Annex at Mollcroft, Hempstead Lane, Potten End, BERKHAMSTED, HP4 2RZ

Annex at Mollcroft, Hempstead Lane, Potten End, BERKHAMSTED, HP4 2RZ — Dacorum Borough Council — Appeal Decision Site visit made on 29 April 2025 by S J Warder BSc(Hons) MA DipUD(Dist) MRTPI an Inspector appointed by the Secretary of State Decision date: 2nd May 2025 Appeal Ref: APP/A1910/W/24/3355387 Annex at Mollcroft, Hempstead Lane, Potten End, BERKHAMSTED, HP4 2RZ • 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 Ms Linda Brasier against the decision of Dacorum Borough Council. • The application Ref is 24/00157/FUL. • The development proposed is change of use for an existing detached residential annex building to a separate dwellinghouse. Decision 1. The appeal is dismissed. Preliminary Matter 2. The National Planning Policy Framework (the Framework) has been updated since the appellant’s statement was submitted. However, while the numbering of some of the paragraphs relevant to the appeal has changed, their substance has not. I have taken into account the updated Framework and referred to its paragraph numbering in this decision. Main Issues 3.

Annex at Mollcroft, Hempstead Lane, Potten End, BERKHAMSTED, HP4 2RZ — Dacorum Borough Council — Appeal Decision The main issues in this case are: • whether the proposal would be inappropriate development in the Green Belt (GB) having regard to the Framework and relevant development plan policies; • the effect of the proposal on the Chiltern Beechwoods Special Area of Conservation (SAC); • whether any harm by reason of inappropriateness, and any other harm, would be clearly outweighed by other considerations, so as to amount to the very special circumstances required to justify the proposal. Reasons Whether inappropriate development? 4. Framework paragraph 153 confirms that inappropriate development is, by definition, harmful to the GB and requires substantial weight to be given to any harm to the GB. Paragraph 154 advises that the re-use of permanent and substantially constructed buildings is not inappropriate development provided that openness is preserved. Dacorum Core Strategy (CS) Policy CS5 has similar aims. https://www.gov.uk/planning-inspectorate

Annex at Mollcroft, Hempstead Lane, Potten End, BERKHAMSTED, HP4 2RZ — Dacorum Borough Council — Appeal Decision Appeal Decision APP/A1910/W/24/3355387 5. There is no dispute that the appeal building is permanent and substantially constructed. It is a detached, single storey building erected as an annexe to Mollcroft under planning permission reference 20/00227/FHA. It is clear from the Council’s consideration of that application that it regarded the annexe as inappropriate development. Consent was granted due to the need to provide accommodation for a relative of the occupier of Mollcroft which the Council considered amounted to very special circumstances. Accordingly, a condition on the permission requires use of the annexe to be ancillary to the residential use of Mollcroft and not as a separate residential unit. 6. The current proposal is a free-standing application to use the annexe as a separate dwelling. Nevertheless, it seems likely that the appeal building would not exist without the particular circumstances which led to the original permission. As such, they are relevant to the appeal. 7. Mollcroft occupies a large plot. The appeal building sits within the plot and, as befits an annexe, there is no demarcation between the two buildings.

Annex at Mollcroft, Hempstead Lane, Potten End, BERKHAMSTED, HP4 2RZ — Dacorum Borough Council — Appeal Decision Use as a separate dwelling would inevitably require the creation of a boundary between the two plots. Whatever the exact form of the boundary, the resulting sub-division would result in an increased sense of enclosure of the land. Moreover, a separate dwelling would likely lead to increased domestic paraphernalia and the need to formalise and increase the currently informal and unobtrusive access and parking provision. 8. These effects would be particularly apparent given the location of the appeal site on the edge of the built-up area. In its current form, the annexe appears as a subservient building within the Mollcroft plot and gives the built-up area a relatively soft, open edge. The effects of creating a separate dwelling would intensify and formalise that edge, as well as emphasizing the siting of the annexe behind the general building line on the north side of the road. These concerns are not overcome because the development density would remain low. 9. I recognise that the site is reasonably well screened and that limits the visual effects of the proposal, but the effects would also be spatial. I have also had regard to the nearby recently constructed dwelling.

Annex at Mollcroft, Hempstead Lane, Potten End, BERKHAMSTED, HP4 2RZ — Dacorum Borough Council — Appeal Decision While that has extended the built-up area on the south side of the road, it does not bear on the effects of the proposal on the openness of the appeal site itself. I also appreciate that the proposal would not change the size or external appearance of the appeal building. The appellant argues that means of enclosure could be erected using permitted development rights. However, it has not been explained why the occupier of the existing single plot may choose to erect an enclosure of the length required to separate the two proposed plots. 10. Taking all these factors into account, I consider that the proposal would not preserve the openness of the GB compared to the current arrangement and, therefore, would be inappropriate development in the GB. As such, it would not accord with Framework paragraphs 153 and 154 or with CS Policy CS5. Nor would it comply with CS Policy CS1 to the extent that it seeks to protect the GB or Policy CS12 insofar as it requires development to integrate with the streetscape character 11. The appellant has referred to seven case studies. The officer report for the Piccotts End scheme does not consider the implications of the proposed conversion on the appeal plot or surroundings.

