Appeal Decisions

Hearing held on 2 September 2025 Site visit made on 3 September 2025 Hearing closed on 26 September 2025

by F Cullen BA(Hons) MSc DipTP MRTPI IHBC

an Inspector appointed by the Secretary of State

Decision date: 02 February 2026

Appeal A Ref: APP/X5210/W/25/3363713

8 Gloucester Gate, Camden, London NW1 4HG

• 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 [APPELLANT] against the decision of the Council of the London Borough of Camden.
• The application Ref is 2024/3349/P.
• The development proposed is various alterations to dwelling house and mews including replacement of the rear extension, rebuilding of mews roof, internal refurbishment consisting of demolition and reposition of some partition walls and other associated works.

Appeal B Ref: APP/X5210/Y/25/3363714

8 Gloucester Gate, Camden, London NW1 4HG

• 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 [APPELLANT] against the decision of the Council of the London Borough of Camden.
• The application Ref is 2024/3387/L.
• The works proposed are various alterations to dwelling house and mews including replacement of the rear, closet wing extension, rebuilding of mews roof, internal refurbishment consisting of demolition and reposition of some partition walls and other associated works.

Decisions

1. Appeal A: The appeal is dismissed.
2. Appeal B: The appeal is dismissed.

Preliminary Matters

3. The two appeals concern the same scheme under different, complementary legislation. I have dealt with both appeals together in my reasoning.
4. As part of the appeals, the appellants submitted addendum documents and two revised plans which did not form part of the applications and were not considered or consulted on by the Council in its decisions [1]. Having regard to guidance [2] and caselaw [3] concerning late evidence and amendments to schemes in the appeal process, the documents merely provide additional information in support of the 1 Documents: Fireplace Addendum and Energy and Overheating Addendum; and Revised Plans: 030001 Rev 02 Proposed - Lower Ground Floor Plan; and 030007 Rev 02 Proposed - Lower Ground Floor RCP (Para 5.31.1 of Appellants’ Statement of Case). 2 Section 16: Procedural Guide: Planning Appeals – England. Dated 9 December 2025. 3 Holborn Studios Ltd v The Council of the London Borough of Hackney (2018), which refined the ‘Wheatcroft principles’ set out in Bernard Wheatcroft v Secretary of State for the Environment (1982). appellants’ case; and the revised plans comprise a single, small change to the layout of the proposed ensuite in the front room at basement level. In addition, the Council and any interested parties have had the opportunity to comment on these documents and plans as part of the appeals and hearing process. Given the above, as confirmed at the hearing, I exceptionally accept them and have taken them into account in the determination of the appeals.
5. At the hearing, the Council submitted an additional document, titled ‘Sustainability’ with five short attachments [4]. The document supports the Council’s case in relation to its fifth reason for refusal on Application Ref: 2024/3349/P. In addition, the appellants were given the time and opportunity to consider and respond to the document at the hearing. As a result, I exceptionally accept the sustainability document and have taken it into account in the determination of the appeals.
6. The proposal involves the partial demolition of a Grade I listed building. At the hearing the Council confirmed that the Georgian Group (the GG) had not been notified [5]. To ensure procedural correctness and without prejudice, it was requested that the Council give notice of the application for listed building consent to the GG.
