How much does heat recovery ventilation (MVHR) cost in Luxembourg, and what grant is available?
By Yacine Sahnoune, founder of renov.lu
In Luxembourg, heat recovery ventilation costs €6,000 to €18,000 installed in a house (central system) and €4,000 to €8,000 in a flat (decentralised units), including 3% VAT. The Klimabonus pays €60/m² of heated floor area, €70/m² if the approval in principle is requested before 30 June 2027, capped at 50 to 60% of the cost and only with energy advice.
- Installed price: central €6,000-18,000 depending on range and size; decentralised €4,000-8,000 (flat) or €6,000-11,000 (house)
- Klimabonus: €60/m² of energy reference area (€70/m² increased), at most 150 m² per house and 80 m² per flat, and at most 50% of the cost (60% increased): €9,000 (€10,500) maximum
- Conditions: heat recovery ≥ 80%, fans ≤ 0.40 W/(m³/h), airtightness test n50 ≤ 2.0 h⁻¹, 80% of the area ventilated, energy advice mandatory
- Humidity-controlled extract ventilation: €1,500-3,500 up to 120 m², no grant
- Power use: 40 to 60 W for MVHR, against 15 to 35 W for humidity-controlled extract
- Maintenance: filters every 3 to 6 months (€20-60 a set), €120-280 a year in total
A ventilation installer near you
Three ventilation installers established in Luxembourg assess your home and include the grant in their quote. Free, no obligation.
Heat recovery ventilation prices in Luxembourg in 2026
In Luxembourg, heat recovery ventilation costs from €4,000 for a flat with decentralised units to €18,000 for a large house with a high-end central unit, including fitting, ducts, vents and commissioning.
| System | Home | Installed price (incl. 3% VAT) |
|---|---|---|
| Decentralised (room-by-room units) | Flat 60 to 90 m² | €4,000-8,000 |
| Decentralised | House 90 to 150 m² | €6,000-11,000 |
| Central, entry level (70 to 80% recovery) | House 80 to 120 m² | €6,000-10,000 |
| Central, mid-range (80 to 90% recovery) | House 80 to 150 m² | €8,000-13,000 |
| Central, high-end (over 90% recovery) | House 120 to 250 m² | €11,000-18,000 |
Luxembourg market ranges; the breakdown (unit, ducts, vents, labour) and extract-only prices are on our reference page ventilation installation costs. The price rises if the loft is not accessible and false ceilings are needed for the ducts.
The Klimabonus requires at least 80% heat recovery: a unit rated between 70 and 80% does not qualify. Check the certified efficiency on the data sheet before signing.
Klimabonus for heat recovery ventilation: calculation and conditions
The Klimabonus supports heat recovery ventilation with €60/m² of energy reference area (€70/m² if the approval in principle is requested between 1 January 2026 and 30 June 2027), capped at 150 m² for a house and 80 m² for a flat, and at 50% of the cost (60% in the increased period).
1980 house whose façade and roof are insulated in 2026, 140 m² of reference area, mid-range central MVHR. Quote: €10,700 excluding VAT, €11,021 including 3% VAT. Increased flat rate: €70 × 140 m² = €9,800; 60% cap: €6,420 (calculated here on the price excluding VAT). Klimabonus: €6,420. Net cost: €4,601. The mandatory energy advice is itself subsidised (€2,000 increased for a house).
In practice, the percentage cap sets the grant: the maximum flat rate of €10,500 is only reached above €17,500 of works excluding VAT for a 150 m² house. For a 75 m² flat with decentralised units at €6,000 excluding VAT, the grant is €3,600 (60%), below the €5,250 flat rate.
- Technical requirements: heat recovery ≥ 80%, fan power ≤ 0.40 W per m³/h, airtightness test n50 ≤ 2.0 h⁻¹, at least 80% of the reference area ventilated.
- Procedure: only within energy advice with a report, and approval in principle requested before the works.
- Building: more than 10 years since the first building permit; maximum €35,000 per building.
