Installation of an air source heat pump

Appeal Decision Site visit made on 27 August 2025 By G Powys Jones MSc FRTPI an Inspector appointed by the Secretary of State Decision date: 11 September 2025 Appeal Ref: APP/U3935/D/25/3368833 2 Mariner Road, Oakhurst, Swindon, SN25 2LB • The appeal is made under section 78 of the Town and Country Planning Act 1990 (as amended) against a refusal to grant planning permission. • The appeal is made by Mr Henry Chor against the decision of Swindon Borough Council. • The application Ref is S/HOU/25/0523/ADHI. • The development is the installation of an air source heat pump. Decision 1. The appeal is dismissed. Main Issue. 2. This is the effect of installing the air source heat pump (ASHP) on the living conditions of neighbouring residents with reference to noise and disturbance. Reasons 3. The appeal property, a relatively modern linked dwelling, forms part of a large suburban residential estate on the outskirts of the Borough. The house is set on a corner, with its front elevation facing the road. Its side elevation, where the ASHP would be sited, fronts the footway linking Mariner Road with Oakhurst Way. A narrow strip of open space backed by trees sits opposite the side elevation, running alongside the footway. Another house, No.10, is linked to this side elevation. 4. The Council has no objection to the appearance or the siting of the ASHP in design terms, and I have no reason not to share the Council’s views on these matters. 5. Judging from its officer report, the Council is aware of its own and national policies directed to encouraging development such as that proposed in the interests of reducing carbon emissions and sustainability. I too am fully aware of the policies referred to by the appellant. 6. In furtherance of its encouragement, the Government grants planning permission as permitted development (PD) for the installation of ASHPs subject to conditions and limitations, one of which requires the installation to comply with the MCS planning standard (MSC 020). 7. The appellant has produced the sound calculation in accordance with the published tool and has found it to exceed the PD limit. Accordingly formal planning permission is required. The Council, in considering the application, took the view that insufficient information had been provided by the appellant to enable it to properly Appeal Decision APP/U3935/D/25/3368833 2 assess the proposal; in effect, it called for a more comprehensive acoustic assessment. 8. The main thrust of the appellant’s stance is that the submitted MCS calculation shows that the extent to which the PD requirement was exceeded, at less than 2dB, was in his view minimal, and of little consequence in terms of its local effect on noise. Additional, but unnecessary costs would need to be expended in supplying the further information requested. This is seen to act as a discouragement and disincentive to himself and the population generally to install the type of equipment which local and national government policies positively encourage. 9. The appellant produced a document which appears to be the illustrations to a presentation made by Apex Acoustics in respect of ‘Planning for ‘Sound from ASHPs: Reducing the barriers to rollout’. It is suggested therein that MCS 020 consistently predicts higher sound levels, by 5-7dB, and this is relied on by the appellant. 10. I note however that the author of that presentation was party to a recent detailed research paper reproduced in the Proceedings of the Institute of Acoustics: ‘Noise from ASPHs – What do we know?’1 The paper’s conclusions state: ‘From the reviews, surveys and interviews that have been carried out over the past 18 months, there is clear objective evidence that the sound emissions from ASHPs have the potential to cause annoyance and give rise to complaints. The current low level of complaints is very likely to be due to installations occurring under the MCS in low-density areas but this could change as the BUS encourages adoption by households in more suburban and urban areas. The concerns of local authorities and members of the public are justified…’ 11. The MCS standard and the scope of permitted development rights have recently been subject to change. The 42dB limit still stands following these changes, thus begging the question why it was not set higher if one or two decibels here and there make no perceptible difference, as the appellant implies. A limit must be drawn somewhere. 12. Given the site’s suburban location, which I found to be quiet2 during my visit, I intend to adopt a precautionary approach. Whilst this would doubtless be frustrating to the appellant, there is a distinct risk that without the appropriate assessment, as required in the Council’s most relevant development plan policy, neighbours may suffer harmful noise nuisance. The appellant, in my view, is correctly obliged to demonstrate with convincing evidence that they would not. The noise maps produced for the appeal by the appellant are not persuasive, given their unknown or uncertain provenance. 13. I therefore conclude that the information provided in support of the application and appeal is insufficient to demonstrate that the proposal would not cause harm to neighbouring residents’ living conditions by reason of noise and disturbance. Accordingly, the proposal conflicts with that provision of policy DE1 of the Swindon Borough Local Plan which requires all proposals to be assessed for its effects on amenity, in particular, noise and disturbance. 1 Vol.45 Pt 3. 2023 2 Notwithstanding the DEFRA sound map produced – this type of mapping has defined limitations see DEFRA October 2024: ‘Explaining The 2022 Noise Maps’ Appeal Decision APP/U3935/D/25/3368833 3 14. I am also mindful of the guidance provided in the Framework3 which requires decisions to ensure that developments create places with a high standard of amenity for existing and future users. Based on the submitted information I am unconvinced that this objective would be achieved. 15. Accordingly, the appeal is dismissed. G Powys Jones INSPECTOR 3 The National Planning Policy Framework