Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — by J Bowyer BSc(Hons) MSc MRTPI an Inspector appointed by the Secretary of State Decision date: 04 NOVEMBER 2025

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — Theresa's Cottage, Marden Hill, Hertford, Hertfordshire SG14 2NE • 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 P Warwick against the decision of East Hertfordshire District Council. • The application Ref is 3/24/2125/HH. • The development proposed was originally described as ‘roof conversion incorporating 3 new conservation rooflights to north elevation and a replacement rooflight to south elevation. Internal alterations to remove first floor partition walls, install new staircase between first floor and second floor, install new first floor and second floor partition walls’.

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — Theresa's Cottage, Marden Hill, Hertford, Hertfordshire SG14 2NE • The appeal is made under section 20 of the Planning (Listed Buildings and Conservation Areas) Act 1990 (as amended) against a refusal to grant listed building consent. • The appeal is made by Ms P Warwick against the decision of East Hertfordshire District Council. • The application Ref is 3/24/2126/LBC. • The works proposed are ‘roof conversion incorporating 3 new conservation rooflights to north elevation and a replacement rooflight to south elevation. Internal alterations to remove first floor partition walls, install new staircase between first floor and second floor, install new first floor and second floor partition walls’.

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. https://www.gov.uk/planning-inspectorate

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. https://www.gov.uk/planning-inspectorate Appeal Decisions APP/J1915/W/25/3366883 & APP/J1915/Y/25/3366886 Main Issues 5. The main issue for both appeals is the effect of the proposal on the special interest of the Grade II* listed building, ‘Marden Hill House, Service Block and Annexe’ and any of the features of special architectural or historic interest that it possesses. Reasons 6. The listed building includes a neo-classical style country house which the list entry dates to 1790-1794, albeit with earlier origins and later alterations including by Sir John Soane in 1818-1819. The main house is finished in buff brick with Portland stone dressings and includes a hipped mansard roof with central valley, a large full height bow feature to the garden elevation and a two-storey tetrastyle Ionic porch to the front which was added by Soane. A service block and annexe sit to the right side, but the form and proportions of the house remain clear and together with the quality of its detailing provide for an impressive and elegant building. 7. The service block has a red brick exterior and much simpler detailing, with features including a plat band, a hipped roof and a somewhat irregular pattern of fenestration.

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. It dates to the 18th Century, although the list description notes that it incorporates some 17th Century brickwork and the appellant indicates that it has been extended towards the west with two added bays in the late 18th/early 19th Century. Adjoining the west end of the service block range and wrapping around the side of the service courtyard is a 19th Century annexe which is also of red brick but which is of late Victorian/Edwardian style including a higher pitched roof with gable ends, moulded bargeboards and stacks with paired diagonal shafts to either side. The contrasting style and materials of the service wing and annexe provide clear visual distinction from the main house, with their more modest detailing, proportions and architectural quality further reflecting their historic service role and ancillary status within the hierarchy of the building. 8. Given the above, I find the significance and special interest of the listed building, insofar as it relates to these appeals, to be primarily associated with its architectural and historic interest as a fine example of a late Georgian country house with attendant service wing and later annexe.

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. Although there have been alterations including subdivision to form separate dwellings, significance also derives from the historic integrity of the building, to which the legibility of the historic plan-form, hierarchy of spaces and surviving historic fabric contribute. 9. The appeal dwelling occupies the former annexe and part of the western end of the service block range. Within the annexe, the attic level has been part converted for habitable use which the appellant indicates occurred in the 1960s and which involved the addition of a steep stair, removal of collar beams, and the insertion of partitions and a rooflight. Nevertheless, the information before me suggests that while there has been some modernisation, much of the historic layout within the annexe is otherwise generally intact. The annexe is a much later addition which does not share the same architectural quality as the main house, but the surviving historic fabric and plan form inform some understanding of its historic nature as an annexe within the evolution and hierarchy of the house, contributing to the special interest and significance of the listed building as an entity. 10.

