Installation of air source heat pump to rear of property

Appeal Decision Site visit made on 29 May 2025 by Eleni Marshall BSc (hons) MSc FRICS FAAV MRTPI an Inspector appointed by the Secretary of State Decision date: 06 June 2025 Appeal Ref: APP/P0119/D/25/3363944 65 Long Leaze Road, Patchway, South Gloucestershire, BS34 5GR • The appeal is made under section 78 of the Town and Country Planning Act 1990 against a refusal to grant planning permission. • The appeal is made by Venkata Satish Karna against the decision of South Gloucestershire Council. • The application reference is P25/00323/HH. • The development proposed is installation of air source heat pump to rear of property. Decision 1. The appeal is dismissed. Main Issue 2. The main issue is the impact of the proposal neighbouring residential amenity. Reasons 3. The appeal site is a semi-detached residential dwelling which is located in a residential area accessed from Long Leaze Road. The proposal before me seeks permission for the installation of an Air Source Heat Pump (ASHP) to the rear of the property. There appears to be a discrepancy between the submitted plans in so far as the site plan shows the AHSP to be in the region of two metres from the shared boundary, however, the proposed elevations show the ASHP beneath a window on the host dwelling in the region of a metre from the boundary of the appeal site which is shared with 67 Long Leaze Road (no. 67). 4. Despite this I note the position of the proposal in the context of the appellant’s other documentation, and it would appear that the proposal would be intended to be located as per the submitted site plan, not as per the elevational drawing under the window. In any case I find that the proposal would be located in relatively close proximity to the shared boundary with the pair of semi-detached dwellings effectively being a mirror image of each other in terms of their fenestration and rear amenity space. ASHP’s can produce a persistent background noise and low frequency hums, even at low decibels, which can lead to disturbance and general noise complaints from the occupants of adjacent residential dwellings if not appropriate for the site context and/or any impacts are appropriately mitigated. 5. The MSC Assessment shows a fail in relation to noise. No information, within the original application documents, has been provided to suggest that the ASHP would be covered or concealed within a casing unit and therefore the Council have based their decision upon the assumption that the ASHP would be installed and appear as shown in the submitted specifications and plans. I have no evidence before me to consider the proposal differently and have proceeded on the basis of the same Appeal Decision APP/P0119/D/25/3363944 2 assumption. The appellant states that the noise level is marginally above permitted development levels, however, the fact that it is above permitted development levels means that the proposal has (whether this is marginally or not) exceeded the noise level above which a formal assessment as to the impact is required in order to protect neighbouring amenity as part of an application for planning permission. 6. Furthermore, in this case, I note that Environmental Protection outline, as a statutory consultee, state that they consider the background noise level at the appeal site would be notably less than that utilised within the standard MSC Assessment. At the time of my site visit I found the appeal site, and its immediate setting, to be very quiet with limited background noise which I find to be consistent with the consultee assumption. Whilst my site visit is only a snapshot in time, I find that there is sufficient reasoning, based upon the evidence available, to consider that the actual background noise levels for this site reasonably need to be taken into account, as a starting point, in order to correctly assess the actual impact of the proposal in the context of the appeal site and neighbouring residential properties. 7. The failure of the proposal in the context of the MSC Assessment could, reasonably, have prompted the appellant to consider mitigation measures to demonstrate that there would be no inappropriate impact to residential amenity as part of the submitted application. The proposed location, and layout, of the host property and the adjacent dwellings in an area which I found to be quiet in terms of background noise, and which was noted as potentially experiencing lower levels of background noise by Environmental Protection, means that I find there is strong potential in the absence of evidence to the contrary for noise associated with the proposed ASHP as submitted to result in unacceptable impact. 8. I acknowledge that neighbouring properties are likely to benefit from double glazing, however, I do not find that this itself can be relied upon as a form of mitigation. I would expect occupants to have windows open and/or sit out within their garden where the proposal for noise could have its greatest impact. Given that the acceptability of the proposals would be entirely based upon their ability to be compatible with neighbouring residential amenity I find that such detail should be considered, prior to determination and in that regard, it would be inappropriate in this case to secure such details by condition. I do not find that the Council are resistant to the provision of such equipment but that they are, reasonably, requesting further information to ensure that the installation is appropriate for the context of the appeal site on a case-by-case basis in relation to amenity. 