Appeal 6003733

The appeal is allowed and planning permission is granted for single storey rear extension at [site address] , [site address] , Hertfordshire [postcode] in accordance with the terms of the application, Ref 25/1989/FUL, subject to the following conditions:

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

The development hereby permitted shall be carried out in accordance with drawing nos A2025007.PA101 REV P02,A2025007.PA102 REV P02, A2025007.PA103 REV P02, A2025007.PA104 REV P02, A2025007.PA105 REV P02, A2025007.PA109 REV P02.

The external surfaces of the development hereby permitted shall be constructed in the materials shown on plan no. A2025007.PA104 REV P02 and the submitted application form.

Notwithstanding the provisions of the Town and Country Planning (General Permitted Development)Order 2015 (or any other revoking and re-enacting that order with or without modification), no windows/dormer windows or similar openings [other than those expressly authorised by this permission], shall be constructed in the flank elevations or roof slopes of the extension hereby approved.

Prior to the first use of the extended patio hereby permitted, the 1.8m high (from patio floor level) solid privacy screen as shown on drawing number A2025007.PA102 REV P02 shall be erected for a depth of 2.6m to the side adjacent to No. [address] and the existing privacy screen adjacent to No. [address] shall be retained. The privacy screens shall be permanently maintained as such thereafter.

The description of development used in the formal decision and banner heading has been taken from the application form. The Council’s Decision Notice uses a different description of development, but I have not been provided with any confirmation that this amended description has been agreed.

The main issue is the effect of the proposed development on the living conditions of the neighbouring occupiers at No [address] (No 36) with particular regard to light and outlook.

The appeal site relates to a two-storey semi-detached property with a long rear garden. At the rear of the dwelling, there is a modest single storey mono-pitched extension, conservatory and raised patio area, which then steps down to the lawned garden due to the change in land levels. [address] is on a hill, the appeal property sits higher than No 36 to the north, but slightly lower than the adjoining property, No 40.

No 36 has a part two-storey, part single-storey extension with a raised decking area that steps down to a lawned garden. The garden is long, with mature vegetation along its boundary with No 38. Unlike the lawned area, from the rear habitable rooms and area of decking at No 36, the difference in land levels between the immediate rears of Nos 36 and 38 does not appear substantially different, due to the gradual incline of [address].

No 36 is set further forward in its plot than that of the appeal property. Consequently, the flank elevation and the existing extension at No 38 are already prominent in views from the rear windows and decking at No 36 and have an effect on sunlight and daylight received by the rear ground floor habitable room windows and the decking area.

Appendix 2 of the Development Management Policies Local Development Document (2013) (DMP), amongst other matters, sets out that extensions should not be excessively prominent in relation to adjacent properties and should not result in a loss of light to the windows of neighbouring properties, it therefore suggests that single storey extensions should, generally, have a maximum depth of 3.6 metres in the case of semi-detached dwellings.

The proposed 6 metre, single-storey rear extension would span the full width of the rear elevation, replacing the existing extension and conservatory but would not extend beyond the existing flank wall. While the increased depth would be noticeable from the rear windows, decking and garden area of No 36, the proposal would feature a flat roof with a part mono-pitch that would slope up and away from the shared boundary to a maximum height of 3 metres. In this regard, the part of the proposed extension closest to, and most noticeable from, the rear elevation and decking at No 36 would have less bulk, massing and height than the existing extension at No 38.

Although the proposal would be deeper than the existing extension, it features a considered roof form and would be set back from the shared boundary by approximately 1.8 metres at its closest point, and over 2.5 metres where the extension reaches its maximum height of 3 metres. Consequently, I consider the proposal would not harmfully reduce sunlight and daylight to the rear habitable room windows and decking of No 36 over and above existing levels. Furthermore, it would not appear excessively prominent or harmfully reduce the occupiers primary outlook which would be maintained over their long rear garden.

Due to the change in land levels, the extension would appear more prominent when in the lawned garden area of No 36, than from the decking or rear habitable rooms. However, given the extension’s roof form and its set back from the shared boundary, with the separation distance gradually increasing across the depth of the extension, I am satisfied it would not appear visually incongruous and would not result in an overbearing or unneighbourly form of development.

The proposal would also incorporate a raised patio beyond the rear extension, including a retaining wall and privacy screen located close to the boundary with No

The patio would be set down from the ground level of the extension, with a further drop along the area closest to the shared boundary with No 36. Consequently, I find that the proposed retaining wall with privacy screen would not be substantially higher than the existing shared boundary. Given the limited length of privacy screen relative to the depth of the rear garden at No 36, I am not persuaded that it would be unduly overbearing or dominant, even when considered in combination with the proposed rear extension such that it would harmfully affect the living conditions of the occupiers of No 36 when in their garden. I am also mindful that the privacy screen would be largely screened by existing mature vegetation within the garden of No 36.

For the reasons above, the proposal would not have an adverse effect on the living conditions of the neighbouring occupiers at No 36 with regard to light and outlook. In this regard, although the proposal would exceed the 3.6 metre size guidance in Appendix 2 of the DMP, it would accord with its overall aims. It would also not conflict with Policies CP1 and CP12 of the [name] (2011) and Policy DM1 of the DMP, which taken together, amongst other things, seek to protect the living conditions of neighbouring occupiers and avoid extensions which are excessively prominent in relation to adjacent properties.

Concern has been raised regarding the effect of the proposal on the character and appearance of the area, including the nearby [site address] Conservation Area. However, within the [name], the Council found no policy conflict on this matter and it did not form a reason for refusal. On the basis of the evidence before me and my own observations, I have no substantive reasons to take a different view.

Reference has been made by an interested party that the proposal would exceed the 45-degree rule. Appendix 2 of the DMP makes reference to this, however it is only applicable to two storey extensions as well as consideration of a variety of matters, including land levels. The rule is primarily used to assess the impact of extensions to prevent unreasonable loss of light and overbearing impacts. [name] have found the proposal would be acceptable in these regards, even if I were to find it applicable, it would not alter my findings.

Concerns have been expressed that should the appeal be allowed, a precedent would be set which could lead to further large extensions on other nearby properties. However, this appears to be a generalised concern, and I have limited substantive evidence that allowing this appeal would result in similar planning applications coming forward. In any case, each proposal is considered on its own merits and site-specific circumstances, as I have done in this case.

The Council’s suggested conditions have been considered in accordance with Planning Practice Guidance and the Framework. In addition to the statutory time limit condition, a condition specifying the relevant drawings is necessary as this provides certainty. A condition relating to materials is necessary in the interests of the character and appearance of the area.

In the interests of safeguarding the living conditions of neighbouring occupiers, there is justification for the removal of permitted development rights to form new windows in the flank walls and roof slopes so as to avoid overlooking and maintain the living conditions of the occupiers of adjoining properties. For these same reasons it is also necessary to impose a condition to ensure a privacy screen is erected before the patio area is used.

The proposed development would not conflict with the development plan. There are no material considerations which indicate that the decision should be made other than in accordance with the development plan. Therefore, for the reasons given and subject to conditions, I conclude that the appeal should be allowed.