Annex at Mollcroft, Hempstead Lane, Potten End, BERKHAMSTED, HP4 2RZ — Dacorum Borough Council — Appeal Decision As such, it does not offer a robust justification for the appeal proposal where I have found that those changes would be harmful to openness. Case law and policy on GB openness has evolved since the Little Poppin https://www.gov.uk/planning-inspectorate 2

Annex at Mollcroft, Hempstead Lane, Potten End, BERKHAMSTED, HP4 2RZ — Dacorum Borough Council — Appeal Decision As such, it does not offer a robust justification for the appeal proposal where I have found that those changes would be harmful to openness. Case law and policy on GB openness has evolved since the Little Poppin https://www.gov.uk/planning-inspectorate 2

Annex at Mollcroft, Hempstead Lane, Potten End, BERKHAMSTED, HP4 2RZ — Dacorum Borough Council — Appeal Decision Appeal Decision APP/A1910/W/24/3355387 case was determined. Nevertheless, the Inspector considered the effect on openness on a site-specific basis. I have done the same and we have both reached conclusions based on the respective merits of the proposals. 12. Limited information has been provided on the Maple Hill case, but again, it would be reasonable to assume that openness was considered on a site-specific basis. The Tippings Meadow case differs from the current proposal in that no external works were proposed and there was no dispute over the effects on openness. The Winwood case differs in that the effect on openness by the creation of a small residential curtilage was more than off-set by the reduction in other built form on the site. The consideration of openness in the Bell Common case also involved the removal of existing built form. The consideration of openness in the Macs Farm decision turned on site-specific factors. None of these cases leads me to reconsider my finding on the effects of the appeal proposal on the GB. Effect on the SAC 13.

Annex at Mollcroft, Hempstead Lane, Potten End, BERKHAMSTED, HP4 2RZ — Dacorum Borough Council — Appeal Decision The appeal site falls within the zone of influence of the SAC and the appellant does not dispute that it cannot be certain that the proposal would not lead to an increase in visitors which would exacerbate the harm to the designated area. On this basis the proposal would not accord with the Habitat Regulations and CS Policies CS25 and CS26. 14. However, a completed unilateral undertaking (UU) has been submitted which would secure financial contributions to mitigate the harm in accordance with the Chiltern Beechwoods SAC Mitigation Strategy. I consider that the UU meets the tests set out in the Community Infrastructure Levy Regulations and Framework paragraph 58. Consequently, it would bring the proposal into accordance with the Habitat Regulations and CS Policies CS25 and CS26 and overcome the second reason for refusal. Other Considerations 15. I recognise that the condition attached to the original permission does not require the annexe to be used for specialist housing. On the other hand, the proposal would create an additional housing unit in an area where the Council cannot demonstrate a five-year supply of housing. The Framework provides strong support in these circumstances.

Annex at Mollcroft, Hempstead Lane, Potten End, BERKHAMSTED, HP4 2RZ — Dacorum Borough Council — Appeal Decision However, since I have found that the proposal would harm the GB, Framework paragraph 11d)(i) and footnote 7 apply and the tilted balance in paragraph 11d)(ii) is not engaged. Moreover, the provision of a single housing unit carries limited weight. 16. I acknowledge that the proposal would be sustainably located, that safe access and parking could be provided and that it would offer a good living environment for existing and future occupiers. However, these attributes are to be expected and therefore carry little weight in favour of the proposal. Green Belt Balance 17. I have found that the appeal proposal would be inappropriate development in the GB and would significantly reduce its openness. I am required to give substantial weight to any harm to the GB. Conversely, I give limited weight to the benefit of the proposal in terms of its contribution to housing land supply. The absence of other harms, including the mitigation of effects on the SAC, also carries limited weight in favour. https://www.gov.uk/planning-inspectorate 3

Annex at Mollcroft, Hempstead Lane, Potten End, BERKHAMSTED, HP4 2RZ — Dacorum Borough Council — Appeal Decision Appeal Decision APP/A1910/W/24/3355387 Consequently, the other considerations in this case do not clearly outweigh the harm identified and the very special circumstances necessary to justify the development do not exist. Conclusion 18. For the reasons given above the appeal should be dismissed.

Annex at Mollcroft, Hempstead Lane, Potten End, BERKHAMSTED, HP4 2RZ — Dacorum Borough Council — S J Warder INSPECTOR https://www.gov.uk/planning-inspectorate 4