Energy Renovation in Luxembourg:
The Complete Guide 2026
Over 60% of Luxembourg homes are energy-inefficient. A well-planned renovation saves 50 to 80% on your bills and qualifies for up to 62.5% Klimabonus grants. This guide covers everything: priority works, steps, costs, grants and regulations.
Why carry out an energy renovation in Luxembourg?
Skyrocketing heating bills? Cold in winter, stuffy in summer? The diagnosis is clear: your home is not well enough insulated. Renovating means investing in comfort, property value and your wallet.
To drastically cut your energy bills
In Luxembourg, half of all buildings are over 45 years old and genuinely energy-inefficient. With a well-planned renovation, you can reduce heating costs by 50 to 80%. In practice: €200/month for gas or oil heating drops to €40–60/month to power a heat pump.
To improve your daily comfort
Good insulation acts as a thick barrier between you and the outside: warmth kept in during winter, coolness in summer. No more cold walls, draughts, or discomfort near windows in winter.
To increase your property value
Luxembourg property prices are among Europe’s highest. An energy renovation can increase your property’s value by 15 to 20%. Buyers pay close attention to the energy passport: an A or B-rated property sells faster and at a higher price. See our guide on how the EPC impacts property prices.
To benefit from exceptional grants
Luxembourg in 2026 offers some of Europe’s most generous energy renovation grants. The Klimabonus covers up to 62.5% of insulation costs. Add Enoprimes, 3% VAT and municipal grants: your out-of-pocket cost can be halved or more. Average payback: 8 to 12 years.
What is your renovation potential? Find out your target energy class, recommended works and eligible grants.
Simulate my potential →Priority energy renovation works
Energy renovation covers a wide range of works. To optimise your grants and savings, here is the order recommended by our experts:
Thermal insulation — the foundation
Always insulate before changing your heating system. A heat pump installed in a poorly insulated home will consume far too much electricity to be cost-effective. Roof/loft insulation (25-30% of heat loss) and exterior wall insulation (15-25%) are the absolute priorities.
→ Complete insulation guide · Roof insulation · Wall insulation
Modernise heating — switch to a heat pump
A heat pump is 3 to 5 times more efficient than a conventional boiler. It is eligible for substantial Luxembourg-specific grants. Replacing an oil boiler or gas boiler can achieve 50% savings.
Replace windows — upgrade to triple glazing
10 to 20% of heat escapes through glazed surfaces. Triple glazing is now the recommended standard in Luxembourg. See also: double vs triple glazing.
Install dual-flow ventilation
Essential in a well-insulated home to prevent humidity and renew air without losing heat. Heat recovery ventilation (HRV) recovers up to 90% of heat from stale air.
Install photovoltaic solar panels
Coupling your heat pump with solar panels allows self-powering of your heating and further reduces your electricity bill. → Solar grants 2026 · Solar ROI
Never install a heat pump before insulating your home. In a poorly insulated house, your heat pump will run continuously at full power, degrading its SCOP and tripling your electricity bill. Learn more about insulation as a heat pump prerequisite.
Thermal insulation in Luxembourg: heat losses, prices and grants by building element
As of August 2026 in Luxembourg, insulation remains the number-one lever of any energy renovation: done properly, it cuts heating needs by 40 to 70 %. In a house built between 1970 and 1990, heat escapes first through the roof (25–30 % of losses), then through external walls (20–25 %), windows (10–20 %) and ground floors (7–10 %) — a ranking that dictates the order of works.
| Insulation element | Share of heat losses | 2026 price (installed) | Klimabonus 2026 |
|---|---|---|---|
| Loft blown-in insulation | 25 – 30 % (roof) | 35 – 80 €/m² | Up to 50 % of cost with bio-based materials |
| Pitched roof (converted attic) | 25 – 30 % (roof) | 80 – 160 €/m² | Up to 50 % of cost with bio-based materials |
| External wall insulation (EWI/ITE) | 20 – 25 % (walls) | 130 – 280 €/m² | 60 €/m² standard · 85 €/m² mineral · 115 €/m² ecological (level I) |
| Internal wall insulation (IWI/ITI) | 20 – 25 % (walls) | 60 – 100 €/m² | 86.25 €/m² ecological (EWI rates reduced by 25 %) |
| Ground floor / cellar ceiling (from below) | 7 – 10 % | 25 – 45 €/m² | 35 €/m² (R ≥ 3.5) · 45 €/m² (R ≥ 4) · 55 €/m² (R ≥ 5) |
| Floor from above (in screed) | 7 – 10 % | 60 – 90 €/m² | Same ground-floor scale depending on R value |
Fossil-based insulants (EPS, PUR, XPS) have been excluded from the Klimabonus since 2024, unless they contain at least 50 % recycled content (standard rate, up to 60 €/m² on façades). On a cellar ceiling, combining the Klimabonus with the 3 % VAT rate can even exceed the invoice: a 100 m² job at R = 4 can end up at a near-zero net cost. See our detailed guides on roof and attic insulation and external wall insulation (EWI), plus all rates on our insulation cost in Luxembourg page.
