Insulation grants and subsidies in Luxembourg in 2026: the complete guide
Isoleaz assists you with the insulation of your facade in Luxembourg
Renovating your home for energy efficiency requires a significant budget, which often causes hesitation. However, the benefits accumulate year after year: lower heating bills, a more comfortable interior, and a property whose value is better maintained over time. To ensure that Luxembourg homeowners are not left to shoulder this financial burden alone, the government has progressively established a range of support programs, among the most comprehensive in Europe. Isoleaz explains how these programs work and how to make the most of them for your project.
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Why are energy renovation grants essential in 2026?
Energy costs are taking an increasingly heavy toll on household budgets. In Luxembourg, annual inflation is projected at 2.1% in 2024 and 2.3% in 2025, according to STATEC, and heating, electricity, and gas are directly impacted. Many homeowners pay significantly higher bills each winter than the cost of a properly insulated home would represent.
The Luxembourg government has been quick to react: the aid system put in place aims precisely to ensure that renovations are not reserved for those who can already afford them. Added to this is a climate imperative: the residential sector accounts for a significant portion of national CO₂ emissions, and every completed renovation contributes to the Grand Duchy’s environmental trajectory.
Summary of aid that can be combined in 2026
Here are the main funding mechanisms available for insulation work in Luxembourg:
- Klimabonus Wunnen: aid calculated in €/m² according to the material and performance achieved, with an additional charge for bio-based insulation and a social top-up for low-income households.
- Reduced VAT rate of 3%: applicable to primary residences older than two years
- Enoprimes: variable amount depending on energy savings generated, offered by several suppliers (including Enovos and SUDenergie), subject to prior agreement before signing the quote
- Municipal aid: from €1,500 to €3,000 depending on the municipality, often linked to the Climate Pact
- Energy consulting reimbursement: up to €1,500
- Klimaprêt: up to €100,000 over 15 years with a 1.5% interest bonus (capped at 10% of the capital)
The Klimabonus Wunnen: the central system for helping with insulation
How does the Klimabonus work?
Among all the aid mechanisms available in Luxembourg, the Klimabonus Wunnen occupies a unique position. Managed by the Environment Agency, it operates on a fixed-rate basis, expressed in euros per square meter, and adjusted according to the chosen insulation material and the performance level achieved. The more ambitious the insulation project, the higher the subsidy (source: Guichet.lu).
In 2026, each fixed rate takes into account the chosen insulation material and the actual thermal resistance level achieved on the construction site. For homeowners, the advantage is tangible: the amount of the subsidy is calculated precisely well before work begins.
Note: the Klimabonus Wunnen has succeeded the PRIMe House program, which it has completely replaced. All applications submitted in 2026 fall exclusively under the Klimabonus scheme. References to PRIMe House are no longer valid.
| Device | Work covered | Amount/benefit | Key conditions | Cumulative |
|---|---|---|---|---|
| Klimabonus Wunnen (Climate Bonus for Housing) Main bonus | Insulation for walls, roof, attics, floors+€45/m² if bio-based material (wood fiber, hemp, sheep's wool) | Flat rate €/m² Calculated based on material + level of thermal performance achieved Social top-up: amount doubled for low-income households | Building > 10 years of experience as an approved energy consultant is mandatory for multi-element renovations; a file must be submitted before work begins. Invoices before 31/12/2030 (isolated works) or 31/12/2035 (comprehensive renovation) | ✓ yes |
| Reduced VAT rate of 3% Tax reduction | Insulation for walls, roofs, attics, and floors in primary residences | -14 points of VAT 3% instead of 17% — applied directly to the invoice, no paperwork required | Primary residence, age > 2 years, no income ceiling, no application required | ✓ yes |
| Enoprimes (energy-efficiency subsidy program) Supplier help | Energy renovation generating measurable savings (insulation, heating, etc.) | Variable Calculated based on energy savings generated — the greater the gain, the higher the bonus | ⚠ Prior agreement is mandatory before signing any quote — no recourse is possible afterwards Offered by Enovos, SUDenergie and other operators active on the national network | ✓ yes |
| Municipal aidLocal help | Residential insulation — depending on the municipality (e.g., Strassen, Mamer…) | 1 500 – 3 000 € Depending on the location and the nature of the work carried out | Rules vary by municipality and are often linked to the Climate Pact; contact the technical or urban planning department of your municipality. | ✓ yes |
| Energy consultingRefund | Energy audit prior to work | Up to €1,500 Reimbursement of the audit cost and free support via Klima-Agence | An accredited energy advisor is mandatory if several building elements are renovated simultaneously to benefit from the Klimabonus. | ✓ yes |
| Climate Loan Funding | Insulation, heating replacement, ventilation — comprehensive projects | Up to €100,000 Over 15 years, a 1.5% interest subsidy is provided by the State (capped at 10% of the borrowed capital). | Through an approved partner bank suited to projects exceeding self-financing capacity | ✓ yes |
Sources: Guichet.lu, Environment Administration, Klima-Agence, enoprimes.lu, pacteclimat.lu
What's new with the Klimabonus in 2026
Several adjustments have come into effect this year:
- Wood fiber, hemp, sheep’s wool: bio-based materials qualify for an additional bonus of €45/m², a clear signal of a desire to steer choices towards insulation with a low environmental footprint.
- A “social top-up” has been introduced for low-income households, with the possibility of doubling the basic amounts to which they are entitled.
- Invoices for the work must be established before December 31, 2030 for an isolated intervention, and before December 31, 2035 when they are part of an overall renovation of the building (source: Guichet.lu)
Eligibility conditions for the Klimabonus
Before submitting an application, several criteria must be checked:
- The property must be more than 10 years old.
