Erection of conservatory at the rear of the house

Appeal Decision Site visit made on 11 March 2026 by SJ Desai BSc MSc MRTPI an Inspector appointed by the Secretary of State Decision date: 02 April 2026 Appeal Ref: 6003995 116 Lymington Road, Dagenham, Barking and Dagenham RM8 1RS • The appeal is made under section 78 of the Town and Country Planning Act 1990 against a refusal to grant planning permission. • The appeal is made by Kimberly Adams against the decision of the Council of the London Borough of Barking and Dagenham. • The application Ref is 25/01605/HSE. • The development is erection of conservatory at the rear of the house. Decision 1. The appeal is dismissed. Main Issues 2. The main issues are the effect of the development on the: • character and appearance of the host dwelling and surrounding area, with due regard to the Becontree Estate, a non-designated heritage asset; • living conditions of the occupiers of 118 Lymington Road (No.118), with particular regard to outlook, daylight and overshadowing. Reasons Character and appearance 3. The appeal relates to a two-storey mid-terrace dwelling located within a predominantly residential area, although commercial development lies to the east. The immediate area is characterised by properties of a consistent scale and form. Rear gardens display a uniform pattern of depth, aligned boundaries, and a sense of openness when viewed collectively from the dwellings themselves and across rear gardens. Development typically remains subservient and does not extend significantly into plots, maintaining a clear rhythm of built form and open space. This pattern forms an integral part of the established urban grain and contributes positively to the character and appearance of the area. 4. The appeal site also lies within the Becontree Estate, which is identified as a non- designated heritage asset. Its significance derives principally from its planned layout, the uniformity of built form, and the regularity of its urban structure and street pattern. Appeal Decision 6003995 2 5. The host dwelling has been subject to a previous ground floor extension. During my site visit, I also observed a comparatively substantial detached outbuilding within the rear garden. As a result, the remaining garden area is relatively limited in size. 6. The adjacent properties, 114 (No.114) and 118 (No.118) Lymington Road, remain largely unaltered to the rear, and the overriding character is one in which the openness of rear gardens remains a defining feature. Whilst there are examples of extensions and outbuildings within the wider terrace, including at 124 Lymington Road, the planning history in such cases is unknown. In any event, these do not disrupt the prevailing and defining characteristics of modest dwellings and undeveloped rear gardens. 7. The proposal would comprise a single storey rear conservatory with a flat roof, extending to an overall depth of approximately 5.5m when combined with the existing rear extension. The total depth represents a clear and substantial exceedance of the guidance set out within the Council’s Residential Extensions and Alterations Supplementary Planning Document (2012) (the SPD). The resulting form and scale of development would appear disproportionate to the modest scale of the host dwelling and would fail to read as a subordinate addition when viewed from neighbouring dwellings and gardens. It would erode the legibility of the original form of the dwelling and detract from its simple and uniform character. The flat roof design would not sufficiently mitigate the visual impact arising from the cumulative depth and overall massing proposed. 8. The combined footprint of built development, when taken together with the existing outbuilding, would occupy a substantial proportion of the plot, leaving a materially reduced area of usable garden space that fails to maintain the established balance between built form and open space which is a prevalent and characteristic feature of the locality and disrupts the established rhythm of the urban grain. 9. Although the rear garden areas are not prominent in public views, they nonetheless form an important component of the character and quality of the residential environment. The incremental loss of openness through excessive extensions can undermine that character and, in this case, the degree of proposed site coverage and loss of openness would not result in good design. 10. The appellant highlights that the proposal would retain a level of private amenity space consistent with one of the requirements of Policy D6 of the London Plan (2021) (LP). However, compliance with such standards does not override the requirement for development to be of a high-quality design and remain proportionate and respectful of the surrounding context or justify a form of development that is harmful to the appearance of an area. 11. The Council also referred to Policy D5 of the LP. However, as this relates primarily to inclusive design and accessibility, I have found no conflict with this policy. Nevertheless, this is a neutral matter and does not weigh in favour of the proposal. 