clearSkies certified appliances meet the minimum performance level for Ecodesign Regulations – the minimum legal requirement for an appliance manufactured in the UK from 1st January 2022.

Check out the helpful clearSkies explainer video here.

Efficiency & emissions criteria

The Ecodesign Regulations cover specific minimum criteria that an appliance must achieve under set test conditions, which are independently run.

These criteria are the minimum energy efficiency of the appliance and the maximum levels of emissions permitted of:

These new Ecodesign Regulations represent a significant tightening of these criteria over the current CE requirements.

You can read more about the types of emissions covered under Ecodesign here.

Defra Exemption

In addition to meeting the requirements of Ecodesign for efficiency and emissions, all clearSkies certified appliances at Level 3 or above will also have been verified by the scheme administrator as meeting the requirements for Defra Exemption.

Defra Exemption is where an appliance’s emissions have been independently tested and are low enough that Defra has granted exemption to allow the appliance to be burnt with wood in a Smoke Control Area.

All Level 3 and above appliances certified under the clearSkies scheme have been verified by the clearSkies Administrator, Kiwa Ltd, as complying with both the Ecodesign efficiency and emissions performance requirements, and Defra Exemption and as having the appropriate independent test certificates in place to confirm this.

clearSkies Levels explained

A clearSkies label on a wood burning appliance means you can be assured that the appliance you are buying meets all the energy and efficiency criteria, and the different levels allow you to identify how far beyond Ecodesign criteria they go in terms of reducing emissions and increasing efficiency. This is set out in the different levels of clearSkies certification which are:

Ecodesign compliance

Furthermore, all manufacturers with appliances certified under the clearSkies scheme have had all their emission and efficiency performance data in respect of their Ecodesign compliance and CE mark verified, and the manufacturers have self-certified to clearSkies that they have complied with all other aspects of Ecodesign and CE mark compliance.

Please note: Defra Exemption is granted by each individual country in the UK, and you therefore need to ensure that exemption is in place for the country where you are installing the appliance if you are installing it in a Smoke Control Area. The clearSkies product listing shows the specific countries where the appliance is Defra Exempt

Mineral fuel appliances

clearSkies also covers mineral fuel appliances. Mineral fuels are energy dense and well-known to older generations for their convenience and heat output, however they are mainly fossil fuels and have declined rapidly in popularity due to the growing preference for low carbon wood fuels.

The category of Mineral fuels includes approved Manufactured Smokeless Fuels (MSF) which are engineered composite blends of various types of solid fuel. They can and do include biomass elements and much lower carbon blended fuels are available for Mineral fuel appliances.

While these appliances don’t qualify for a clearSkies Level (because these levels are designed to promote clean wood burning) and would not be listed as Defra Exempt within the clearSkies product listing, they can still qualify for the clearSkies Mark upon satisfying the energy efficiency and emission levels criteria pertaining to the Ecodesign Regulations as set out above.

Smokeless mineral fuels can be burnt in a smoke controlled area. The appliance does not require Defra exemption for them as an approved fuel itself is exempt for use in these areas.

A mineral fuel appliance certified under the clearSkies scheme will receive the following mark:


Full details of the Scheme, including emissions and efficiency criteria, can be found in the Scheme Rules.