Appeal 6003533

The appeal is dismissed.

The main issues are the effect of the proposed development on the:  character and appearance of the area and  living conditions of neighbouring occupiers with particular regard to noise and disturbance

The site comprises a mid-terrace three-storey house with a small open front garden and a larger enclosed rear garden within a gated development of similar houses set around common landscape, parking and circulation areas, much of which are formed by hard surfaces in the vicinity of the proposal.

The proposal is to install an air source heat pump (ASHP) of 1375mm height, 855mm width and 595mm depth in a position about 250mm from the front of the house, roughly central to the house frontage with the top partially in front of a window. This would be about 0.7m from the pavement to a common area.

Whilst the application form indicates that no external materials would be used, the drawings show that the ASHP would be dark grey and that the top would be curved and contain a grille near the front that would conceal a fan with a 500mm diameter and a maximum speed of 970 revolutions per minute.

On my site visit I saw that there were bins, waste caddies, plant pots, shrubs and small trees in front gardens nearby and telecoms equipment cabinets and salt grit bins on a footway, but no fixed objects or plant of a size, shape or appearance like that proposed within open front gardens or common areas.

The curved lines and dark shade of the ASHP would soften its appearance, but it would nonetheless appear unusual in its context and be visible to most residents of and visitors to the development. The extent to which it would fail to respect the existing dwelling is not minimised by a lack of heritage constraints.

ASHPs may well become a common sight in residential contexts, but they will vary in design and location, not least to minimise visual impact. The appellant states that there are no other viable locations for it, but no technical explanation is given as to why, for example, it could not be located in the rear garden.

Overall, I am satisfied that the proposal would harm the character and appearance of the area, contrary to Policy 28 of the Sutton Local Plan 2018 (SLP).

The application was submitted with a simple noise assessment resulting from the completion of a standard calculator spreadsheet provided by the [name] (MCS). This calculated the sound pressure level one metre from the centre of the closest habitable room as 37.2dB, which resulted in a ‘fail’.

Whilst the calculator output does not indicate above what sound pressure level a ‘fail’ would result, the appellant states that the limit is 37dB, which I accept that the result would only marginally exceed. However, as the Council’s environmental health officer points out, this is based on a standardised noise environment.

Further evidence was supplied at appeal, including road noise modelling maps by the Department for Environment, Food & [name]. This predicted an ambient road noise baseline of 45-50dB LAeq, 16h for the site, against which the appellant argues that the source, being within 10dB, would be indistinguishable.

However, as the Council’s environmental health officer advises, this modelling is based on distances from traffic flows and road types. I am not convinced that it adequately accounts for intervening structures. In this case, surrounding buildings are three storeys high and largely enclose the affected space.

The location on a cul-de-sac creates potential for limited activity and background noise, particularly in late evenings and at night. Whilst the calculator accounts for barriers and enclosure in a simple way, there is a high proportion of hard surface in the vicinity of the proposal from which noise could reflect.

In this context and without an environmental noise survey, I cannot be sure the periodic starting, stopping and running of the ASHP would not cause a nuisance. Furthermore, I am confident that it would be a nuisance to residents and visitors parking or walking past it on the pavement alongside.

I conclude that the proposal would harm the living conditions of neighbouring occupiers with regard to noise and disturbance, contrary to SLP Policy 29.

It is the policy of the Secretary of State that the need to mitigate climate change should be considered in assessing planning applications1. The need is indeed urgent, but I am not convinced that mitigation could not be achieved in this case without the harm to character, appearance and living conditions identified. 1 National Planning Policy Framework paragraph 163.

For the reasons given above the appeal should be dismissed.