energy audit’?
An energy audit is an in-depth assessment that evaluates a building’s energy and environmental performance, then proposes concrete renovation scenarios. It is not limited to a label: it provides the buyer with a costed roadmap.
Don’t confuse this with the Energy Performance Certificate (EPC). The Energy Performance Certificate simply assigns a grade (A to G), and that’s it. The audit goes further: it identifies the building’s weaknesses and details the work required to rectify them.
Another notable difference is that the audit is valid for 5 years, compared with 10 years for the EPC. We outlined the finer points of the EPC in our article on the EPC and holiday rentals in the mountains.
Will an energy audit be compulsory in 2026?
Yes, and even before then. From January 2025, any owner selling a property classified as E, F or G must provide the buyer with a statutory energy audit. The timetable has been brought forward in recent years, and mountain properties are at the forefront of these changes.
Which properties are affected?
The properties in question are detached houses and single-ownership blocks of flats. In practical terms, if you own a chalet in Méribel-Mottaret or a self-contained holiday home in La Tania, you are affected provided the energy rating is E, F or G.
Flats in co-ownership schemes are currently exempt from this requirement. The extension to properties rated D is scheduled for 2034.
Key dates to note
- From April 2023: requirement for properties rated F and G
- From January 2025: extension to properties rated E
- From 2034: extension to properties rated D
The energy performance certificate must be submitted no later than the signing of the preliminary sale agreement or the final deed of sale. Not after. Failure to do so could block the transaction!
Some specific features of the energy performance audit for mountain properties
Properties situated at high altitudes, between 1,100 m and 2,000 m in the 3 Vallées, face climatic constraints that the standard energy performance certificate (DPE) struggles to reflect accurately. The calculation includes adjustments for cold zones, but the result is often still unfavourable.
Why?
Because heating requirements skyrocket above 1,500 m.
A chalet in Méribel-Mottaret (1,750 m) inevitably consumes more energy than an equivalent property in the valley. Reduced sunlight on the north-facing slope further worsens the energy balance…
Traditional building materials also raise questions:
- Wood and stone, which are ubiquitous in mountain buildings, offer varying thermal performance depending on how they are used.
- Pitched roofs, whilst effective at shedding snow, can sometimes create thermal bridges that are difficult to address without altering the character of the building.
One final point that is often underestimated: seasonal occupancy. A property used for 12 weeks a year has a theoretical energy consumption that differs significantly from reality. This discrepancy can work against you during the audit. To better understand the long-term challenges, our analysis of investment in mountain properties in the face of global warming provides further insight.
What does the statutory energy audit involve?
The statutory audit comprises two inseparable parts: a comprehensive assessment of current performance, followed by costed proposals for improvement works. Nothing is left to chance.
An energy assessment to gauge the ‘reliability’ of your property
The assessor scrutinises six key areas:
- insulation (walls, floors, roof)
- Windows and doors
- Heating
- Hot water supply
- Ventilation
- Lighting
Each category is given a score.
The audit also identifies thermal bridges and airtightness defects, two recurring weaknesses in mountain buildings from the 1970s to the 1990s.
Proposed works that you cannot avoid
The audit must include at least two renovation scenarios:
- a phased approach (work carried out in stages)
- and a single-phase approach.
The stated objective is to achieve energy efficiency class B, or C if technical or heritage constraints prevent this.
Each scenario includes a cost estimate and a list of available financial assistance (MaPrimeRénov’, energy-saving certificates). The proposed works must be consistent with one another and respect the existing building structure.
Who can carry out the energy audit… and at what cost?
Only qualified professionals may carry out the audit: certified energy auditors, trained architects or RGE-accredited professionals. Subcontracting is prohibited, and an on-site visit is mandatory. No one may carry out an audit remotely.
As for the cost, rates are not regulated. They vary depending on the size of the property and its technical complexity.
|
Type of property |
Price range |
|
Studio / small flat |
€500 to €800 |
|
Detached chalet |
€800 to €1,500 |
|
Large property |
€1,200 to €1,500+ |
Good news: MaPrimeRénov' can cover part of the cost of the energy audit, subject to means testing. Find out more before hiring a professional.
How can you increase your property’s value despite a poor energy rating?
An E, F or G rating isn’t a death sentence. You have two options: renovate before selling, or be transparent about it during negotiations.
Consider carrying out work before the sale
Certain investments offer a quick return on the final sale price. In order of priority:
- Loft insulation: the most cost-effective improvement, particularly in mountainous areas where heat loss through the roof can reach 30%
- Replacing the heating system: switching from an oil-fired boiler to a heat pump drastically improves the energy rating
- Double-glazed windows and an efficient mechanical ventilation system to complete the thermal envelope
Combining the MaPrimeRénov’ and CEE schemes can reduce the cost by 30 to 50 per cent, depending on your income. The impact on the sale price is a gain of between 5 and 15 per cent, depending on the scale of the improvements.
Be transparent during negotiations
Don’t want to carry out any work? Be methodical. Provide the energy audit at the very first viewing, not just when it’s time to sign. Buyers hate unpleasant surprises.
Give a precise breakdown of the work required and propose a price negotiation that takes this cost into account. An informed buyer would rather have an adjusted price than deal with a seller who hides the truth.
Highlight what the audit doesn’t measure: the ski-in/ski-out location, the view of the Saulire, and the proximity to the ski lifts. These assets remain decisive in the 3 Vallées.
FAQ: everything you need to know about energy audits and selling your property in the mountains
Is an energy audit compulsory when selling a flat in a holiday residence in the 3 Vallées?
No. Flats in co-ownership schemes are not subject to the mandatory energy audit. Only the Energy Performance Certificate (EPC) is required.
What is the difference between the DPE and an energy audit for a mountain property?
The DPE assigns an energy efficiency rating. The audit goes further by proposing costed renovation scenarios tailored to the building’s specific constraints.
Are the improvements proposed in the audit compulsory before the sale?
No. The audit informs the buyer of possible improvements, but the seller is under no obligation to carry out the work before the sale.
Is an energy audit carried out in 2024 still valid in 2026?
Yes. The audit is valid for five years from the date it was carried out. An audit from 2024 therefore remains valid until 2029.

