Appeal 3334757

The appeal is allowed and planning permission is granted for the erection of a single storey rear extension with roof windows, raising of roof height including the addition of roof windows, rear glazed gable and repositioning of PV panels; alterations to external openings, replacement of bay window to front elevation, partial rendering to front and side elevations; and garage conversion and alterations to existing driveway at [site address] , Harpenden, Hertfordshire [postcode] in accordance with the terms of the application, Ref 5/23/1026, dated 12 May 2023, subject to the following conditions:

The development hereby permitted shall begin not later than 3 years from the date of this decision.

The development hereby permitted shall be carried out in accordance with the following approved plans: Site Location Plan; 1362.01.01; 1362.01.02; 1362.01.03; 1362.01.04; 1362.01.05; 1362.02.01 [name]; 1362.02.02 [name]; 1362.02.03 [name]; 1362.02.04 [name]; 1362.02.05 [name]; 1362.02.06 [name] and 1362.02.07 [name].

The materials to be used in the construction of the external surfaces of the development hereby permitted shall match those used in the existing building unless otherwise specified on the approved drawings.

The windows within the south west elevation of the property and the development hereby permitted shall be fitted with obscured glazing, and no part of those windows that is less than 1.7 metres above the floor of the room in which it is installed shall be capable of being opened. Once installed the obscured glazing shall be retained thereafter.

The amendments of the National Planning Policy Framework (the Framework) were published in December 2023 after the determination of the appeal application. These amendments do not alter the basis upon which this appeal has been assessed.

It is considered that the main issue is the effect of the proposed development on the living conditions of the occupiers of neighbouring properties.

The appeal property is a 2-storey detached dwelling situated within a primarily residential area. The proposed development includes a single storey extension to the rear of the property, together with a roof extension to increase the ridge height and the creation of a gable projection within the enlarged rooflope. The single storey extension would have a depth of about 4.1 metres which exceeds the 3 metres cited in Policy 72 of the [site address] District Local Plan Review (LP) as the normal maximum for such additions. This policy does not preclude longer extensions and the appellants have identified that a 4 metre long rear extension could be erected as permitted development and this is a material consideration to which significant weight is given as a fallback position. However, the proposed extension exceeds this limitation by about 0.1 metres.

The appellants have identified that an 8 metre long single storey extension could, subject to the prior approval process, be erected to the rear of the property but no details of what could be erected have been provided. Similarly, although reference is made to potential permitted development rights to increase the height of dwellings no details about what could be undertaken have been provided. Accordingly, in the absence of such information this appeal scheme has been assessed on its own circumstances.

By reason of siting further away from the footway of [address], the 2-storey side elevation of the property already projects for about 5.6 metres along the shared boundary when measured from the original rear elevation of [address]. With the erection of the proposed rear extension, there would be a 2-storey/single storey wall sited close to the shared boundary and projecting around 9.8 metres from the original rear elevation of No. 140. This neighbouring property has an extensive rear garden.

However, No. 140 has been altered by the addition of a single storey rear addition and its rear wall is similar to the siting of the property’s rear elevation. Within the rear elevation of this addition are the extensive openings for the living room of No. 140. There are only secondary side windows which face towards the appeal property. An original ground floor window within the rear elevation of No. 140 is shown on sales particulars dating from 2023 to serve a lobby rather than a habitable room. The lobby is shown to provide a link between the kitchen and a utility room. The study for No. 140 referenced by the Council is indicated to be at the front of this dwelling.

Although the proposed rear extension would project 4.1 metres from the current rear elevation of the property, as already identified the difference in depth would only be 0.1 metres when compared to what could be erected as permitted development. Further, because of the type of room served by the original rear window of No. 140, the existing addition with the extensive openings facing rearwards and the size of the garden, the proposed rear extension would not cause unacceptable harm to the living conditions of the occupiers of this neighbouring property by reason of loss of outlook or a sense of enclosure.

The proposed alterations to the roof and the creation of a gable projection at roof level would add bulk to the appeal property. However, the increase in the ridge height of the roof would not be significant and the roof of the gable projection would slope away from the shared boundary with No. 140. Even when assessed in conjunction with the single storey rear extension, the alterations to the roof and the erection of gable projection would not result in an unacceptable sense of enclosure or outlook for the occupiers of this neighbouring property.

The resulting property would not be an overbearing form of development for the occupiers of No. 140. Further, because of the relationship between the property and No. 146, the siting and bulk of the appeal scheme would not result in an overbearing form of development for the occupiers of this neighbouring property. These judgements take into account the changes in the ground levels of the 3 dwellings.

For the reasons given, it is concluded that the proposed development would not cause unacceptable harm to the living conditions of the occupiers of the neighbouring properties and, as such, there would not be a conflict with [name] 69 and 70 to ensure that the amenity of neighbouring properties are not being unacceptably harmed, particularly where the 3 metre depth of rear extensions is not an absolute limitation.

The Council has suggested several conditions in the event this appeal succeeds which have been assessed against the tests in the Framework and the Planning Practice Guidance. For reasons of clarity, a condition is necessary to secure the erection of the proposed development in accordance with the approved drawings. To assist with the assimilation of the appeal scheme into the surrounding area a condition for the external materials to match those of the property is necessary.

Exceptionally, to protect the privacy of the occupiers of No. 140 a condition is necessary concerning the erection of obscure glazing and limited opening of the windows within the property’s south western elevation. Accordingly and for the reasons given, it is concluded that this appeal should be allowed.