Appeal 3374249

The appeal is dismissed insofar as it relates to the double storey rear extension.

The appeal is allowed insofar as it relates to the single storey front extension and planning permission is granted for the single storey front extension at [site address] , Maidenhead [postcode] in accordance with the terms of the application, Ref 25/01410 and the plans submitted with it, so far as they are relevant to that part of the development hereby permitted and 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 no’s 2025/05/501, 2025/05/503 and 2025/05/504 except in respect of the double storey rear extension.

The external materials of the single storey front extension hereby permitted shall match those used in the existing dwelling.

The Council’s description of development on the decision notice varies from the application form by including reference to “demolition of existing elements”. Both the existing front porch and rear conservatory are clearly shown on the plans to be replaced by the proposed development. As such, the description provided on the application form is clear and adequate, as set out in the banner heading above.

The appellant has included amended plans as part of their appeal submission. These set out the demolition of a shed to the side elevation and a rear outbuilding. These amendments are a fundamental change and have not been part of a consultation process. The Planning Inspectorate’s ‘Procedural Guide: Planning appeals – England’ (February 2026) makes clear that what is considered by the Inspector at appeal is essentially the same scheme that was considered by the Council and by interested parties at the application stage. As such, I have not accepted the amended plans and have determined the appeal on the same basis as the Council.

The Council’s reasons for refusal relate to the proposed rear extension only and it is clear from its submissions that the Council does not have any concerns about the proposed front extension. On this basis, the main issues are as follows: • the effect of the proposed rear extension on the character and appearance of the local area and • whether the development would provide its occupants with acceptable living conditions with regards to private amenity space.

The Council’s delegated report refers to the RBWM Townscape Assessment (TA)(2010) which categorises the locality of the appeal site as an early post war residential suburb. Such areas typically comprise two storey semi-detached or terraced housing arranged in curvilinear streets creating a distinctive urban form with relatively simple architecture. Houses are positioned to allow for both front and rear gardens which contribute to their setting and spacious feel. The TA acknowledges that such areas have been subject to incremental changes and extensions to dwellings over time.

Queensway is representative of this characterisation, with the appeal site forming the left-hand component of a pair of semi-detached dwellings, regularly spaced and positioned along a curving street. Neighbouring and nearby properties have undertaken various extensions, with the conjoining property, number 27 having a similar front extension and two-storey rear extension of the same depth as that proposed by the appellant. Number 25 itself has benefited from a rear conservatory and a detached outbuilding of solid construction along the rear boundary of the plot.

The proposed rear extension would replace the existing conservatory with a two-storey addition, extending across the full width of the existing house and out into the rear garden. Given the positioning of the existing houses, visibility of the rear of the site would predominantly fall to surrounding dwellings with only a very brief glimpse possible from the street, between numbers 23 and [site address] .

A significant proportion of the rear space within the site is already taken up by the existing outbuilding and the addition of the extension would result in limited remaining space to serve the rear of the house. Whilst the neighbouring property has extended in a similar manner to that proposed, the cumulative impact of the proposed development with the existing outbuilding and shed at this site, would result in a cluttered plot, dominated by buildings and therefore at odds with the surrounding built pattern / character.

For this reason, the proposed rear extension would be harmful to the character and appearance of the local area, contrary to Policy QP3 of the Royal Borough of [site address] Borough Local Plan 2013 – 2033 (the Local Plan) which expects new development to respect and enhance local character.

The Council refers to the Royal Borough of [site address] Borough Wide Design Guide (2020) (BWDG) in relation to standards for private amenity space and has quantified the resulting amenity space at the site as being significantly less than what would be required for a new dwelling of similar size. Notwithstanding that the proposed development is not a new dwelling, principle 10.1 of the BWDG applies, which amongst other matters, emphasises the importance of retaining suitable and sufficient quality private amenity space when considering household extensions.

As referenced above, the siting and size of the proposed development, in conjunction with the existing outbuilding, would take up a significant proportion of the rear amenity space serving the dwelling. An ‘L’ shape would be retained around the extension which would not provide adequate space for typical domestic activities such as drying clothes or outdoor seating. Space to the side of the dwelling is taken up by an existing wooden shed and the front area is laid with gravel for off road parking and therefore would not be useable for private amenity purposes in lieu of space to the rear.

I conclude that the development would not provide its occupants with acceptable living conditions with regards to private amenity space. Therefore, the proposed development would be contrary to Policy QP3 of the Local Plan, the accompanying BWDG, and the National Planning Policy Framework all of which require development to provide sufficient levels of high-quality private amenity space for existing and future occupiers.

There is reference to communication issues between the Council and the agent / appellant both during and after the planning application process however, these are not matters for my resolution in the context of a planning appeal.

For the reasons set out above, the appeal is dismissed in relation to the proposed double storey rear extension. However, the proposed single storey front extension is clearly severable from the rear extension being both physically and functionally independent. Therefore, in this case, under section 79(1)(b) of the Town and Country Planning Act 1990, I am able to issue a split decision and grant planning permission for the front extension.

As part of the grant of planning permission, legislation requires the imposition of a condition specifying the period for commencement of the development. In addition, I am imposing conditions identifying the relevant drawings to provide certainty, and for materials to match those used on the existing house to maintain the character and appearance of the local area.

For the reasons given above, the appeal should be allowed in part and dismissed in part.