Estimate your insulation grants in 2 minutes with the Renov.lu grants simulator.
Thermal bridges: how to find them and get them subsidised in Luxembourg
In 2026, thermal bridges account for 5 to 25 % of total heat losses in Luxembourg houses built before 1990 — and their share paradoxically grows as the home gets insulated: up to 25–30 % of residual losses after a partial renovation with untreated junctions. The worst offender is the cantilevered concrete balcony (1960–1985 builds), alone responsible for 10 to 20 % of the losses of an exposed storey.
| Detection / treatment | 2026 cost | Key point |
|---|---|---|
| Infrared surface thermometer (DIY check) | 15 – 80 € | A gap of 3 °C or more vs a reference surface confirms a thermal bridge |
| Professional thermography | 200 – 600 € | November to March, indoor/outdoor gap of ≥ 10 °C required |
| External wall insulation (root treatment) | 130 – 280 €/m² | Removes 70 to 90 % of thermal-bridge losses |
| Klimabonus “thermal bridge calculation” | +160 € per calculated bridge, max 800 € | Within a certified energy consultation, works completed and class C reached |
This little-known grant stacks with the energy consultation itself (up to 1,600 € for a single-family house), the quote-compliance check (100 €) and the site inspection (400 €). The reference treatment remains external wall insulation; full grant details are in our Klimabonus grants guide.
Compare up to 3 quotes from certified contractors via our free quote request.
Steps to a successful energy renovation in Luxembourg
An energy renovation can take several months, or over a year for complete projects. Here is the optimal process:
Estimate your potential (online simulation)
Start with our free simulator for an initial estimate of grants, target class and recommended works. Takes 2 minutes.
Get a free quote from a certified contractor
Contact a partner renovation company for a precise, personalised quote. Our « Made in Luxembourg » certified contractors visit for free and handle all admin.
Energy audit (mandatory for Klimabonus)
A certified expert evaluates your home and establishes a roadmap. Cost partially covered by a €1,500 state grant. Request an energy passport to know your exact situation.
Obtain Klimabonus agreement in principle
A critical step. Without prior agreement, you cannot benefit from Klimabonus grants. Your contractor usually handles this for you. Never start works without this agreement.
Carry out works with certified contractors
Works must be done by an approved company. For large projects, choose a turnkey contractor coordinating all trades.
New energy passport + grant application
After works, an expert issues a new energy passport certifying the improvement. You then submit your grant application. Maximum deadline: 4 years after works.
Ready to start your renovation?
Get up to 3 free quotes from certified contractors in Luxembourg. Reply within 48h, no commitment.
How to reach Energy Passport Class A in Luxembourg?
Older homes in Luxembourg typically have an energy passport rated F or G. The good news: rapid progress is possible with well-targeted works.
| Work combination | Achievable energy class | Bill savings |
|---|---|---|
| Loft insulation + walls | D → E (from F/G) | 30–40% |
| Full insulation + windows | C → D | 40–55% |
| Insulation + heat pump | B → C | 55–70% |
| Insulation + HP + HRV + solar | A — Passive | 70–80% |
A Class A-rated home in Luxembourg must be near-passive: enhanced insulation (20–30 cm thick), excellent airtightness, HRV ventilation, air-to-water heat pump with underfloor heating, and solar panels. An airtightness test (blower door) is generally required. Engage a certified expert to lead this type of project.
Energy renovation grants in Luxembourg for 2026
Luxembourg in 2026 offers one of Europe’s most generous sets of cumulative grants:
| Grant | Amount 2026 | Key conditions |
|---|---|---|
| 🏛️ Klimabonus | Up to 62.5% of works | Property > 10 years · Approved contractor · Energy advisory |
| ⚡ Enoprimes | ~€1,500 | Prior Enovos agreement before works |
| 🏘️ Municipal grants | €1,500 – €3,000 | Varies by municipality |
| 🏷️ 3% VAT | -14% on total invoice | Property > 10 years · Primary residence |
| 🌱 Energy advisory grant | €1,500 (audit reimbursed) | Mandatory for multi-element Klimabonus |
| 🏦 Klimaprêt | 1.5% interest subsidy | Up to €100,000 over 15 years |
Calculate your exact grants based on your property, municipality and planned works.
