Klimabonus 2026: the per-square-metre rate for roof insulation in Luxembourg

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 pays a rate per square metre refurbished: from 35 to 115 EUR/m² depending on the insulant and the performance standard reached, and up to 140 EUR/m² with the transitional increase (agreement in principle applied for between 01/01/2026 and 30/06/2027, invoice by 31/12/2030 at the latest). 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, meeting the age requirement (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 per Square Metre

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

Note that the amount is proportional to the area actually refurbished: it is not a percentage of the quote. Insulation fitted exclusively on the inside is reduced by 25%, while a mineral insulant more than 50% recycled, an ecological insulant from certified sustainable crops, or a green roof each add 15 EUR/m².

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 meeting the age requirement. This rate applies to labor and materials, provided the company invoices the client directly. Where the conditions are not met, 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 a mineral insulant reaching standard II, the rate is 70 EUR/m², i.e. 7,000 EUR of aid for the 100 m² refurbished — and 8,000 EUR with the transitional increase. Aiming for standard I with an ecological insulant (115 EUR/m², 140 EUR/m² increased) raises the aid to 11,500 EUR, or even 14,000 EUR. On top of that, VAT at 3% (900 EUR on 30,000 EUR) instead of 17% (5,100 EUR) saves a further 4,200 EUR.

Another example: attic insulation for a 50 m² area, quote of 12,000 EUR. With a mineral insulant at standard III (60 EUR/m²), the aid is 3,000 EUR, rising to 3,500 EUR with the transitional increase.

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).