Construction of detached annexe

Appeal Decision Site visit made on 15 December 2025 by C Coles MRTPI an Inspector appointed by the Secretary of State Decision date: 15th June 2026 Appeal Ref: APP/P1425/D/25/3373143 The Old Mill Bungalow, Barcombe Mills Road, Barcombe, East Sussex BN8 5BS • The appeal is made under section 78 of the Town and Country Planning Act 1990 (as amended) against a refusal to grant planning permission. • The appeal is made by Mr and Mrs Bennett against the decision of Lewes District Council. • The application Ref is LW/25/0253. • The development proposed is construction of detached annexe. This decision is issued in accordance with section 56 (2) of the Planning and Compulsory Purchase Act 2004 as amended and supersedes that issued on 9 April 2026. Decision 1. The appeal is allowed and planning permission is granted for replacement of existing outbuilding with detached annexe to the side of the main house with decking linking both and including associated landscaping at The Old Mill Bungalow, Barcombe Mills Road, Barcombe, East Sussex BN8 5BS in accordance with the terms of the application, Ref LW/25/0253, subject to the following conditions: 1) The development hereby permitted shall begin not later than three years from the date of this decision. 2) The annexe hereby permitted shall not be occupied until the dwelling permitted under references LW/23/0414 and LW/2024/0122, has been substantially completed and occupied. 3) The external materials of the annexe hereby permitted shall match those approved in the dwelling permitted under references LW/23/0414 and LW/2024/0122. 4) The development hereby permitted shall be carried out in accordance with drawing nos: Proposed Elevations (09 rev P3 – Proposed S-W Elevations Sheet 2), Proposed Elevations (08 rev P3 – Proposed N-W Elevations Sheet 1), 06 rev P1 – Indicative Foundation Plan, Proposed Block Plan (04 rev P2 – Proposed Block Plan 1:200), Proposed Floor Plans (05 rev P3 – Proposed Roof and Floor Plans), Survey Plan (03 rev P2 Existing Site Survey), Proposed Block Plan (02 rev P2 – Proposed Block Plan 1:500), Location Plan (01 rev P2 – Location Plan), Flood Risk Assessment (3185/RE/04- 23/01). 5) The development shall be carried out in accordance with the submitted flood risk assessment (FRA) (ref 3185/RE/04-23/01, dated June 2023) and the following mitigation measures it details: Appeal Decision APP/P1425/D/25/3373143 2 • Finished floor levels for the main building and annexe shall be set no lower than 8.19 metres above Ordnance Datum (AOD). • The void maintenance plan outlined in Appendix A of the above FRA shall be maintained throughout the lifetime of the development. These mitigation measures shall be fully implemented prior to occupation and subsequently in accordance with the scheme’s timing/phasing arrangements. The measures detailed above shall be retained and maintained thereafter throughout the lifetime of the development. 6) The annexe shall be used only for purposes ancillary to the enjoyment of the host dwellinghouse and shall not be used as a separate unit of accommodation. Preliminary Matter 2. The description of the development in the banner heading is taken from the application form. The Council has used an amended form of wording on the decision notice which I consider more accurately reflects the development and therefore I have used this in my formal decision. Main Issues 3. The main issues are: • Flood risk; and • whether the proposal would comply with development plan policy on residential annexes. Reasons 4. The appeal site comprises an existing detached single storey dwelling with detached outbuilding within a large garden accessed via a long private track. Planning permission has been granted for a replacement dwelling on the site (LW/2023/0414, amended by LW/2024/0122). Planning permission was granted for a garage in 2024 and this development has commenced. The appeal site lies within a countryside location. 5. The proposed development is for an annexe with a ground floor comprising a kitchen/dining area and living area, main bedroom and bathroom and a first floor mezzanine area in the roof space with a guest bedroom and en suite as well as a study. The annexe would be linked to the main dwelling via external decking and is designed to enable multigenerational living for the appellants family. The overall floor area of the annexe would be 84sqm and the height would be 6.9m. The annexe would be constructed of the same materials as the replacement dwelling and the appeal has been determined on this basis. Flood risk 6. The proposed annexe would fall within Flood Zone 3. The appellants did not submit a development specific Flood Risk Assessment (FRA) for the proposal but submitted a site specific FRA prepared for the replacement dwelling on the site and confirmed the proposal would follow the same design approach as agreed with the Environment Agency (EA) for the replacement dwelling. The appellants Appeal Decision APP/P1425/D/25/3373143 3 consider that as the annexe would be tied to the occupation of the main dwelling, the approach of submitting the FRA for the main dwelling for this appeal would be acceptable. The appellants have also stated they would be happy for a similar condition as was placed on the main dwelling in relation to flood risk to be applied to the annexe. 