Klimabonus 2026: Up to 50% for Roof Insulation in Luxembourg (Max 15,000 EUR)

What is the Klimabonus Wunnen 2026?

The Klimabonus Wunnen 2026 is the new financial aid program for energy renovation in Luxembourg, launched by the government in January 2026. It replaces the former PRIMe House program (valid until 31 December 2025) and aims to encourage homeowners to improve the energy efficiency of their homes. The goal is to reduce CO2 emissions and lower household energy bills. This program is managed by the Klima-Agence in collaboration with the one-stop shop (MyGuichet.lu).

For roof insulation, the Klimabonus offers up to 50% of eligible costs, with a cap of 15,000 EUR per dwelling. This aid can be combined with other subsidies, such as those for photovoltaic panels (up to 10,000 EUR) or home batteries (up to 2,250 EUR).

Eligibility Conditions for Roof Insulation

To benefit from the Klimabonus for roof insulation, several conditions must be met:

• Eligible dwelling: Main or secondary residence located in Luxembourg, built more than 2 years ago (otherwise standard VAT of 17% applies instead of 3%).
• Minimum performance: Insulation must achieve a thermal resistance of R >= 6 m²K/W for sarking (external insulation) or R >= 7 m²K/W for attic insulation (internal insulation).
• Materials: Use of insulating materials compliant with Luxembourg standards (glass wool, rock wool, polyurethane, etc.).
• Approved company: Work must be carried out by a professional registered in Luxembourg (roofer, general contractor).

Additionally, the work must be declared to the commune and comply with applicable urban planning rules.

Aid Amounts and Caps

The table below summarizes the key amounts of the Klimabonus for roof insulation:

Note that the cap of 15,000 EUR applies to all roof insulation work per dwelling. If you combine several types of insulation (e.g., sarking and attic), the total cumulative amount cannot exceed this limit.

How to Apply?

The application procedure is entirely online via MyGuichet.lu, the official portal for administrative procedures in Luxembourg. Here are the steps:

1. Get a quote: Contact a qualified artisan to obtain a detailed quote for the insulation work.
2. Create a file: Log in to MyGuichet.lu with your ID (or create an account). Select the form "Klimabonus Wunnen - Aid application".
3. Submit the quote: Attach the quote signed by the artisan and fill in the required information (area to insulate, materials, expected performance).
4. Receive approval: The Klima-Agence processes your application within 4 to 6 weeks. Once approved, you receive an approval letter valid for 12 months.
5. Carry out the work: Have the work done by the artisan within the given timeframe.
6. Request payment: After the work, submit the paid invoice and proof of performance (certificate from the artisan or thermal measurement). Payment is made within 2 to 3 months.

Important: the application must be made before the start of work, otherwise the aid is refused.

Additional Tax Benefits

In addition to the Klimabonus, homeowners can benefit from a super-reduced VAT rate of 3% on energy renovation work, provided the home was completed more than 2 years ago. This rate applies to labor and materials, provided the company invoices the client directly. For homes less than 2 years old, the standard rate of 17% applies.

Furthermore, loan interest for financing the work may be deductible from rental income (if the property is rented) or qualify for a tax credit under certain conditions. Check with the Administration des contributions directes.

Concrete Financing Examples

Take the example of a single-family home in Luxembourg City with a 100 m² roof to insulate using sarking. The artisan's quote amounts to 30,000 EUR (materials and labor). With the Klimabonus at 50%, the maximum aid is 15,000 EUR (cap reached). The homeowner thus pays only 15,000 EUR out of pocket, plus VAT at 3% (i.e., 450 EUR) instead of 17% (5,100 EUR), resulting in additional savings of 4,650 EUR. In total, the real cost after aid and reduced VAT is approximately 15,450 EUR, a reduction of nearly 50% from the initial price.

Another example: attic insulation for a 50 m² area, quote of 12,000 EUR. The Klimabonus covers 50% or 6,000 EUR (cap not reached). With VAT at 3%, the final cost is about 6,360 EUR.

Tips to Maximize Your Aid

• Get multiple quotes: Compare offers from at least 3 artisans to get the best value for money.
• Check performance: Ensure the proposed insulation achieves R>=6 or R>=7. Ask for a technical data sheet.
• Anticipate delays: Applications are processed within 4 to 6 weeks. Do not start work before approval.
• Keep all documents: Quotes, invoices, performance certificates are needed for payment.
• Combine aids: If you also install solar panels or a heat pump, you can combine subsidies (within the limits of the caps).