The Heating and Hotwater Industry Council (HHIC) published its response on 3 April 2024 to the Department for Levelling Up, Housing and Communities consultation on changes to various permitted development rights1. The body, which describes itself as the leading representative body for the UK domestic heating and hot water industry, worth £3-4 billion per year, and says its membership covers approximately 94 per cent of heating and hot water solutions available in the UK, answered questions on air source heat pump siting, size and noise1.
On the one metre boundary rule, HHIC opposed removal as proposed. It said the rule should be replaced rather than scrapped, arguing that the requirement fails to ensure the positioning of a heat pump has taken into account the effect on the neighbouring property or the manufacturer's installation instructions1.
"HHIC does not believe that the 1 metre rule makes any sense and should be replaced as this requirement fails to ensure that the positioning of the heat pump has taken into consideration the effect on the neighbouring property or the manufacturers installation instructions."
On the 0.6 cubic metre volume limit, HHIC said the maximum size rule should be removed, apart from requirements it wants retained. It said a larger unit could allow slower running fans and larger evaporators to reduce noise, but that system design and performance should reflect the use of a larger heat pump1. It listed two limitations it wants kept: properties in a designated conservation area, a World Heritage Site, or listed buildings and scheduled monuments still require planning consent, and generally only one air source heat pump is permitted per property, so homes needing more than one must seek planning permission1.
On noise, HHIC said it would strongly argue against increasing the background noise assumption above 40dB, noting that sound levels can be as low as 18-20db(A) in very rural areas, especially at night, and that rural and urban areas ought not to be treated the same in any installation standard1. It said heat pumps should have mandatory annual service, to keep units in good working condition and minimise potential increases in noise as they age1.
HHIC also called for a national installation standard for heat pump systems drafted and maintained by the British Standards Institute (BSI), and for hybrid systems consisting of an air source heat pump and gas boiler to be added to future policy, legislation and a national installation standard1. It asked Government to support the Benchmark scheme, saying the Benchmark checklist is a means of meeting the commissioning requirements within part L of the Building Regulations and the service record helps maintain installation standards and noise requirements1. It recommended a review of part G3 of the Building Regulations, which it believes is out of date, and suggested expanding the EPC system to include building details as an Energy Performance and Buildings Certificate1.
On multiple installations, HHIC said detached dwellinghouses should be permitted a maximum of two air source heat pumps only if planning permission is sought, as the assessment and implications are more complex, and that stand-alone blocks of flats should be permitted more than one only if planning permission is sought, with the planning rules also reviewed1. It said the increase in noise in towns, especially for those living next to a block of flats where a large number of units will be installed, has to be controlled by building regulations1.
Why it matters for households
The rules under discussion decide whether a householder needs planning permission before an air source heat pump can be installed, and where on the property it can go. The one metre boundary rule and the 0.6 cubic metre size limit are the two constraints HHIC addressed directly, and its position is that neither should simply disappear without replacement safeguards1. For a home, the boundary rule shapes how close a unit can sit to a neighbour's land, and the size limit shapes which models can go in without an application. HHIC's argument is that removing the size limit could allow quieter-running larger units, while removing the boundary rule without a replacement could push noise towards neighbours1. Its call for a BSI national installation standard, mandatory annual servicing and hybrid system coverage points to a framework in which installation quality, rather than the planning exemption alone, carries the noise and performance requirements1. Households in conservation areas, World Heritage Sites, listed buildings and scheduled monuments would still need consent under the limitations HHIC wants retained1.
What happens next
The consultation response was published on 3 April 20241. No date for the Government's decision on the permitted development changes has been reported.
Sources1 cited
- 661812F1097C7.pdf, hhic.org.uk