EcoDesign and Class 5: how to lock down your permit file in Luxembourg

What does EcoDesign 2015/1189 really change on a new build?

EU Regulation 2015/1189 has set the minimum thresholds for any biomass boiler placed on the European market since 2020. It covers seasonal efficiency, CO, NOx and particulate emissions, and requires an official technical check before commissioning.

For a new build in Luxembourg, it is the first supporting document for the permit: without EcoDesign, the boiler can be refused or become ineligible for aid.

EN 303-5 Class 5: why has it become the benchmark?

EN 303-5 ranks solid-fuel boilers from 1 to 5, with Class 5 being the strictest (efficiency and emissions). All serious manufacturers — including Tatano — now target Class 5 for their pellet models.

Requesting the EN 303-5 Class 5 certificate in the specifications is the simplest way to ensure the equipment meets or exceeds EcoDesign.

Biomass vs fossil carbon footprint: how big is the gap?

According to ADEME, a pellet boiler has an emission factor of about 0.027 kgCO₂e/kWh useful, versus 0.265 kgCO₂e/kWh for fuel oil and 0.205 kgCO₂e/kWh for natural gas.

For a 120 m² new build consuming 60 kWh/m²/year (BBC), that's roughly 200 kgCO₂e/year on biomass versus 1,900 kgCO₂e/year on oil — about 9× less. This gap directly drives the building's energy label and therefore its resale value.

How to integrate compliance from APS to capture Klimabonus?

From the sketch design stage (APS), three reflexes lock down compliance and subsidy:

Architects who tick these boxes from APS turn a regulatory burden into a commercial asset for the project owner.

• Insist on EcoDesign + EN 303-5 Class 5 as a firm contractual requirement.
• Plan a pellet silo (pneumatic delivery) and a 500–1,000 L buffer tank to unlock the +15% bonus.
• Run the Klima-Agence aid simulator and check the cumulative bonus with municipal grants (variable by commune).
• In Luxembourg, only pellet boilers qualify for Klimabonus 2026: up to €8,000 for a single-family home, €6,000/unit in multi-family (cap €40,000), €6,000 for a heating network (cap €24,000).