- Extract-only, humidity-controlled ventilation or extractor fans: no grant.
- 3% VAT: ventilation is among the eligible works for a home at least 10 years old used as a main residence.
Ventilation also counts for other grants: new windows are only subsidised if the wall is insulated or ventilation is in place, to prevent condensation. Full scale: grants and the 2026 Klimabonus.
Extract-only or heat recovery ventilation: which to choose?
In an insulated, airtight home, heat recovery is the obvious choice: it recovers heat from the extracted air, filters incoming air, and is the only ventilation that is subsidised; in an older home that is still leaky, humidity-controlled extract ventilation is enough until the insulation is done.
| Criterion | Humidity-controlled extract (type B) | Heat recovery (MVHR) |
|---|---|---|
| Principle | Extraction in wet rooms, fresh air entering through vents in the windows | Extraction and supply through two networks crossing in a heat exchanger |
| Heat recovery | None: air enters at outdoor temperature | 85 to 95% (central), 60 to 80% (decentralised) |
| Filtering of fresh air | None | F7-class filters or better |
| Power use | 15 to 35 W | 40 to 60 W (two fans) |
| Ducts | One extract network | Two networks (extract and supply) |
| Leaky home | Works | Reduced performance: air comes in through the leaks |
| Installed price | €1,500-3,500 (up to 120 m²) | €6,000-18,000 (house) |
| Klimabonus | None | €60/m² (€70/m² increased) |
A 90% heat exchanger turns outdoor air at −3 °C into supply air at about 18 °C when the house is at 20 °C: this is what removes the cold draught from trickle vents.
Which system for which home
| Situation | Recommended choice |
|---|---|
| Whole-house renovation (insulation, windows) or new house | Central MVHR: the home is airtight and the grant applies |
| Old uninsulated house, no insulation planned soon | Humidity-controlled extract type B; MVHR will come with the insulation |
| Insulated house without an accessible loft for ducts | Decentralised MVHR, or central with false ceilings |
| Flat in a co-owned building | Decentralised MVHR if the co-owners allow façade openings, otherwise extract ventilation |
| Allergy or asthma sufferers | MVHR with fine filters: the only system that filters incoming air |
In a very airtight home, extract-only ventilation creates negative pressure that draws air through uncontrolled routes (chimney flue, loft hatch): this is the strongest technical argument for heat recovery after a deep renovation.
Central or decentralised heat recovery ventilation
Central MVHR, with one unit and a duct network, is the most efficient and quietest; decentralised MVHR, with units fitted in the walls of each room, goes in without ducts in an occupied home.
- Central: one unit in the loft, boiler room or plant room, two duct networks, a single machine to maintain. Ideal during a major renovation or when the loft is accessible.
- Decentralised: units often working in pairs, each with a façade opening of about 15 cm, no duct network. Lower recovery and several appliances to maintain; in a co-owned building, façade openings require a vote.
Both qualify for the Klimabonus if they reach 80% recovery and ventilate at least 80% of the area.
Airtightness: the test that decides the grant
For heat recovery ventilation to be subsidised, the house must pass an airtightness test (Blower Door) with a result of n50 ≤ 2.0 h⁻¹, meaning the indoor air volume is replaced no more than twice an hour at a pressure difference of 50 pascals.
An official test costs €300 to €600 excluding VAT for a house. A preliminary test during the works, before the finishes, lets you find and seal leaks (window joints, duct and cable penetrations, hatches) at lower cost. Method and providers: airtightness testing in Luxembourg.
Choosing a ventilation installer in Luxembourg
A good MVHR installer gives you a quote detailing the equipment, air flows, ducts and commissioning, and shows that the Klimabonus requirements are met before you sign.
Business permit and insurance
Business permit number on the quote and professional liability insurance certificate. For the Klimabonus, the installation is part of the file followed by your energy advisor.
Compliant data sheet
Brand and model of the unit, certified recovery ≥ 80%, fan power ≤ 0.40 W per m³/h, noise level, filter class, summer bypass.