Calculate my grants 2026 →→ Complete Klimabonus grants guide 2026 · Heat pump specific grants · Solar panel grants
Energy renovation costs and budget in Luxembourg 2026
Prices vary depending on scope, materials and complexity. Here are the ranges observed from our partner contractors in 2026:
| Renovation type | Budget for 120 m² | Estimated grants | Net cost |
|---|---|---|---|
| Partial (1–2 elements) | €24,000 – €48,000 | 30–45% | ~€13,000 – €33,000 |
| Intermediate (insulation + HP) | €48,000 – €96,000 | 35–50% | ~€24,000 – €62,000 |
| Full renovation | €96,000 – €180,000 | Up to 62.5% | ~€36,000 – €100,000 |
→ Energy renovation cost guide · Insulation costs · Window costs · Heat pump prices
Regulatory framework for energy renovation in Luxembourg
The Grand Duchy has committed to a 55% CO₂ reduction by 2030. Building energy renovation is one of the key levers.
The Energy Passport (EPC) — mandatory for sale and rental
The energy passport is a mandatory document for all property sales and rentals. It provides an energy consumption analysis and improvement recommendations, and must be produced by a state-certified expert.
→ Energy passport cost · How to get your EPC · EPC impact on prices
Super-reduced 3% VAT
The super-reduced 3% VAT rate (instead of 17%) applies to renovation works in properties over 10 years old — a significant saving capped at €50,000 recoverable VAT.
Concrete energy renovation examples in Luxembourg
Here are two real cases completed by our partner companies in the Grand Duchy:
Example 1: Detached house in Mersch (150 m², class E → B)
Before: 1985 house, uninsulated concrete walls, weakly insulated roof, original double glazing, 25-year-old oil boiler, natural ventilation.
Works done: Exterior wall insulation (16 cm EPS), roof reinforcement (20 cm blown cellulose), high-performance double glazing, air-to-water heat pump, HRV ventilation, 6 kWp solar panels.
Example 2: Apartment in Luxembourg City (80 m², class F → C)
Before: 1970s apartment, uninsulated concrete walls, single glazing, direct electric heating, no ventilation.
Works done: Interior wall insulation (8 cm wood fibre), high-performance double glazing, air-to-air heat pump (multisplit), humidity-controlled ventilation, thermodynamic water heater.
Energy renovation of a single-family house: 3 costed scenarios
In Luxembourg in 2026, the energy renovation of a single-family house ranges from 6,250 € (roof only) to 80,000 – 150,000 € for the full renovation of a 130 m² home. Houses make up 45.9 % of the housing stock; the Klimabonus Wunnen covers 50 % of eligible costs for multi-measure projects with an energy consultation, 60 % from +2 EPC classes and 62.5 % (cap) from +3 classes — plus a 2,000 € bonus if class A or B is reached.
| Scenario | Total incl. 3 % VAT | Estimated aid | Out-of-pocket | EPC gain |
|---|---|---|---|---|
| A — Roof only (130 m², 1980s, class G) | 6,250 € | ≈ 3,375 € | ≈ 2,875 € | G → F-E |
| B — Insulation + heat pump + windows (130 m², 1985, class F) | 44,200 € | ≈ 23,700 € | ≈ 20,500 € | F → C-D |
| C — Full renovation (150 m², 1975, class H, ground-source heat pump + solar PV) | 142,500 € | ≈ 69,450 € | ≈ 73,050 € | H → A/B |
The social top-up can further cut the out-of-pocket amount (up to −22,000 € on scenario C), and a full renovation raises property value by an estimated +15 to 20 %. Full conditions and amounts in our Klimabonus 2026 grants guide; the order of formalities in our energy renovation steps in Luxembourg.
Cost your own scenario with the Renov.lu grants simulator.
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Frequently asked questions about energy renovation in Luxembourg
What is energy renovation in Luxembourg?
Energy renovation improves a home’s energy efficiency to reduce consumption and environmental impact. It typically includes thermal insulation (walls, roof, floors), installation of a heat pump, window replacement, and HRV ventilation.
Why renovate in 2026 in Luxembourg?
The 2026 Klimabonus Wunnen grants are among the most generous ever offered — up to 62.5% of insulation works. Works must be invoiced before 31 December 2030. Energy savings reach 50–80%, and property values increase by 15–20%. Use our free simulator to estimate your potential.
Which works are the priority?
Thermal insulation is the absolute priority, before changing the heating system. Start with the loft (25-30% of heat loss), then exterior walls (15-25%). Only then install a heat pump. See our guide on where to start.
How much does energy renovation cost in Luxembourg?
From €24,000 (partial renovation of a 120 m² home) to €180,000 for full renovation. With Klimabonus grants (up to 62.5%), 3% VAT and Enoprimes, your out-of-pocket cost can be more than halved. See our renovation cost guide.
How long does it take to recoup the investment?
On average 8 to 12 years, thanks to energy savings and financial grants. For very energy-inefficient homes (class F or G), this can be reduced to 6–7 years due to the larger savings achieved.