9. Residential areas in South Gloucestershire may well be subject to background noise (traffic and neighbouring properties as outlined by the appellant) but as outlined, I found the site to be very quiet during the time of my site visit with limited background noise of any note. In such cases an appropriately assessed noise assessment would take into account any background noise in considering whether the proposal would have any unacceptable impacts in relation to neighbouring residential amenity. 10. The submission before me fails to provide a noise assessment or propose appropriate mitigation measures to ensure/demonstrate that the proposal would not result in unacceptable impact. I acknowledge that the proposal would be fitted with anti-vibration feet and comment is made as to the recognised standard differences for the average individual to perceive a change in volume, but this statement is not Appeal Decision APP/P0119/D/25/3363944 3 evidenced nor verified, and I find that it would be inappropriate of me to rely upon this without supporting information or referencing to qualify the statement made. 11. I acknowledge South Gloucestershire’s Climate Action Goals, as well as the support within the National Planning Policy Framework 2024 (the Framework) for the provision of renewable and low carbon energy and heat. I also acknowledge support and the weight that needs to be given to energy efficiency and low carbon heating improvements to existing buildings both domestic and non-domestic (through installation of heat pumps where these do not already benefit from permitted development rights). I do not, therefore, challenge the general level of policy support for such installations but equally, whilst the Framework is supportive of energy efficiency and low carbon heating, it is also clear that planning decisions should also ensure developments create places with a high standard of amenity for existing and future users. Whilst reducing carbon emissions is a high priority at both national and local level (at that ASHPs can play a critical role in achieving this) I do not find that this overrides the need to appropriately consider the impacts. 12. Overall, I acknowledge the supporting evidence provided by the appellant including the noise map showing the receiver points and existing windows, however, given the potential for such standardised calculations to not take into account what I consider to be potentially lower background noise levels at this site, the proximity of the proposal to the neighbouring property’s garden, windows and provision of only a timber boundary fence, I find that there is insufficient evidence before me in the context of this appeal to be certain that if the proposal was allowed it would not result in unacceptable impact to the residential amenity of no. 67. I am also mindful that the absence of evidence to the contrary the presence of a boundary fence actually has the potential to amplify noise. The provision of an appropriate noise impact assessment and/or appropriate mitigations would enable proper assessment of the proposal and demonstrate whether the proposal would be appropriate taking into account the site characteristics as set out by the appellant. 13. Based on the density of the surrounding development, and the information provided to date, the proposal should include mitigation recommendations and specification to be considered as part of the proposals in order to protect the amenity of local receptors in this case. This approach is further supported by the professional advice note prepared by The Chartered Institute in Environmental Health and the Institute of Acoustics, as noted by the Council, which confirms that where planning application will be necessary a noise assessment should be provided which is proportionate and take into account the local circumstances and nature of the installation. I, like the council, afford this advice limited weight (as it is not policy) but it is indicative of a general acceptance, and reasonable approach, that a proportionate assessment should be undertaken to ensure proposals of this nature are appropriately assessed in the context of residential amenity notwithstanding the environmental benefits of such proposals as outlined by the appellant 14. In the absence of such information, I find there is sufficient reason to uphold the refusal and dismiss the appeal. There is insufficient information and evidence to demonstrate that the proposal would not result in detrimental impact upon the living conditions/amenity of neighbouring occupiers and the proposal would therefore be contrary to South Gloucestershire Local Plan Policies, Site and Places Plan 2017 Policy PSP8 which seeks to avoid unacceptable impact on the residential amenity of occupiers with regard to noise or disturbance and Policy PSP38 which supports Appeal Decision APP/P0119/D/25/3363944 4 development within existing residential curtilages where it would not prejudice the amenities of neighbours. Other Matters 15. I note it is outlined, by the appellant, that similar installations have been approved locally. A list of three application references is provided, with no commentary and further information such as the site context, the system to be installed nor the decision/council’s reasoning for me to understand why the decisions have been made to approve such examples on their own merits to enable me to give them weight within this appeal. Based upon the information provided I have no indication, for example, whether the noise levels were considered appropriate due to the proximity (or lack of) to neighbouring properties, the outcome of the MCS Assessments or whether the Council felt there were other factors which could be overcome in order to allow those proposals which are stated to have been approved, to be approved. Conclusion 16. For the reasons outlined above, and taking into account all other matters raised, I conclude that the appeal should be dismissed. Eleni Marshall INSPECTOR