Appeal 3284671

The appeal is dismissed.

The application is described as part retrospective. It is clear from my site visit and the evidence before me that the air conditioning unit has been constructed, but the wall mounted acoustic sound reduction enclosure has not. Accordingly, I have determined the appeal on this basis.

The main issues in the appeal are the effect of the proposals on: • the character and appearance of the host house and the streetscene. • the living conditions of the occupiers of No.[address], with particular regard outlook and noise.

No. [site address] is a detached two-storey house of a contemporary style. The existing Air Conditioning Unit (ACU) is positioned on the right hand flank elevation of No.5 at a reasonably high level (around 3.2m) but toward the back of the house. It is of fairly modest proportions (0.9m x 0.9m x 0.5m) but is set off the flank elevation by a support bracket fixed to the wall. No.5 and its neighbour at No.[address] are very set close to their respective boundaries such that the gap between the two flank elevations is only just over 1m. The ACU is most readily seen when directly facing this gap from the street (above the side gate of No.5), but the close proximity of the flank elevations of the two houses and the set back means that the zone of visibility is actually very limited. I saw on my site visit that the ACU unit can be seen from the footway on either side of [address] but it is barely visible, and only for a short section as you walk in either direction. Views between No.5 and No.7 (and therefore the ACU) are also reduced by an existing tree within the footway. Whilst appearing somewhat utilitarian or commercial, the ACU would not be at all prominent in the streetscene and does not appear a particularly incongruous addition to the host house.

The proposal is for a wall mounted acoustic reduction enclosure that would encase the existing ACU. This would increase the overall depth of the unit by around 150mm and height by around 300mm. Despite this modest increase in size, I am satisfied that the proposal would not substantively detract from the character and appearance of the host house and surrounding area.

Consequently, on this main issue, I find no conflict with Policies SS1 and UD1 of the Watford Local Plan Part 1 – [name] 2006-31 (2013) (CS) which, amongst other things, seek to ensure high quality design that reflects local character.

The rear elevation of No.5 extends beyond that of its neighbour at No.[address] (No.7) and the location of the ACU to the rear of the property means that it is visible from the rear windows of No.7. This is confirmed in the [name] (AR) submitted on behalf of the appellant which describes the relationship in the following terms ‘the nearest non-associated residential window being rear aspect first-floor windows of [address], 2m from and with line of sight of the ACU next door at [site address] .’ Whilst the proposed louvred plant enclosure would improve the fairly commercial appearance of the ACU, it would increase its overall proportions and therein prominence when viewed from the rear of No.7, causing harm to outlook.

I recognise that the existing ACU has been in its current position for a number of years and note the appellant’s comments that there has been no noise or disturbance or detriment to the amenities of surrounding residential properties to date. However, I am mindful that the absence of an objection, or objections, does not in itself confirm that there is no harm to the living conditions of neighbours arising from a development.

The AR submitted with the planning application assessed the proposal against accepted [name] (BS) 4142 whereby the noise from a source is compared with the prevailing background noise. At a distance of 1m from the nearest noise sensitive window (the rear first-floor window of No.[address], only 2m away) the ACU noise was measured as being +24dBA above background levels. The appellant’s own AR concluded that the ACU ‘will therefore require significant noise attenuation in order to comply with the [name] and reduce the impact on neighbour amenity.’ I accept that the assessed increase (of +24dBA) represents a ‘worst case scenario’ based on the lowest background noise level. However, even if the average background noise level were to be taken, the increase would still be +18dBA. BS 4142 gives an indication of the impact of an increase in noise – a +10dBA increase represents a ‘significant adverse impact.’

It is proposed to retain the existing ACU in its current position, but to enclose it with 150mm deep single bank acoustic louvres on three sides. I note that the advice in the AR is that it is unlikely that there is sufficient space in the current location (between No.5 and No.7) for the ACU unit to be re-housed in an enclosure capable of attenuating noise levels at or below background levels. Moreover, it advises that a minimum 300mm is typically required around the ACU to allow sufficient airflow and efficient operation. The acoustic enclosure detail submitted with the planning application (ref. 21059-PL-02-P2) shows only 50mm between the ACU and the acoustic louvres. So, well below this minimum. The AR assesses the effect of the proposed plant enclosure on noise levels. This shows that although there would be a reduction in noise associated with the ACU, it would still be +16dBA above the lowest background noise level. I therefore find that notwithstanding the proposed enclosure, the ACU would still have a significant adverse noise impact, such that it would cause harm to the living conditions of the neighbours at No.7.

The proposal would therefore fail to accord with CS policy SS1 in so far as it seeks to secure well-designed development with regard to the amenity of neighbouring residents. It would further fail to accord with saved Policy SE22 of the Watford District Plan 2000 (2003) which seeks to ensure the separation of noise sensitive uses from sources of noise.

I have noted the appellant’s comments regarding the clarity of information available for homeowners in relation to the installation of ACUs and whether planning permission is required, but this is beyond my consideration of the planning merits of the proposal before me.

Notwithstanding my conclusions with regard to character and appearance, I have found significant harm to the living conditions of the neighbours of No.[address] with regard outlook and noise. Therefore, for the reasons given above, the appeal is dismissed.