Sin gle storey rear/side extension

Appeal Decision Site visit made on 20 June 2025 by G Ellis BSc (Hons) MSc MRTPI an Inspector appointed by the Secretary of State Decision date: 02 July 2025 Appeal Ref: APP/J1915/D/25/3361554 12 Datchworth Green, Datchworth, Knebworth, Hertfordshire SG3 6TL  The appeal is made under section 78 of the To wn and Country Planning Act 1990 (as amended) against a refusal to grant planning permission.  The appeal is made b y Mr David Holland against the decision of East Hertfordshire District Council.  The application Ref is 3/24/1965/HH.  The development proposed is a sin gle storey rear/side extension. Decision 1. The appeal is dismissed. Preliminary Matters 2. A revised plan, reference 2435 P203 Re v D, has been submitted as part of the appeal. The only difference with Rev C forming part of the application is the annotation regarding the materials for windows and doors, which is noted as white UPVC rather than painted wood. The planning application form refers to both options, and the existing house has UPVC windows. As such, this revised plan effectively amends the annotation and does not materially alter the proposal; I have therefore accepted this plan. Main Issues 3. The main issues are whether the proposed extension would be inappropriate development within the Green Belt and, if so, whether other considerations clearly outweigh the harm to the Green Belt so as to amount to very special circumstances. Reasons 4. Policy GBR1 of the East Herts Distri ct Plan 2018 (EHDP) indicates that planning applications within the Green Belt will be considered in line with the provisions of the National Planning Policy Framework (the Framework). The Framework establishes that development within the Green Belt should be regarded as inappropriate unless one of the specified exceptions applies. Exception (c), as set out in paragraph 154 of the Framework, allows for the extension and alteration of a building, provided that it does not result in disproportionate additions over and above the size of the original building. 5. Together with previous extensions, t he Council advises that the proposal would result in a 197% increase in footprint and a 177% increase in floorspace compared to the original dwelling. The appellant’s figures are lower as a garage and carport Appeal Decision APP/J1915/D/25/3361554 2 are included as part of the original. There are no plans or specific details before me of the property as it existed at the relevant date of July 1948. Nevertheless, even on the basis of the appellant’s approach, the combined increase in footprint would be 73%. This is considerably lower than the Council’s figure; it is still, nonetheless, a significant increase. 6. Neither the EHDP nor t he Framework provide a definition of ‘disproportionate additions’, and therefore it is a matter of judgement. In itself, the proposed single- storey extension is relatively modest in relation to the existing size of the house. It would wrap around the northeast corner and would not protrude further than other existing parts of the building. The property sits within a large plot, and I agree with the main parties that the extension would have a limited visual impact and would not be visible from the road. However, these aspects do not directly alter the assessment against the original building. Cumulatively, with the previous extensions there would be a substantial increase in the size of the property compared to the original building (with or without the inclusion of the garage and carport), resulting in disproportionate additions. The proposal would therefore be inappropriate development, contrary to exception 154(c) and, by definition, harmful to the Green Belt. 7. The appellant has not directly disputed t he scale of the cumulative extensions but considers that there would be no visual impact, or harm to the green belt purposes and refers to other exceptions. I accept on its own that the scale and form of this individual extension would not directly affect the purposes of the Green Belt. While there would be a small spatial change, considering the context in relation to the plot and its location within a residential area, there would be negligible harm to the overall openness of the Green Belt. 8. The appellant highlights that the site is within a defined settlement and promotes the consideration of the development pursuant to exceptions e) and g) of paragraph 154 of the Framework and as ‘Grey Belt’. These allow for infilling and other development in the Green Belt, in villages, and on previously developed land. However, in accordance with the definition of previously developed land (as set out in Annex 2: Glossary to the Framework) it excludes residential gardens within built- up areas. The appeal site, therefore, falls outside the scope of exception g) and Grey Belt. 9. Additionally, in my view, the proposal wo uld not be infilling, which is generally taken to be development within a gap between existing buildings, and as the proposal is for an extension to an existing building, it clearly falls to be assessed under exception (c). The proposal would therefore be inappropriate development and contrary to the Framework and EHDP policy GBR1. Other considerations 10. The proposal would create a larger dining room and an enhanced relationship to the garden with a ramped access. The Council has not raised any conflict with EHDP policy VILL2 or identified any other harm in relation to the character and appearance of the area or impact on neighbours, and I have no reason to disagree. Other than on Green Belt grounds, there are no objections to the proposed extension. However, the absence of harm in other respects is not a positive consideration, as acceptability in design and amenity terms is to be expected. Appeal Decision APP/J1915/D/25/3361554 3 11. Reference has been made to a planning permission which has been granted for an extension to a car park and replacement garage adjacent to 4 Datchworth Green. Whilst it is also within the Green Belt, it does not relate to an extension of a residential property and is not directly comparable to the appeal proposal. Additionally, the Council’s considerations in relation to that application are a separate matter outside the scope of this appeal. Green Belt Balance and Conclusion 12. The proposal would be inappropriate development within the Green Belt. In accordance with the Framework, substantial weight should be given to any harm to the Green Belt. Even taken together, the other considerations put forward provide little support for the scheme. Therefore, they do not outweigh the harm to the Green Belt, and the very special circumstances necessary have not been demonstrated. There would be conflict with the Framework and the development plan, and there are no other material considerations which outweigh that finding. Therefore, for the reasons given, the appeal is dismissed. G Ellis INSPECTOR