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. The proposal includes the replacement of the existing attic rooflight which I observed is fairly conspicuous from the lawn to the main house as a large, modern addition projecting above the southern roof slope. The conservation-style rooflight https://www.gov.uk/planning-inspectorate 2

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. The proposal includes the replacement of the existing attic rooflight which I observed is fairly conspicuous from the lawn to the main house as a large, modern addition projecting above the southern roof slope. The conservation-style rooflight https://www.gov.uk/planning-inspectorate 2

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. Appeal Decisions APP/J1915/W/25/3366883 & APP/J1915/Y/25/3366886 which is proposed in its place would include a flush finish and glazing bar. It would better reflect the style and proportions of the building and in my view would be a far more sympathetic and less visually intrusive feature which would enhance the appearance and composition of the listed building with benefit to its special interest and significance. 11. The three new rooflights which are proposed to the northern roof slope would be positioned behind the hipped roof that extends from the service block range. This roof and the extruded stack on this side of the annexe which sits broadly at the end of the service block range would essentially conceal the rooflights to many potential views from ground level. Screening would not be complete with some views of the westernmost rooflight likely, but it was apparent from my observations at my visit that visibility would be limited and restricted to only a very small area. 12. Even if they were visible, the rooflights would be conservation-style set flush with the roof, and of limited size providing a much more visually recessive element than the chimney and gable end features.

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. There would be reasonable spacing between each rooflight so that they would be appreciated as discrete features, and even taken cumulatively, they would occupy only a very modest proportion of the host roof slope. 13. Given these factors in combination, I am satisfied that the rooflights would be a discreet and unobtrusive addition that would not harmfully disrupt the simplicity of the host roof slope or detract from the architectural integrity or composition of either the appeal dwelling or listed building as a whole. Externally, they would have a neutral effect on the building’s special interest and significance. 14. Internally, the insertion of rooflights would necessitate removal of sections of three rafters. There is no dispute between the main parties that the affected rafters are sawn timbers dating to the late 19th/early 20th century. However, while they may be of limited architectural merit and comparatively modern, there would still be a loss of historic fabric that is part of this phase of the building’s development.

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. That said, the extent of the fabric affected would be very small, and the majority of these and other rafters would be retained intact so that the overall construction and evolution of the property would remain legible. On that basis, I consider that harm to the special interest and significance of the listed building through the alterations to rafters would be negligible. 15. The proposal also includes a replacement staircase to serve the converted roofspace. The existing steps are a modern addition, and I am satisfied that their removal would not diminish the special interest of the building. However, the replacement stairs would require enlargement of the existing opening in the first-floor ceiling, resulting in the removal of sections of joists and further loss of historic fabric. Nevertheless, the extent of fabric affected would again be very small and the majority of the joists would remain intact so that the overall construction and evolution of the property would remain legible. Accordingly, I find that harm to the special interest and significance of the listed building through the enlarged stair opening would be negligible. 16.

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. The revised staircase position would also necessitate some reorganisation of the first-floor level, with the doorway to the central bedroom shifted west and the doorway to bedroom 2 which is currently set forward into the corridor moved back to be broadly level with the internal bedroom wall. The changes would result in a https://www.gov.uk/planning-inspectorate 3

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. The revised staircase position would also necessitate some reorganisation of the first-floor level, with the doorway to the central bedroom shifted west and the doorway to bedroom 2 which is currently set forward into the corridor moved back to be broadly level with the internal bedroom wall. The changes would result in a https://www.gov.uk/planning-inspectorate 3

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. Appeal Decisions APP/J1915/W/25/3366883 & APP/J1915/Y/25/3366886 loss of historic fabric and alterations to the plan-form which the appellant has not disputed is original. However, a condition could require that the existing bedroom doors were re-used which would reduce the extent of fabric that would be lost. The change in plan form would also be minor, and would not significantly alter or disrupt the overall layout of the annexe or understanding of its historic role or position within the hierarchy of the listed building. Taking these factors together, I find that harm to the special interest and significance of the listed building through the reordering of the first-floor would be very limited. 17. Within the attic level, previous alterations have seen the removal of three or so collar beams from the central section and associated works to strengthen purlins with additional timbers bolted on and raking struts installed. The submitted plans appear to suggest that the modern raking struts would be removed. In addition, there would be removal of four further collar beams to provide adequate headroom.

