Described on the planning application form as ‘Retrospective planning application for conversion of existing garage and gym into granny annex

Appeal Decision Site visit made on 9 September 2025 by Alison Fish BA (Hons) Dip TP MRTPI an Inspector appointed by the Secretary of State Decision date: 26 September 2025. Appeal Ref: 6000274 434 Main Road, Biggin Hill, Bromley TN16 2HW • 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 Francis against the decision of the Council of the London Borough of Bromley. • The application Ref is DC/23/00636/FULL6. • The development is described on the planning application form as ‘Retrospective planning application for conversion of existing garage and gym into granny annex’. Decision 1. The appeal is allowed and planning permission is granted for conversion of existing garage and gym into granny annex to be occupied only as part of the dwelling known as 434 Main Road at 434 Main Road, Biggin Hill, Bromley TN16 2HW in accordance with the terms of application Ref DC/23/00636/FULL6, and the plans submitted with it, subject to the followings conditions: 1) The development hereby permitted shall be carried out in accordance with drawing number EX.01. Preliminary Matters 2. I have taken the description in the banner heading above, from the planning application form. However, in my formal decision I have omitted words which are not acts of development and included additional wording to reflect the basis on which I have determined the appeal. I will return to this matter later 3. The planning application was submitted retrospectively and I understand that at the time of my site visit, the appeal development was occupied by carers. 4. The appeal site is located within the Green Belt. There is no dispute between the main parties that the appeal development constitutes the re-use of a building that is of permanent and substantial construction. There is also no dispute that as the siting, scale and mass of the appeal development is not materially different from its use as a garage and gym, it would preserve the openness of the Green Belt and not conflict with the purposes of including land within it. I have undertaken a site visit and find no reason to disagree. The appeal development is therefore not inappropriate development in the Green Belt with reference to Paragraph 154 h) iv of the National Planning Policy Framework. Appeal Decision 6000274 2 Main Issue 5. The main issue in this appeal is whether the development comprises a use which is part and parcel of the main dwelling or a new self-contained dwelling. Reasons 6. The host dwelling is a detached property located in large grounds with a substantial driveway and parking area to the front and side. The building the subject of this appeal was formerly a double garage and gym. It is located close to, but detached from, the host dwelling. 7. The appeal building has been converted to provide living accommodation comprising two bedrooms, a bathroom and a living area including a kitchen. There is a raised deck area to the rear providing an outdoor seating area. Access is provided from the driveway and parking area to the front of the property via a ramped access to a door on the side elevation. 8. The degree of separation from the main house together with the living accommodation it provides means that it has the necessary facilities for independent living and could be occupied as a separate dwelling. At 58.2 square metres (sqm) of accommodation it is not a small unit, but it would fail to meet the minimum gross internal floor area of 61 sqm for a 2 bedroom, 3 person dwelling as set out in the ‘Technical Housing Standards - nationally described space standards’1. The Council say that this would lead to a dwelling which provides sub- standard accommodation leading to overdevelopment of the site, at odds with the character of the area. 9. However, a new dwelling is not before me. The application form clearly refers to the use of the building as an annex and it is clear from the submissions accompanying both the planning application and the appeal that it is intended to provide accommodation to assist with the full time care of an occupier of the host dwelling. 10. The annex has a functional connection with the main house. It is clear from the appellant’s submissions that it shares utilities with the main house and is not separately metered. The evidence indicates that the occupants of the property would provide care and support for occupiers of the host property providing a strong functional link between the two buildings. 11. Despite being contained within a detached building, the annex also has a physical connection to the main house. It is attached to the main dwelling by a wall which forms the boundary with the rear garden of the main dwelling. Despite having its own private decking area to the rear, a gate provides direct access from the deck into the rear garden of the host dwelling. It shares the existing vehicular access and parking with the host dwelling and is visually well related to the host dwelling being immediately adjacent. 12. Whilst I acknowledge that the annex contains facilities required for a separate dwelling, they are also the type of facilities you would expect to see in a residential annex. I have also found that in this instance the annex has a physical, functional and visual relationship with the host dwelling. Accordingly, the concerns of the Council relating to the overdevelopment and over intensification of the site do not arise. 1 Department for Communities and Local Government March 2015 Appeal Decision 6000274 3 13. The proposal does not conflict with Policies 7 and 37 of the Bromley Local Plan adopted January 2019 which relate to extensions to provide accommodation for family members and the need for a healthy living environment for future occupiers. Conditions 14. As the work has already been carried out, it is not necessary to attach the standard time condition. However, it is necessary to specify the approved plans in the interests of certainty. 15. I have amended the description of development in my formal decision to reflect that the annex is to be occupied as part and parcel of the main house. Accordingly, a condition to ensure that the building is only occupied as annex is not necessary as a material change of use to a separate dwelling would require the grant of planning permission. Conclusion 16. For the reasons set out above, I conclude that the appeal should be allowed. Alison Fish INSPECTOR