Permitted development rights update for air source heat pumps

Announced by the Ministry of Housing, Communities and Local Government (MHCLG) last November, changes to permitted development rights for air source heat pumps (ASHP) in England came into force on 29th May 2025.

As one of the key technologies expected to help decarbonise heating in the UK,
industry and government have been collaborating to help identify and resolve barriers to deployment of heat pumps. This important step will make heat pump installations simpler, cutting red tape in the vast majority of situations.

Relevant legislation has been made in The Town and Country Planning (General
Permitted Development) (England) (Amendment) Order 2025. Key changes which will now fall under permitted development include:

• ASHP can be installed within 1m of a property boundary
• The size limit of the ASHP has increased from 0.6m³ to 1.5m³ for dwellings
• Two ASHPs are permitted for detached dwellings
• ASHPs can also be used for cooling, meaning air-air heat pumps can now also benefit from PDR.

The legislation makes reference to the recently updated Microgeneration Certification Scheme Planning Standard (MCS 020 a) for the Air Source Heat Pump Sound Calculation.

Different arrangements remain in place in the other devolved administrations, although it is noteworthy that the Welsh government are currently consulting upon similar changes which we hope will be bought into effect as soon as possible.

Commenting on these changes Jeff House, Director of External Affairs and Policy at
Baxi, stated: “This is a good positive step and something we have been pushing for
through the Heat Pump Association for some time. As we look forward to the unveiling of the Warm Homes Plan we hope that other barriers to heat pump deployment, such as the spark gap, are addressed in short order”.

Find out more about the Baxi Air Source Heat Pump range and new Baxi ASHP Pre-
plumbed Cylinder here.