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. As with the rafters, these collars may be sawn timbers of limited architectural merit, but there would still be loss of historic fabric contemporaneous with this phase of the building’s development. The extent of fabric affected may be comparatively small, but there would be some erosion of the integrity of the building such that I find some harm to its special interest and significance. 18. Moreover, the appellant has provided no firm detail of any compensatory structural works that may be required to address the removal of the struts and further collars within the attic level despite this being a specific concern raised in the Council’s evidence. It is therefore unclear whether further invasive structural works could be required or what these would entail, and I am unable to reach any firm view as to the effect that such works may have on the special interest and significance of the listed building through loss of historic fabric or otherwise. Nor can I be confident that an acceptable solution could be provided to ensure the structural integrity of the annexe would not be compromised. 19. In addition, the proposed bathroom would require services and drainage.

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. The appellant notes that there is a capped off soil vent pipe/drain at the base of the east end gable wall, but there is little to substantiate their assertion that it ‘should be straightforward’ to link to this which limits my confidence that provision of services and drainage would not have further implications for historic fabric or the special interest and significance of the building. 20. Given that a clear understanding of potential harm to the special interest and significance of the listed building would be fundamental to the determination of whether or not the proposal would be acceptable in principle, it would not be appropriate to defer assessment of these matters to a condition. 21. Overall, I have found that externally, the installation of three new rooflights would preserve the special interest and significance of the listed building. However, there would be harm to the building’s special interest and significance through the loss of historic fabric associated with the insertion of rooflights and the enlarged stair opening causing negligible harm, and reordering of the first-floor level causing some further, albeit very limited, harm.

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. I am additionally unable to reach any clear view on the degree of harm that would result from internal alterations within the attic level associated with removal of beams and provision of services. I find for these reasons that the proposal taken as a whole would fail to preserve the special interest of the listed building and would cause it harm. https://www.gov.uk/planning-inspectorate 4

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. I am additionally unable to reach any clear view on the degree of harm that would result from internal alterations within the attic level associated with removal of beams and provision of services. I find for these reasons that the proposal taken as a whole would fail to preserve the special interest of the listed building and would cause it harm. https://www.gov.uk/planning-inspectorate 4

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. Appeal Decisions APP/J1915/W/25/3366883 & APP/J1915/Y/25/3366886 22. The National Planning Policy Framework (‘the Framework’) advises that when considering the impact of development on the significance of designated heritage assets, great weight should be given to the asset’s conservation, and the more important the asset, the greater the weight should be. It goes on to advise that any harm to, or loss of, the significance of a designated heritage asset (from its alteration or destruction, or from development within its setting), should require clear and convincing justification. 23. Notwithstanding the uncertainty around the effect of the removal of beams and provision of services to the bathroom within the attic level, I consider having regard to the scale of the proposal and how it would affect Marden Hill House, Service Block and Annexe as a whole that harm to the significance of the Grade II* listed building would be ‘less than substantial’ in the terms of the Framework. I further find that the collective harm arising from the insertion of rooflights, the enlarged stair opening and reordering of the first-floor level would be at a very low level within this category. 24.