7. The EA in their consultation response which was on the Council website for the appellants to view, have requested a FRA for the annexe. However, the appellants have submitted a site specific FRA which the EA did not acknowledge. I have reconsulted the EA with the submitted FRA and the EA have responded with no objection to the proposed development subject to conditions. I am therefore satisfied the proposal would not put the proposed occupants of the annexe at risk of flooding and would therefore comply with Core Policy 12 of the Lewes District Local Plan Part 1 (LLPP1) which seeks to reduce the number of properties that are at an unacceptable risk of flooding. Development plan policies on residential annexes 8. Policy DM29 of the Lewes Local Plan Part 2 (LLP2) sets out the key considerations in relation to garages and other buildings ancillary to existing dwellings, noting they will be permitted where given criteria are met, namely: (1) The size, scale, siting and design relates satisfactorily to the existing dwelling and its curtilage, the established street scene, and the character of the locality; (2) The use of materials is sympathetic to the character and appearance of the existing dwelling. Outside the planning boundaries…..garages and other ancillary buildings should be subordinate in scale and proportion to, and located in close proximity to, the principal dwelling; the use of ancillary accommodation as a separate dwelling will not be permitted and proposals should not be of a size or design, or be capable of severance, to form an additional dwelling or dwellings. 9. It is common ground that the proposed annexe would be subordinate in footprint and height to the replacement dwelling and would relate well to the replacement in terms of design and materiality. 10. Whilst the proposed annexe may be large, it remains smaller and subordinate to the replacement dwelling and would share the same access, parking and amenity space as the main dwelling, albeit with space to the side of the annexe which would be more private. The annexe would also drain foul and surface water back to the main house. The proposed positioning of the annexe and with a shared means of pedestrian access as the main dwelling demonstrates the annexe has not been designed to be sold off or let. 11. The site is large enough to accommodate an annexe of the size proposed. Whilst in a different location on the site it would be possible and practical to sever the annexe from the main dwelling, in these site specific circumstances it would be neither practical or desirable to do so. 12. The positioning of the annexe to the west of the replacement dwelling would mean that the residents of the annexe would need to walk directly in front of the main dwelling for pedestrian access, utilising the shared decking. The parking for the main dwelling and the annexe would be shared and located to the east of the main Appeal Decision APP/P1425/D/25/3373143 4 dwelling with no direct vehicular access to the annexe. It is also highly unlikely that a new vehicular access directly to the annexe could be provided due to the gradient of the site to the south of the annexe and the main dwelling and its location within the flood plain. Significant engineering works would be required to create a new access to the annexe which would require planning permission which would be under the control of the Council. For the reasons outlined above, it is highly unlikely the annexe would be able to be severed from the main dwelling. 13. The appellants have demonstrated their willingness to have a restrictive condition on the use of the annexe as ancillary accommodation enabling the Council to further control the use of the annexe and prevent it being severed from the main dwelling. In any event, the appellants have applied for an annexe and therefore the appeal should be taken at face value. The Council has enforcement powers in the event that the proposed development is not used as ancillary accommodation to the host dwelling. 14. In conclusion, the proposed development would meet the development plan criteria contained in policy DM29 of the LLP2 which permits ancillary buildings to existing dwellings. Conditions 15. I have had regard to the various planning conditions that have been suggested by the Council and appellant and have considered them against the tests in the Framework and the advice in the Planning Practice Guidance. 16. In the interests of certainty, I have imposed conditions specifying the relevant drawings, time limits and materials. 17. The appeal has been assessed on the basis that the replacement dwelling will be constructed. A condition is therefore necessary to ensure that the annexe is not occupied until the replacement dwelling has been substantially completed and occupied. 18. To reduce the risk of flooding to the proposed development and future occupants, a condition is imposed requiring the proposal to be carried out in accordance with the Flood Risk Assessment provided. 19. In order to prevent the creation of a separate dwelling on the site, a condition is imposed limiting the use of the annexe to purposes incidental to the enjoyment of the host dwelling and shall not be used as a separate unit of accommodation. Conclusion 20. For the reasons given above the appeal should be allowed. C Coles INSPECTOR