7. The event proceeded on 2 September 2025, but was not closed on that day and instead kept open to allow the notification period of 21 days to run. The GG responded to the notification with comments on 18 September 2025. The appellants were then given the opportunity to respond, and did so on 23 September
8. Following this, the hearing was formally closed in writing on 26 September
9. For the avoidance of doubt, I have taken the GG’s comments and any responses from the parties into account in my determination of the appeals.
10. The Council has published the Camden Local Plan Proposed Submission Draft for consultation, which ran from 1 May to the 27 June 2025. The parties agree that the Submission Draft is now a material consideration in the determination of planning applications/ appeals, but that the relevant emerging policies, namely D1, D4 and D5 in relation to design and heritage, and CC8 in relation to overheating and cooling, have limited weight at this stage. I have no reason to take a different view.
11. The appeal scheme (the scheme) comprises several elements of development and works. The Council’s reasons for refusal on heritage grounds focus on specific matters in relation to these. Additionally, the signed and agreed Statement of Common Ground (SOCG) sets out the parties’ respective positions regarding any finding of harm to the significance of the listed building and conservation area as a result of the scheme. The elements where one or both parties identify harm include: demolition of existing closet wing; replacement annex; internal alterations to main house (basement level-creation of an ensuite in front room, ground floor levelopening between front and rear principal rooms, second floor level-reversal of the upper secondary staircase/ opening up of the blind arch/ ‘squaring off’ the principal front room, roof level-rooflight to replace dormer, and replacement of chimneypieces [6]); and alteration of the mews building (opening of blind arches and rooflight). 4 Including extracts from relevant local development plan policies (adopted and emerging); extracts from relevant national and local guidance; and a comparison of the original and addendum dynamic thermal modelling reports. 5 As required under ARRANGEMENTS FOR HANDLING HERITAGE APPLICATIONS – NOTIFICATION TO HISTORIC ENGLAND AND NATIONAL AMENITY SOCIETIES AND THE SECRETARY OF STATE (ENGLAND) DIRECTION 2021. 6 Also referred to in the evidence as fireplaces.
12. It is common ground between the parties that, with the exception of those elements cited above, all other aspects of the development and/or works proposed are acceptable in conservation terms, subject to conditions where necessary. In exercising the relevant statutory duties, and being mindful of submitted representations [7], from the written and oral evidence presented, I have no reason to disagree with the conclusions of the main parties’ in this regard. I find that the uncontested elements of development and works would preserve the special interest of the listed building and the character and appearance of the conservation area, and would not harm the significance of these designated heritage assets.
13. Consequently, for the avoidance of doubt, I have focused my considerations on the elements of the scheme where harm to significance has been identified.
14. The Council’s reasons for refusal 1-3 on Application Ref: 2024/3349/P cite perceived effects on the ‘setting of adjacent Grade I listed buildings’. Whilst there are other listed buildings located nearby [8], the Council confirmed prior to the hearing that this is in reference to other properties within the same ‘listed building’ of which the appeal property forms part.

