The Welsh Ministers have approved amendments to Approved Document J, the practical guidance supporting Part J of Schedule 1 to the Building Regulations 2010, covering combustion appliances and fuel storage systems. The approval and publication of the amendments were announced in circular WGC 004/2024, issued on 4 October 2024 by Mark Tambini, Head of Building Regulations Policy1.
The amended document now includes guidance that where a new or replacement fixed flued combustion appliance of any fuel type is installed in a dwelling, a carbon monoxide alarm should be provided. The fuels named are oil, gas (including LPG) and solid fuel, and the guidance covers fixed flued cookers as well as heating appliances1. The new provisions sit at paragraphs 1.24 to 1.30 in Section 1 of the document. Paragraphs 2.34 to 2.36 of the previous edition, which dealt with carbon monoxide alarms for appliances burning solid fuel only, have been omitted as a result1.
The circular sets out where alarms should be provided: in every space, including connected spaces such as attached garages and loft spaces, containing a fixed combustion appliance, including a fixed flued appliance used for cooking; and in high-risk accommodation, that is a bedroom or principal habitable room such as a living room, where a flue serving a combustion appliance passes through those rooms1. Alarms should comply with BS EN 50291-1:2018, include an integral sounder and be powered by a battery designed to operate for the working life of the alarm, with a warning device to alert users when that working life is due to pass. Guidance on installation is available in BS EN 50292:2023 and from manufacturers' instructions1.
"In accordance with section 6 of the Building Act 1984, the Welsh Ministers have approved the amendments."
The circular also records minor changes correcting a statutory instrument number and an extract from paragraph J3 of Schedule 11. The Welsh Ministers consulted the Building Regulations Advisory Committee for Wales before approving the amendments1.
Why it matters for households
Carbon monoxide is produced by combustion appliances and cannot be seen, tasted or smelled, which is why alarm provision is dealt with in building guidance rather than left to occupants to judge. The change widens the fuel types covered by the alarm guidance in Wales: previously the relevant paragraphs addressed solid fuel only, whereas the amended document applies to oil, gas including LPG, and solid fuel, and to fixed flued cookers as well as other appliances1. For a household in Wales having a new or replacement fixed flued appliance installed, the guidance that applies to that work now expects an alarm in the space containing the appliance, and in certain rooms a flue passes through. The document also sets out what an alarm should be: compliant with BS EN 50291-1:2018, with an integral sounder and a battery lasting the working life of the unit1. Further detail on placement is covered in guidance on where a carbon monoxide detector should be fitted, and the wider safety context is set out in carbon monoxide and home heating safety. The change forms part of the building standards that apply in Wales, which are distinct from those in England and are described in energy and buildings policy in Wales.
What happens next
The changes come into force on 6 January 2025, and the approval takes effect on the same date, except in respect of work already commenced before that date1. The withdrawal of approval of the previous edition also takes effect on 6 January 2025, except in respect of work already commenced before that date1. The 2010 edition incorporating further 2010 amendments continues to apply to building work where the work has commenced before 6 January 2025; or where a building notice, initial notice or amendment notice has been given to a local authority and not rejected, or full plans have been deposited, before that date, provided work commences within three months beginning on 6 January 2025; or where no notification is required and the work commences within three months beginning on 6 January 20251.