- The work must be entrusted to an approved company.
- A preliminary energy assessment is mandatory when the renovation affects several elements of the building at the same time.
- The application must be submitted before the start of construction.
Reduced VAT at 3%: an immediate saving on the bill
Few schemes are as easy to activate. In Luxembourg, any renovation carried out on a primary residence that is more than two years old benefits from a reduced VAT rate of 3% instead of 17% (source: Luxembourg Registration, Estates and VAT Administration). On an insulation bill, this 14-point difference represents an immediate and significant saving, without any paperwork to fill out.
Insulation work on walls, roofs, attics, and floors automatically falls under this scheme, provided the property meets the age requirement. There is no income ceiling: all eligible homeowners benefit automatically upon receiving their invoice.
The Enoprimes: additional aid to plan ahead for
Several Luxembourg energy suppliers (including Enovos, SUDenergie, and other operators active on the national grid) offer additional grants to homeowners undertaking energy renovation work. Grouped under the Enoprimes program, these grants can be combined with the Klimabonus and are calculated based on the actual energy savings generated by the work: the greater the savings, the higher the grant. Prior agreement is absolutely required before signing any quotes, otherwise the grant will be permanently forfeited (source: enoprimes.lu).
The eligibility requirement for Enoprimes is often underestimated: the agreement must be obtained before any quotes are signed, which goes further than the Klimabonus. Once this point is reached, the application is inadmissible (without exception or appeal). In practice, this process must begin in the first few weeks of project preparation, at the same time as the Klimabonus application.
Municipal aid: up to €3,000 depending on your municipality
National schemes are not the only available option. Some Luxembourg municipalities have developed their own energy efficiency renovation support programs, independent of state aid. Depending on the municipality, this support can amount to between €1,500 and €3,000 for residential insulation work. Strassen and Mamer are among the municipalities that have structured this type of local approach.
These municipal initiatives are often part of the Climate Pact, a national program coordinated by the Klima-Agence (Luxembourg Climate Agency) that encourages municipalities to integrate concrete energy transition measures, including financial support for private renovations (source: pacteclimat.lu).
The eligibility criteria vary considerably from one municipality to another, both in terms of the amounts granted and the types of work covered. Contacting your municipality’s technical or urban planning department directly remains the most reliable way to find out what you are eligible for. These local subsidies can generally be combined with national schemes, which can further reduce the final cost.
The Klimaprêt: financing long-term investment
Some renovation projects exceed a household’s self-financing capacity, even when taking available subsidies into account. The Klimaprêt loan was designed for these situations: it allows you to finance up to €100,000 worth of work over a period of up to 15 years, through an approved partner bank, with a 1.5% interest subsidy covered by the government – capped at 10% of the loan amount (source: Klima-Agence).
This loan is particularly well-suited to comprehensive projects combining insulation, heating system replacement, and the installation of controlled mechanical ventilation. For a 120 m² home, the budget ranges from €24,000 to €180,000 depending on the scope of the work, with the remaining cost estimated between €36,000 and €100,000 after subsidies are deducted.
Energy consulting: an audit reimbursed up to €1,500
Consulting a certified energy advisor before starting any work is a useful precaution, and even mandatory when the renovation involves several elements of the building simultaneously in order to qualify for the Klimabonus Wunnen grant.
What makes this approach even more attractive is that the cost of this audit can be reimbursed up to €1,500 under existing programs. The Klima-Agence also offers free support to individuals who want to better understand the energy performance of their home and prioritize the necessary improvements (source: Klima-Agence).
How to submit your application for assistance?
Procedures via Guichet.lu
Most applications for energy renovation grants are submitted online via the Guichet.lu platform, which centralizes administrative procedures related to Luxembourg public aid. After creating or logging into a personal account, the applicant completes the form corresponding to the program in question and attaches the required supporting documents.
Documents usually requested
To compile a complete application, the following documents are usually required:
- Detailed quote or invoices for work carried out
- Proof of identity and residence in Luxembourg
- Energy Performance Certificate (EPC) of the dwelling
- Certificate from the approved company that carried out the work
- Documents relating to household composition, according to the scheme concerned
Any incomplete application will result in additional delays, or even rejection of the application. It is therefore advisable to gather all the required documents before submitting the application.
Common mistakes to avoid
Several pitfalls are regularly observed during the preparation of the files:
- Starting work before obtaining prior approval for the Enoprimes or Klimabonus schemes will render the application inadmissible.
- Relying on outdated scales: the amounts and eligibility conditions change every year; it is essential to consult the references in force for 2026.
- Neglecting local aid: many homeowners are unaware of these local programs, which can represent several thousand euros in additional savings.
- Forgetting to combine schemes: reduced VAT, Klimabonus, and municipal aid can often be combined, significantly reducing the final cost
Isoleaz will assist you with your procedures.
Navigating the Luxembourg aid system can be complex for individuals. There are numerous programs, specific eligibility requirements, and often crucial deadlines. Isoleaz has in-depth knowledge of these mechanisms and supports you at every stage: identifying available aid, preparing applications, coordinating with relevant organizations, and handling the administrative follow-up until the aid is disbursed.
Our teams are fully familiar with the technical requirements for the work carried out to qualify for the various programs. By entrusting your project to Isoleaz, you maximize your chances of obtaining the aid you are entitled to, while benefiting from insulation installed to the highest standards.
Want to assess the aid your project qualifies for in Luxembourg? Contact Isoleaz for free, personalized support and start your energy renovation with complete peace of mind.
Do you want to insulate your home?
Ask our team of experts for advice