Main Issues

13. Having regard to the above and as agreed at the hearing, the main issues are:

• Whether the proposal would (i) preserve the Grade I listed building known as Numbers 2 to 11 and attached railings, or its setting or any features of special architectural or historic interest which it possesses; and (ii) preserve or enhance the character or appearance of the Regent’s Park Conservation Area (Appeals A and B).
• Whether the need for active cooling equipment as proposed has been satisfactorily demonstrated, having regard to the application of the London Plan cooling hierarchy (Appeal A).

Reasons

Listed building and conservation area

Special interest and significance 14. The appeal site (the site) comprises No. 8 Gloucester Gate (No 8), including the main house, closet wing extension, and associated mews building. It forms part of a Grade I listed building, Numbers 2 to 11 and attached railings (Nos 2-11)[9], a designated heritage asset of the highest significance, which is positioned on the north-eastern side of Regent’s Park. 15. The terrace of Nos 2-11 was designed by John Nash, and was one of the last terraces to be constructed as part of his development of the Regent’s Park Estate. The listed building comprises 10 individual units, set out over three or four storeys, with attics and basements. The interiors are stated not to be the work of Nash. 16. With regard to No 8, the appellants’ evidence sets out what is perceived to be the property’s phased evolution, with the main house dated as circa 1827; the early 7 Regent’s Park Conservation Area Advisory Committee. 8 Paragraph 4.48 of the Appellants’ Planning and Heritage Statement, Montagu Evans, dated August 2024. 9 National Heritage List for England, List Entry Number: 1078322. closet wing extension dated as circa 1835-1872; and the mews building dated as circa 1835. These three components of the property have been the subject of external and/or internal alteration over time, with the most recent notable change being in 1987, when the property was converted from flats back to a single dwelling which included, amongst other changes, the extension of the closet wing. 17. Whilst the historic alterations to No 8 have compromised the listed building’s heritage interests to a degree, the main house retains some historic fabric, features of interest and internal planform; and the changes have largely respected the form, design, materials and hierarchy of the property’s component parts. 18. From the evidence before me, the special interest and significance of the listed building are largely derived from its exemplification of ‘First Rate’ early-19th century domestic architecture and urban planning, associated with one of the country’s most prominent architects of that period. The imposing grandeur of its harmonious palatial stucco frontage, contrasts with the plainer, more varied and altered, stock brick rear elevation, closet wings and associated mews buildings. It possesses group value as a terrace, but also as an integral component of a consciously planned development. The immediate and wider built and natural surroundings within which Nos 2-11 is experienced, also contributes positively to the building’s heritage merit. 19. With regard to No 8, important contributors in the above respects which are pertinent to the appeals, are the property’s surviving historic fabric; the status differentiation between the primary front and secondary rear facades; the architectural, functional and social hierarchy between its component parts as well as between the floors and rooms/spaces within them; the legibility of its historic internal planform; and its immediate rear courtyard setting which provides space within which to appreciate the relationship between its component parts. 20. The site is also located within the Regent’s Park Conservation Area (the CA), which encompasses, what is described in the Council’s Regent’s Park Conservation Area Appraisal and Management Strategy, 2011 (the CA A&MS) as, a ‘unique planned composition of landscape and buildings, at once classical and picturesque.’ The area has a strong sense of place, which is highly significant in conservation terms. 21. Relevant to the appeals, the impressive form and harmonious composition and materials of the principal facades of the Nash terraces, which are perceptible in views from public routes and spaces, are central to the distinctive character and appearance of the CA. In addition, and notwithstanding their sometimes concealed nature, the contrasting unadorned and more varied form of the terraces’ rear elevations and associated mews buildings, which provide an insight into the functional and social arrangement of the properties, are also notable features of the CA. 22. In exemplifying these key qualities, Nos 2-11 supports and contributes positively to the character and appearance of the CA as a whole and thereby to its significance as a designated heritage asset. Proposal and effects 23. Sections 16(2) and 66(1) of the Planning (Listed Buildings and Conservation Areas) Act 1990 (as amended) (the Act) require special regard to be had to the desirability of preserving the listed building or its setting or any features of special architectural or historic interest which it possesses; and section 72(1) of the Act requires special attention to be paid to the desirability of preserving or enhancing the character or appearance of the conservation area. 24. Additionally, when considering the impact of a proposed development on the significance of a designated heritage asset, Paragraph 212 of the National Planning Policy Framework (the Framework) requires that great weight should be given to the asset’s conservation (and the more important the asset, the greater the weight should be). Paragraph 213 goes on to state that, significance can be harmed or lost through the asset’s alteration or destruction or from development within its setting and that this should have clear and convincing justification. 