The 1m boundary planning rule for ASHPs scrapped from 29/05/2025 in England and Wales

NedS

The government has passed legislation that comes into force on 29/5/2025 that amends existing legislation, removing the 1m boundary requirement for permitted development in England and Wales:

https://www.legislation.gov.uk/uksi/2025/560/introduction/made

The relevant part is Part 5 (3)(c), which states:

https://www.legislation.gov.uk/uksi/2025/560/article/5/made

(c)omit sub-paragraph (e).

The now omitted sub-paragraph (e) is G.2(e) which previously stated:

https://www.legislation.gov.uk/uksi/2015/596/schedule/2

G.2  Development is not permitted by Class G if—

...

(e)any part of the air source heat pump would be installed within 1 metre of the boundary of the curtilage of the dwellinghouse or block of flats;

This is great news for anyone wishing to install an ASHP to the side of their property which may not have had 1m clearance to the boundary this preventing siting of the heat pump.

NedS

I will be seeking to move my heat pump to a better location after the end of this month, as it's currently sat in the middle of my patio (1m from boundary) whereas now I can re-site it closer to the boundary wall, allowing for suitable air circulation behind.

subjecttocontract

Might it not be such good news for neighbours ?

NedS

subjecttocontract said:

Might it not be such good news for neighbours ?

The noise requirements are unchanged and must still be met as part of Permitted Development. As most heat pumps require at least a foot of space behind for adequate air circulation, you are probably talking about placing it 2 foot closer to the boundary at 1 foot rather than 1 metre.

I'd be very surprised if moving it that small distance closer to the neighbour's boundary is going to make a material difference to the overall noise levels they experience. In my experience, my heap pump makes less noise than my neighbours oil boiler flue, and certainly makes less noise than the oil boiler it replaced. There are currently no specific noise constraints placed on the noise emitted by a gas or oil boiler.

QrizB

There are also some other changes to permitted development of heat pumps in those new Regs, I see. One of them might allow heat pumps that can cool as well as heat? Need to look on a proper screen and not my phone so I can compare side-by-side!

NedS

QrizB said:

There are also some other changes to permitted development of heat pumps in those new Regs, I see. One of them might allow heat pumps that can cool as well as heat? Need to look on a proper screen and not my phone so I can compare side-by-side!

Correct,

(a)the air source heat pump is used solely for heating purposes;

becomes:

(aa)the air source heat pump is not solely used for the purpose of cooling;

so cooling is now permitted, as long as the heat pump also provides heat.

Alnat1

Do you still need planning for more than 1 heat pump? It was previously mentioned that this might change.

barker77

Oh wow so is air to air now included in the grant ?! 

NedS

Alnat1 said:

Do you still need planning for more than 1 heat pump? It was previously mentioned that this might change.

Two are now permitted for detached dwellings. Not permitted if:

(i)more than one air source heat pump on, or within the curtilage of—

(aa)a dwellinghouse which is not a detached dwellinghouse;

(bb)a block of flats;

(ii)more than two air source heat pumps on, or within the curtilage of, a detached dwellinghouse;”;

wrf12345

Are you allowed to have a heat pump at the front or does it have to be sides and/or back? Good updates to the rules, though.

QrizB

barker77 said:

Oh wow so is air to air now included in the grant ?! 

These changes are about permitted development for planning permission purposes. No change to the BUS grant.