12. Whilst I have identified harm to the character and appearance of the area arising from the cumulative scale and depth of the proposal, I do not consider that this harm extends to the significance of the non-designated heritage asset. The proposal would not materially affect the key characteristics of the estate as experienced within the public realm, which are fundamental to its significance. This is a neutral matter and does not weigh in favour of the proposal. Appeal Decision 6003995 3 13. For the reasons set out above, I conclude that the proposal would harm the character and appearance of the host dwelling and surrounding area. As such, it would conflict with Policies D1, D4 and D6 of the LP and Policies SP2, DMD1 and DMD5 of the London Borough of Barking and Dagenham’s Local Plan 2020-2037 (2024) (BDLP) which, when read together require new development to be of a high- quality design and relate to its local context. The proposal would also conflict with the guidance of the SPD which, amongst other things, seeks to ensure that extensions are subordinate to a host dwelling and avoid overdeveloping a plot. The proposal would also conflict with the National Planning Policy Framework (the Framework), which seeks to ensure that developments are visually attractive and add to the overall quality of the area. Living conditions 14. No. 118, which adjoins the appeal property to the north, retains its original rear elevation and has not been extended. Within the constrained context of a mid- terrace arrangement, the proposal would result in a notable increase in depth of built form extending along the shared boundary. 15. Given the relatively limited width of the rear elevation of No.118 and the resulting proximity of the proposal to the neighbouring rear elevation windows, which are likely the primary sources of light and outlook for the rooms they serve, and to its immediate garden area, the proposal would appear unduly dominant. It would give rise to a strong sense of enclosure and an overbearing presence when experienced from within the dwelling and garden of No.118. Whilst the extension would be single storey with a flat roof, its excessive depth and close proximity to the shared boundary would nonetheless result in a material loss of outlook and increased sense of enclosure, leading to gloomy and oppressive living conditions for the occupiers of the neighbouring property. 16. Furthermore, having regard to the relative orientation of the properties, the proposal would also increase the potential for loss of daylight and overshadowing, particularly during times of lower sun path, compounding the impact upon the living conditions of neighbouring occupiers at No.118. 17. In contrast, whilst the proposal would be of a similar depth in relation to No.114, and would therefore give rise to a comparable degree of change in outlook along the shared boundary, I note that this property lies to the south of the appeal dwelling and that the relationship between the extension and the nearest rear windows differs from that at No.118. Taken together, the extension would not give rise to the same level of harm in terms of enclosure or loss of light as identified for No.118. The orientation of the properties would limit the extent of any overshadowing. Consequently, when taken as a whole, the impacts on the living conditions of the occupiers of No.114 would not be of such a magnitude as to warrant a finding of unacceptable harm. 18. The appellant refers to the existing boundary treatment and planting as mitigating factors. However, the existing boundary fence is modest in height, and no meaningful vegetation was evident at the time of my visit. Regardless of this, the impact of a solid extension wall by virtue of its permanence and massing would be markedly more dominant and enclosing than a boundary fence. In light of the foregoing, I do not find these factors overcome the harm identified. Appeal Decision 6003995 4 19. I have had regard to the appellant’s contention that Policy D4 of the LP and Policy SP2 of the BDLP are not wholly applicable on the basis that they do not explicitly reference residential amenity. However, both policies are concerned with delivering high-quality design and place-making, which necessarily includes consideration of how development relates to its surroundings and the effect on the living conditions of neighbouring occupiers. As such, these policies carry weight in my determination. 20. Accordingly, I conclude that the proposal would result in significant harm, that is not adequately mitigated by other material considerations, to the living conditions of the occupiers of No. 118, with particular regard to outlook, daylight and overshadowing. The proposal therefore conflicts with Policy D4 of the LP and Policies SP2, DMD1 and DMD5 of the BDLP. These require, amongst other things, good design and that development has a positive relationship with existing and nearby properties. For the same reasons, the proposal also conflicts with the guidance contained within the SPD and Section 12 of the Framework. Other Matters 21. While the SPD is expressed as guidance and uses qualifying language such as ‘normally’, this does not diminish the relevance of its underlying design principles, which are firmly rooted in and supported by policies within the BDLP. Furthermore, the Framework makes clear that good design is a key aspect of sustainable development, and that development which fails to achieve a high standard of design should not be regarded as sustainable development. Accordingly, the SPD is a material consideration and has been afforded appropriate weight in my assessment. In this case, I have seen no convincing evidence to demonstrate that there are specific site circumstances or other material considerations that would justify a departure from that or the guidance and the development plan policies. 22. Whilst I understand the wishes of the appellant to secure additional living space, I do not consider that these personal circumstances provide sufficient justification to outweigh the harm I have identified from the proposal. Conclusion 23. For the reasons given above, the development conflicts with the development plan taken as a whole and there are insufficient material considerations, including the provisions of the Framework, to indicate that the proposed development should be determined otherwise than in accordance with it. The appeal should therefore be dismissed. SJ Desai INSPECTOR