25. The demolition of the existing closet wing would result in the irreversible loss of historic fabric and the evidential value which it holds, in displaying an early phase of No 8’s evolution as well as the physical, functional and social hierarchy of its component parts. Mindful of the secondary nature of the building’s rear elevation and extensions, as well as the historic changes to them over time, the potential exists for the closet wing to be replaced, provided that any new structure responds appropriately to its context which is highly sensitive to change. 26. The replacement annex’s detailed form has been arrived at through a comprehensive and iterative design process. It would align with a granted but unimplemented 1980s plan; be of a similar height to the existing closet wing and others on the terrace; result in a relatively modest increase in internal floor area and volume [10]; and be of high quality in terms of its construction and materials. 27. Nonetheless, historically, closet wing extensions are physically and functionally an ancillary component of a traditional townhouse. The replacement annex’s bowed profile with regular fenestration and detailing would run counter to this structure’s traditional orthogonal form, high solid to void ratio, and ad hoc character. Moreover, the replacement annex’s distinct shape and materiality would give it a prominence and presence that would weaken the status differentiation between the building’s front and rear elevations, as well as the hierarchy of its component parts. 28. These harmful effects to the building’s heritage interests would be compounded by the scheme’s intention to give the annex ‘functional importance’ making it the ‘heart of the home’[11]. Whilst this may take pressure off the more historically important spaces, it would also disrupt the relationship between the principal main house and associated ancillary structures. 29. In the above respects, the replacement annex would not be deferential to the host building. It would harmfully alter the authenticity of how the main house and mews building are experienced, particularly from within their immediate setting of the rear courtyard, altering the ability to appreciate their heritage merit. 30. I acknowledge that bows are a feature found in Neo Classical architecture, and note this form is present as part of the closet wing of No 7 Gloucester Gate and the infill extension at No 10 Gloucester Gate (No 10) granted permission and consent in 2016. Nonetheless, from the evidence before me and my observations on site, these are exceptions to the strong context of orthogonal closet wing/ rear 10 Page 12, Design Statement of Case, Dowen Farmer Architects, dated March 2025: GIA 634sqm / 6825sqft [+2.5%] Volume 2,055m3 [+2.5%]. 11 Page 18, Design & Access Statement, Dowen Farmer Architects dated July 2024. extensions to other townhouses on Nos 2-11 and in the area. I deal with No 10 further under other matters below. 31. In the front room at basement level, the revised proposal does not incorporate a partition wall directly abutting the chimneybreast. Nonetheless, it remains that the insertion of an en-suite and creation of a new doorway into the room would alter the historic proportions of, and access into, the space, as well as result in the loss of historic fabric, albeit limited. 32. However, reflecting its subordinate function, the spaces at basement level are of a more modest, cellular character, with fewer features of interest and detailing when compared with the principal floors of the house. Moreover, the evidence indicates that this level has been the subject of historic alteration. Taken together, this results in the basement being less sensitive to change than other floors. I am satisfied that this element of the scheme would preserve the special interest of the listed building, the detail of which had I been minded to allow the appeals, could have been secured by condition. 33. At ground floor level, the creation of a double width opening between the front and rear principal rooms would result in the loss of historic fabric, and the alteration of the historic circulation between these main spaces on this important floor. That said, the extent of lost fabric would be minimal and the historic proportions of the rooms would be maintained and legible, particularly when the doors are closed. Given the limited nature of this change and the proposed detailing which, had I been minded to allow the appeals, could have been secured by condition, I am satisfied that this element of the scheme would preserve the special interest of the listed building. 34. At second floor level, the contested elements of the scheme comprise the associated reversal of the upper secondary staircase, the opening up of the blind arch, and ‘squaring off’ of the principal front room. The appellants submit that, on the north side of the terrace, it was historically more common for secondary staircases to follow the configuration proposed (present in Nos 9 and 10) and that some staircases and/or planform at this level have been modified (as shown in Nos 5, 6 and 11). Investigations confirm that, with the exception of the newel post, the secondary staircase, infill within the arch, and a partition in the front room are of modern fabric and so, of negligible historic interest. In addition, the historic proportions of the front room at this level have been compromised to a degree by previous changes. 35. Even so, the earliest available plans for No 8 show the upper secondary staircase in its existing configuration, with the appellants’ evidence stating that ‘the internal planform of the main house….appears to have remained relatively intact by this time.’[12] The evidence presented does not demonstrate historic uniformity of the properties within the terrace at this level in staircase configuration or planform. Furthermore, there is no compelling evidence before me which supports the premise that these works would be ‘reinstating’ a historically recognisable configuration in this particular property [13]. 