Loft Insulation Prices in Luxembourg 2026: Costs & Klimabonus
At a glance
- Average price to insulate lost attic space in Luxembourg in 2026 ranges from 25 to 55 EUR per m², including blow-in or roll installation.
- Klimabonus Wunnen 2026 replaces PRIMe House from January 2026 and covers up to 50% of loft insulation costs, capped at 15,000 EUR (R ≥ 7 for lost attics).
- The super-reduced VAT of 3% applies for homes older than 2 years, significantly reducing the final bill.
- For a typical 100 m² attic, expect between 2,500 and 5,500 EUR before subsidies, and between 1,250 and 2,750 EUR after Klimabonus.
- Using a certified craftsman and meeting technical criteria (R ≥ 7) is essential to obtain Klimabonus Wunnen 2026.
Table of contents (8)
- 1. Why insulate your lost attic in Luxembourg in 2026?
- 2. Different types of lost attic insulation
- 3. Loft insulation prices in Luxembourg in 2026
- 4. Klimabonus Wunnen 2026: an essential financial aid
- 5. Typical calculation example for a single-family house
- 6. Criteria to meet for Klimabonus
- 7. How to choose your craftsman for loft insulation?
- 8. FAQ: Loft insulation prices in Luxembourg
Key information
| Average price for loft insulation (blow-in) | 25 to 40 EUR/m² |
| Average price for loft insulation (rolls) | 30 to 55 EUR/m² |
| Klimabonus Wunnen 2026 subsidy | Up to 50% of cost, cap 15,000 EUR (R ≥ 7) |
| Applicable VAT (home > 2 years) | 3% (super-reduced) |
| Typical lost attic surface | 80 to 120 m² for a single-family house |
| Total cost before subsidies (100 m²) | 2,500 to 5,500 EUR |
| Total cost after Klimabonus (100 m²) | 1,250 to 2,750 EUR |
| Estimated annual heating savings | 300 to 800 EUR depending on system |
« The Klimabonus Wunnen 2026 offers up to 50% subsidy for loft insulation, with a cap of 15,000 EUR, provided you meet a thermal resistance coefficient R ≥ 7 for lost attics. »
Why insulate your lost attic in Luxembourg in 2026?
In Luxembourg, lost attics often represent the largest source of heat loss in a house. According to figures from the Ministry of Energy, up to 30% of heat can escape through a poorly insulated roof. In 2026, with continuously rising energy prices and the entry into force of Klimabonus Wunnen, insulating your lost attic has become a priority for many homeowners.
The Klimabonus Wunnen 2026, managed by Klima-Agence and accessible via guichet.public.lu, has replaced PRIMe House since January 2026. This new scheme offers up to 50% subsidy for loft insulation, with a cap of 15,000 EUR, provided you meet a thermal resistance coefficient R ≥ 7 for lost attics. This is a major opportunity to reduce your energy bill while adding value to your property.
Different types of lost attic insulation
There are mainly two techniques for insulating lost attics in Luxembourg:
- Blow-in insulation: mineral wool or cellulose flakes are mechanically projected onto the attic floor. This method is fast, seamless, and particularly suitable for hard-to-reach attics. It offers excellent value for money.
- Roll or panel insulation: rolls of glass wool, rock wool, or natural fibers are unrolled onto the floor. This technique is more accessible for DIY enthusiasts, but it requires careful installation to avoid thermal bridges.
The choice depends on your attic configuration, budget, and performance goals. A certified craftsman can guide you to the most suitable solution.
Loft insulation prices in Luxembourg in 2026
Prices vary according to technique, material, and surface area. Here is a summary table of average rates in Luxembourg in 2026:
| Type of insulation | Average price (EUR/m²) | Cost for 100 m² |
|---|---|---|
| Mineral wool blow-in | 25 to 35 EUR | 2,500 to 3,500 EUR |
| Cellulose blow-in | 30 to 40 EUR | 3,000 to 4,000 EUR |
| Glass wool rolls | 30 to 45 EUR | 3,000 to 4,500 EUR |
| Rock wool rolls | 35 to 55 EUR | 3,500 to 5,500 EUR |
| Bio-sourced insulation (wood fiber) | 45 to 65 EUR | 4,500 to 6,500 EUR |
These prices include labor, materials, and installation. They may vary depending on attic accessibility, presence of technical equipment (VMC, chimney), and region.
