Single storey side extension and two storey rear extension

Appeal Decision Site visit made on 12 February 2025 by K E Down MA(Oxon) MSc MRTPI an Inspector appointed by the Secretary of State Decision date: 25 February 2025 Appeal Ref: APP/B1930/D/24/3350286 The Farmhouse, Round House Farm, Roestock Lane, Colney Heath, St Albans, AL4 0PP • 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 R Franklin Smith against the decision of St Albans City & District Council. • The application Ref is 5/24/0636. • The development proposed is a single storey side extension and two storey rear extension. Decision 1. The appeal is allowed and planning permission is granted for a single storey side extension and two storey rear extension at The Farmhouse, Round House Farm, Roestock Lane, Colney Heath, St Albans, AL4 0PP in accordance with the terms of the application, Ref 5/24/0636, subject to the following conditions: 1) The development hereby permitted shall begin not later than 3 years from the date of this decision. 2) The development hereby permitted shall be carried out in accordance with the following approved plans: 200, 206 rev D, 201 rev C, 207 rev G. 3) The materials to be used in the construction of the external surfaces of the development hereby permitted shall match those used in the existing building. Main Issue 2. There is one main issue which is whether the proposed development would amount to inappropriate development in the Green Belt, having regard to the National Planning Policy Framework (NPPF), 2024, and any relevant development plan policies. Reasons 3. The appeal dwelling is a large, detached, traditional, double fronted former farm house on a generous plot. It is located in a semi-rural location on a private road which also provides access to a group of modern dwellings, two further dwellings and a large agricultural style building. The private road is a Public Restricted Byway and continues into open countryside as an unmade track beyond the appeal site. The site lies within the Green Belt. 4. The NPPF identifies that the fundamental aim of Green Belt policy is to prevent urban sprawl by keeping land permanently open. It goes on to state that Appeal Decision APP/B1930/D/24/3350286 2 inappropriate development is, by definition, harmful to the Green Belt and should not be approved except in very special circumstances. For extensions and alterations to buildings, these should not result in disproportionate additions over and above the size of the original building. “Original building” is defined in the NPPF as a building as it existed on 1 July 1948 or, if constructed after 1 July 1948, as originally built. The appeal dwelling has been extended in the past. However, it is agreed between the parties that these additions pre-date 1 July 1948. Therefore, for the purposes of assessment against Green Belt policy the existing building is also the original building. 5. Policies 1 and 13 of the City and District of St Albans District Local Plan Review (LP), adopted 1994, taken together are broadly consistent with the NPPF insofar as they seek to apply national Green Belt policy to protect the openness and character of the Green Belt. The limited extension of existing dwellings is supported provided it is modest in scale so as not to create a significantly larger building, visually well integrated with the rural surroundings, has no significant impact on the character and appearance of the countryside and does not harm the ecology, natural beauty or amenity of the countryside. The Council’s Supplementary Planning Guidance: Residential extensions and replacement dwellings in the Green Belt (SPG), 2004, provides guidance on what may represent disproportionate additions. 6. The parties agree that the floor area of the original building is some 280m². Using the Council’s figures, the proposed extensions would add about 100m² to this and would increase the volume by some 374 m³. The resultant building would thus be some 35% greater in floor area than the original dwelling. The appellant’s floor area figures are smaller than the Council’s calculations, but it is unclear how they have been reached. I shall therefore use the Council’s figures which appear realistic. 7. The SPG provides guidelines on size ranges for extensions which might be acceptable of between 20% and 40% increase in floor area and up to 300m³ in volume. The SPG makes clear that these are not rigid limits and the Council’s main concern is to ensure that other criteria in the SPG are complied with. Moreover, the guidelines were established to take account of Permitted Development (PD) rights limits which applied at the time but which have since been removed. In general, larger extensions are now permitted as PD and therefore the Council’s guidance should be applied flexibly. 8. The Council’s SPG sets out seven further criteria against which extensions should be judged. The performance of the extensions against these then provides a guide as to what scale of extensions, within the range set, may be considered not to be disproportionate. I shall consider these in turn. 9. Firstly, under criterion (ii) it is agreed that the dwelling is “original” for Green Belt purposes. It therefore performs very well against this criterion. Secondly, the type of extensions are considered. Rear and single storey side extensions are generally viewed more favourably in the SPG, provided side extensions do not close important gaps. The single storey orangery would be a side extension but would face onto the large garden. The rear extension would be partly over existing single storey elements but would also infill an open L-shaped area at two storeys. The roof would be enlarged but would integrate well with the existing roof form. Overall, the extensions would appear well proportioned in the context of the original house, which would retain its character as a single dwelling, and well integrated into the Appeal Decision APP/B1930/D/24/3350286 3 semi-rural area. Contrary to the Council’s view, I therefore find that the proposed development would perform well against this criterion. 10. In terms of visibility from public viewpoints, there would be limited views of the rear extension, at a distance from Roestock Lane and some views from the private road/track. However, in none of these would the extension dominate or appear disproportionate. The single storey orangery would be visible from the track beyond the private road but the view would be partly obscured by dense boundary hedging and would have a negligible effect on public views. Moreover, no gaps between dwellings would be materially closed. Overall, the proposed extensions would therefore perform moderately to well against criteria (iv) and (v). 11. Turning to the other SPG criteria, I agree with the Council that there would be no conflict with LP Policies 69 or 72 which are design policies that apply to all extensions. Further, since no landscaping or trees would be affected and the site is neither a listed building nor within a Conservation Area the proposed extensions would have no adverse effect on these. They would therefore perform very well against the criteria. 12. Taking account of the SPG criteria as a whole, the proposed extensions perform well to very well. This would indicate that figures at or above the top of the range should be considered. The proposed extensions would add about 35% to the floorspace which would fall within the 20%-40% range. Although the increase in volume would be above the 300m³ maximum set out in the SPG, allowing that this should be applied flexibly owing to the reasoning behind the limits set and the age of the SPG, I consider that the increase would not be excessive. Overall, the extensions would be moderate in scale in the context of the original dwelling. Moreover, they would appear visually sympathetic. I therefore find that the proposed extensions would be modest in size and would not result in disproportionate additions to the original building. 13. It is concluded on the main issue that the proposed development would not amount to inappropriate development in the Green Belt. Accordingly, the proposed development would comply with LP Policies 1 and 13 and with national policy set out in the NPPF, 2024. The Council also refers to LP Policies 69 and 72 in its refusal notice. However, it is clear from the delegated report that no conflict with these policies is found. I agree with this view. 14. The courts have found that where development is not inappropriate it should not be regarded as harmful either to the openness of the Green Belt or to the purposes of including land in the Green Belt. I do not therefore need to consider the effect on openness. Neither is it necessary to consider whether very special circumstances exist, and the appeal should be allowed. 15. Turning to conditions, I agree with the Council that in addition to the statutory commencement condition, the development should be carried out in accordance with the approved plans and in materials that match the existing building. The Council also suggests a condition withdrawing permitted development rights for extensions and outbuildings. The reason given is in the interests of visual amenity and the openness of the Green Belt. However, limits on permitted development rights exist in order to protect visual amenity and the Government has not considered the general withdrawal of permitted development rights in the Green Belt to be necessary. The Council has not provided any specific justification for the Appeal Decision APP/B1930/D/24/3350286 4 withdrawal of permitted development rights in this case. I therefore consider that to do so would be contrary to the tests of reasonableness and necessity. I shall not therefore impose the suggested condition. 16. For the reasons set out above and having regard to all other matters raised, I allow the appeal. K E Down INSPECTOR