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. Where a proposal will lead to less than substantial harm to the significance of a designated heritage asset, the Framework advises that this harm should be weighed against the public benefits of the proposal, including, where appropriate, securing its optimal viable use. 25. Public benefits may include heritage benefits, and I have found in this case that the replacement rooflight would benefit the special interest and significance of the listed building. Listed buildings are safeguarded for their inherent architectural and historic interest irrespective of whether or not views of the building can be gained. Even so, the visibility of the rooflight means that the heritage benefit of its replacement would be far more widely experienced than the harm associated with the internal alterations. 26. Moreover, the proposal includes the replacement of the existing steps up to the attic. The appellant indicates that these steps do not comply with regulations and from my observations of their narrow and very steep nature, I am in no doubt that they make accessing the attic space not only difficult but also somewhat dangerous.

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. Although the wider proposal would provide additional space for the appellant which would essentially comprise a private benefit, I consider the replacement stair complying with Building Regulations would offer a clear improvement to safety which in my view would be a public benefit. 27. The appellant additionally refers to improved thermal efficiency through introduction of roof insulation as part of the loft conversion works which would be an environmental benefit, but no firm details have been provided to demonstrate improvements and I consider these would be likely to be limited in scale. 28. I have given considerable importance and weight to the harm to the listed building, but in my view, these benefits taken together would be of sufficient magnitude to outweigh the very low level of less than substantial harm that would cumulatively be caused by the insertion of rooflights, enlarged stair opening and reordering of the first-floor level. 29.

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. However, the uncertainty over effects of the internal alterations within the attic level relating to the removal of beams and provision of services to the bathroom mean that I am unable to determine that any consequent harm from these aspects of the proposal would also be outweighed by the public benefits. https://www.gov.uk/planning-inspectorate 5

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. However, the uncertainty over effects of the internal alterations within the attic level relating to the removal of beams and provision of services to the bathroom mean that I am unable to determine that any consequent harm from these aspects of the proposal would also be outweighed by the public benefits. https://www.gov.uk/planning-inspectorate 5

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. Appeal Decisions APP/J1915/W/25/3366883 & APP/J1915/Y/25/3366886 30. I have considered whether it would be possible to issue a split decision, permitting elements other than the alterations to the attic level comprising the removal of beams and installation of a bathroom. However, it seems to me that these would be an integral part of the proposed roof conversion such that they would not be clearly severable from the wider proposal in either appeal. I am not therefore satisfied that this approach would be possible or appropriate in this case. 31. Given the above, I conclude that the proposal would fail to preserve the special interest and significance of the Grade II* listed building Marden Hill House, Service Block and Annexe, and I am unable to determine that the collective harm would be outweighed by the public benefits. There is no clear and convincing justification for the proposal as a whole, and it would fail to satisfy the requirements of the LBCA Act and the Framework.

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. Although not determinative in the case of Appeal B, there would also be conflict with Policies HA1, HA7, HOU11 and DES4 of the East Herts District Plan 2018 insofar as they are relevant and broadly seek a high standard of design that respects or improves on the character of a site, alterations appropriate to dwellings, the preservation and enhancement of the historic environment and proposals that preserve historic fabric and do not adversely affect the architectural and historic character or appearance of a listed building. Other Matters 32. As well as identifying harm to the listed building, the Council’s reasons for refusal of both appeal applications suggest harm to the character and appearance of the surrounding area. This is not a relevant consideration in Appeal B which relates solely to effects on the listed building. In terms of Appeal A, the Council’s evidence does not provide any clear discussion of how harm would be caused to the character and appearance of the area. However, given my findings that the external changes to the building would preserve, or in the case of the replacement rooflight enhance, the listed building, I do not identify harm to the character and appearance of the surrounding area. 33.

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — to North elevation and a replacement rooflight window to South elevation’. The appeal site is within the Green Belt. I have no firm reason to disagree with the Council that the Appeal A proposal would not comprise inappropriate development and would not harm the openness of the Green Belt. However, this is not a factor that alters my assessment of the main issue. Conclusion 34. For the reasons given above, I conclude that the appeals should be dismissed.

Theresa's Cottage, Marden Hill, HERTFORD, SG14 2NE — East Hertfordshire District Council — J Bowyer INSPECTOR https://www.gov.uk/planning-inspectorate 6