Duct network priced separately
Length, diameters, rigid or semi-rigid ducts, insulation of ducts outside the heated volume: an uninsulated duct in a cold loft cancels part of the recovery.
Measured commissioning
Air flows set and measured vent by vent, a copy of the measurement report, and an explanation of filter maintenance.
3% VAT and timing
The 3% rate stated (approval requested by the company before the works) and a commitment to start only after the approval-in-principle request.
Installing heat recovery ventilation in an existing house
In a renovation, installing central MVHR takes 3 to 5 days of work when the loft is accessible, longer if false ceilings must be built for the ducts.
- Energy advice and approval in principle: the advisor includes the ventilation in the renovation concept; the approval request comes before the works.
- Site visit: unit location, duct routes, fresh-air intake and exhaust, wet rooms and living rooms.
- Preliminary airtightness test and sealing of leaks if needed.
- Installation: unit, two duct networks (insulated outside the heated volume), supply vents in living rooms and extract vents in wet rooms.
- Commissioning: flow balancing, final Blower Door test, then the payment request with the « after » energy certificate.
Maintenance and lifespan of heat recovery ventilation
Heat recovery ventilation lasts 15 to 20 years if its filters are changed every 3 to 6 months; allow €120 to €280 a year for maintenance, against €35 to €60 for extract-only ventilation.
- Every 3 to 6 months: filter replacement, €20 to €60 a set. A clogged filter increases fan consumption and reduces air flows.
- Every year: cleaning the heat exchanger and condensate tray, €50 to €150 by a professional.
- About every 3 years: full check of air flows and duct airtightness, €150 to €300.
- In summer: the bypass lets cool night air in without passing through the exchanger; it is not air conditioning.
Regular maintenance conditions the manufacturer’s warranty and the real savings: a dirty heat exchanger can lose much of its efficiency.
Request your heat recovery ventilation quotes
Describe your home (area, floor, accessible loft or not, planned insulation works): we pass your request to three ventilation installers established in Luxembourg, business permit checked. Reply within 48 working hours, free and without obligation; the Klimabonus is calculated in the quote.
Frequently asked questions about heat recovery ventilation in Luxembourg
Do you need ventilation after replacing your windows?
It is not a legal obligation, but the Klimabonus links the two: new windows are only subsidised if the wall is insulated to U ≤ 0.85 W/m²K or ventilation is in place, to prevent condensation. Airtight windows in a house with cold walls and no ventilation raise humidity and lead to mould in the corners.
Can you get the Klimabonus for heat recovery ventilation without energy advice?
No. The ventilation grant only exists within the energy-advice procedure, with a report drawn up before the works and an airtightness test. The advice itself is subsidised: €1,700 for a house, €2,000 if the approval in principle is requested before 30 June 2027.
Do you need the co-owners’ approval for heat recovery ventilation in a flat?
Yes as soon as the installation goes through the façade or affects common parts, which is the case for decentralised units: the general meeting must authorise it by a majority of the votes of all co-owners. The grant is calculated on a maximum of 80 m² for a flat. The co-ownership majorities are detailed on our dedicated page.
How much electricity does heat recovery ventilation use?
Its two fans usually draw 40 to 60 W continuously, or 350 to 525 kWh a year, against 15 to 35 W for humidity-controlled extract ventilation. To be subsidised, the system must not exceed 0.40 W per m³/h of air moved. In a well-insulated house, the heat recovered far exceeds this consumption.
Can the ducts of extract-only ventilation be reused for heat recovery?
Only partly: heat recovery needs a second duct network to supply fresh air to living rooms, which extract-only systems do not have. Extract ducts in good condition can sometimes be reused. When new ducts cannot be run, decentralised heat recovery, with no network, is the solution.
Does heat recovery ventilation cool the house in summer?
A little, thanks to the summer bypass: at night, when outdoor air is cooler, it comes in without passing through the heat exchanger. It is not air conditioning and does not cool the air during the day. Check that the quote includes an automatic bypass.