Klimabonus Wunnen 2026: an essential financial aid
Since January 2026, Klimabonus Wunnen replaces PRIMe House and simplifies procedures for Luxembourg homeowners. For lost attic insulation, the aid covers 50% of the work cost, capped at 15,000 EUR, provided the insulation achieves R ≥ 7. For pitched roof insulation (sarking), the threshold is R ≥ 6.
Other Klimabonus Wunnen 2026 aids include:
- Photovoltaic installation: up to 10,000 EUR (about 8,300 EUR for 10 kWp, maximum reached from 15 kWp).
- Home battery: up to 2,250 EUR.
- Window replacement: 70 EUR per m² of glazing replaced.
To benefit from these aids, it is imperative to use a qualified craftsman and meet technical criteria. Applications are made via the guichet.public.lu portal or directly with Klima-Agence.
Typical calculation example for a single-family house
Take the illustrative case of a single-family house with 100 m² of lost attic in Luxembourg City. The owner opts for mineral wool blow-in at 35 EUR/m², for a total cost of 3,500 EUR excluding VAT. With the super-reduced VAT of 3% (home older than 2 years), the cost including VAT is 3,605 EUR.
Thanks to Klimabonus Wunnen 2026, they obtain a 50% subsidy, i.e., 1,802.50 EUR. Their final net cost is therefore 1,802.50 EUR. With estimated heating savings of 500 EUR per year, the return on investment is about 3.6 years. This illustrative case shows the financial benefit of insulating your lost attic in Luxembourg.
Criteria to meet for Klimabonus
To be eligible for Klimabonus Wunnen 2026, several conditions must be met:
- The home must be located in Luxembourg and completed more than 2 years ago.
- The work must be carried out by a registered craftsman.
- Lost attic insulation must achieve R ≥ 7 (R ≥ 6 for sarking).
- The application must be submitted before work begins (or within the required deadlines).
- Invoices and proof of payment must be kept.
It is recommended to consult an energy advisor to validate your project's compliance before signing a quote.
How to choose your craftsman for loft insulation?
The Luxembourg market has many craftsmen specializing in insulation. To make the right choice, check:
- The company's certifications and labels (e.g., "Certified Craftsman" label).
- References and customer reviews.
- Clarity of the quote: materials, thickness, thermal R, applicable VAT.
- Professional liability insurance.
Do not hesitate to request several quotes for comparison. A price gap that is too large should alert you to the quality of materials or installation.
FAQ: Loft insulation prices in Luxembourg
Below are the most frequently asked questions from Luxembourg homeowners.
Frequently asked questions
The average price ranges from 2,500 to 5,500 EUR for 100 m², depending on the technique (blow-in or rolls) and material. After deducting Klimabonus Wunnen 2026 (50%), the net cost can drop to between 1,250 and 2,750 EUR.
Yes, since January 2026, Klimabonus Wunnen replaces PRIMe House. It offers up to 50% subsidy for lost attic insulation, with a cap of 15,000 EUR, provided you meet R ≥ 7.
For homes older than 2 years, the super-reduced VAT of 3% applies. For new homes or those less than 2 years old, the normal rate of 17% applies.
For lost attics, you must achieve R ≥ 7. For pitched roof insulation (sarking), the threshold is R ≥ 6. This corresponds to an insulation thickness of 30 to 35 cm depending on the material.
The return on investment is generally between 4 and 7 years, taking into account heating savings and subsidies. With Klimabonus Wunnen 2026, it can be reduced to 3 or 4 years in some cases.
Sources
Data verified in April 2026
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