Faced with changing energy regulations and buyer expectations, thermal strainer owners find themselves faced with a dilemma: sell at a discount or invest in renovations. This choice is based on several factors: cost of work, location, and impact on the sale price. Here is a complete analysis, with quantified scenarios, to help you make the best decision in 2025.
Cost of energy renovations: a heavy but profitable investment?
The average cost of improving the energy performance of a property depends on its initial class and the work necessary to achieve class D or C. In 2025, here is an estimate of the average costs:
- Class G → Class D: Between €20,000 and €30,000 for a 100 m² house.
- Class F → Class C: Between €15,000 and €25,000.
- Class G → Class C: Up to €40,000 for major work (insulation, heating, windows).
These amounts include aid available such as MaPrimeRénov', which can cover up to €10,000 depending on income.
Breakdown of energy renovation costs
How will energy renovation expenses be distributed in 2025? Insulation, heating, and joinery represent the main cost items, essential for improving the energy class of a property
Discount in the event of sale without renovation
Thermal strainers experience significant loss of value. In 2025, the average discount observed is as follows:
- Class G: -25% to -30% of the average market price.
- Class F: -15% to -20%.
- Class E: -5% to -10%.
For example, for a house valued at €200,000 in an average area:
- In class G, it could sell for around €150,000 (-25%).
- In class F, it would sell for around €170,000 (-15%).
The weight of energy-intensive housing on the real estate market
In 2025, energy-intensive housing will continue to weigh heavily on the real estate market. According to notaries, nearly 17% of transactions in 2023 concerned properties classified F or G in the energy performance diagnosis (DPE)a figure in constant evolution. The market discount for these properties is significant, sometimes reaching up to 25% of the initial price in tense areas such as Paris or Lyon. This trend pushes owners to ask themselves: should we invest in work to improve the energy class or sell quickly by accepting a price reduction? This decision depends largely on access to public aid, the location of the property, and the profile of the owners themselves.
-Besides, did you know that? Some regions are more impacted than others by thermal strainers.
Senior homeowners face the renovation dilemma
Among the owners concerned, 23% are seniors, often reluctant to carry out heavy work on their property. For these owners, the idea of “keeping your thermal strainer” may seem more interesting, especially if the accommodation is intended to be sold or transferred in the short term. Public aid such as MaPrimeRénov' or Energy Savings Certificates offer solutions, but they only cover part of the costs. Thus, for seniors, the decision to sell or renovate is often based on short-term profitability and the financial implications of a discount.
Making a thermal strainer profitable: is it possible?
For some owners, particularly investors, it is always possible to make a profit from energy-intensive housing. By maintaining it as a short-term rental (within legal limits), they can amortize maintenance costs while enjoying regular income. However, the viability of this strategy depends on geographic areas: in rural areas, energy-intensive properties experience less pressure on their discount, while in large cities, the urgency of renovations is amplified by competition in the real estate market.
Public aid and financial support: an opportunity not to be overlooked
The French government continues to strengthen aid schemes to encourage the renovation of thermal strainers. In 2025, programs like MaPrimeRénov' or the eco-PTZ (zero interest loan) remain essential tools for owners looking for affordable solutions. Low-income households can obtain up to €10,000 in grants for insulation or heating change work. By combining this aid with local measures, it becomes possible to reduce the costs of the work, making the renovation more attractive than selling at a reduced price.
Typical scenarios according to budgets and geographic areas
Scenario 1: House in a tense area (Paris, Lyon)
- Initial value (class G): €400,000.
Discount in the event of a sale without work: -30% (i.e. a sale for €280,000). - Cost of work to upgrade to class C: €40,000.
Value after renovation: €420,000 (revalued price).
Conclusion: Profitable renovation with a potential net gain of €100,000 (€420,000 – €280,000 – €40,000).
Scenario 2: House in an average area (Angers, Dijon)
- Initial value (class F): €200,000.
Discount in the event of a sale without work: -15% (i.e. a sale at €170,000). - Cost of work to upgrade to class D: €20,000.
Value after renovation: €210,000.
Conclusion: Renovation slightly profitable, but less marked (+€20,000 net gain).
Scenario 3: House in rural area
- Initial value (class G): €150,000.
Discount in the event of a sale without work: -30% (i.e. a sale at €105,000). - Cost of work to upgrade to class D: €25,000.
Value after renovation: €155,000.
Conclusion: Limited gain (€25,000); selling without work can be a viable option depending on the budget.