36. I therefore find that these works would undermine the authenticity and legibility of the building’s historic planform. The harm to significance at this level arising from 12 Figures 3.10-11 and Para 3.42 in Planning and Heritage Statement, Montagu Evans dated August 2024. 13 Page 11, Design Statement of Case, Dower Farmer Architects dated March 2025. alterations to planform is acknowledged by the appellants [14]. That these alterations would lead to an improved composition in terms of circulation and proportions at second and third floor levels does not clearly justify the harm to this aspect of the building’s identified heritage interests. 37. At roof level, toplighting of the main stairwell is proposed through the replacement of an existing dormer with a rooflight. Toplighting in this location is already provided by the dormer, which is stated to be a 20th century addition and of minimal heritage interest. The installation of a rooflight in this location would, essentially, maintain the current situation. Moreover, the loss of historic fabric, if any, would likely be limited. I am satisfied that this element of the scheme would preserve the special interest of the listed building, the detail of which had I been minded to allow the appeals, could have been secured by condition. 38. Taking into account my observations on site, I have no reason to dispute the findings of the detailed study and analysis of the chimneypieces within the property, which conclude that the majority are modern reproductions using poor quality materials and craftsmanship [15]. 39. On this basis, I am satisfied that, with the exception of the chimneypiece in the rear room on the third floor which is proposed to be retained, the removal and replacement of the modern replica chimneypieces would preserve the special interest of the listed building, subject to the appropriateness of any replacements. 40. On that matter, I acknowledge the reasons advanced in support of the chosen replacements set out under ‘selections per floor’ in the addendum report. However, having regard to the archival and current day images presented, I am not convinced that the proposed alternatives are fully appropriate to the age and character of the listed building. Nonetheless, had I been minded to allow the appeals, I am satisfied that this detail could have been secured by condition. 41. In relation to the mews building, the Council’s evidence refers to the blind Roman arches having been opened up in the past, but that they were blocked up again as part of the 1987 refurbishment. On this basis, the infill fabric within them is of negligible historic interest. 42. The existing and historic situation of the arches being blocked is indicative of the ancillary nature and subordinate function of the mews building in relation to the main house, providing quality of detail but also maintaining the social and functional hierarchy between the property’s component parts. Indeed, the CA A&MS identifies that Gloucester Gate mews buildings retain a real sense of their past function. 43. The opening up would not involve the loss of historic fabric; would retain the profile of the arches; and would improve the visual connection and permeability between the property’s component parts. I also note the Diocletian windows in arches of adjacent mews buildings and that this type of alteration was accepted as part of the granted scheme at No 10. However, the alteration would weaken the historic integrity of the mews building and fundamentally disrupt the historic relationship between it and the main house, eroding the listed building’s heritage interests. 44. The proposed rooflight in the mews building would be of a substantial size, extending across practically the whole width of the structure’s roof pitch. Without 14 Page 4 Summary Assessment Planning and Heritage Statement; and Paragraph 5.41.3 Expert Heritage Report. Montagu Evans. 15 Fireplace Report by Jamb.and Fireplace Addendum by Goddard & Studio. any evidence to the contrary, this would likely result in the loss of a sizeable amount of historic fabric. Moreover, its form would be overtly contemporary, jarring with the traditional features and character of the rest of this component part of the property. 45. Whilst I have found that there are elements of the proposal which, subject to condition, would preserve the special interest of the listed building, there are also elements that would markedly weaken the asset’s intrinsic heritage merit and would not conserve it in a manner appropriate to its significance. 46. The harmful effects would be to the rear aspect and the interior of No 8. Moreover, those alterations to the rear would be largely contained within the space between the main house and the mews building, and, as such, would be mainly limited to private views from adjacent properties and the, generally, private space of the cobbled mews. 47. As a result, many key aspects of the CA’s character and appearance would not be affected by the proposed scheme. Nevertheless, the harmful external changes at the rear of the listed building would undermine the heritage interests of an integral element of the CA, which supports and reinforces some of the key qualities of the area. It therefore follows that there would be some residual harm to the area, and the character and appearance of the CA as a whole would not be preserved. 48. Drawing all of the above together, I find that there are elements of the proposed development and works that would fail to preserve the Grade I listed building known as Numbers 2 to 11 and attached railings, or its setting or any features of special architectural or historic interest which it possesses. There are also elements that would fail to preserve or enhance the character and appearance of the Regent’s Park Conservation Area. This would be contrary to the requirements of sections 16(2), 66(1) and 72(1) of the Act. As such, there would be harm to the significance of these designated heritage assets. Public benefits, heritage balance and conclusion on heritage matters 49. In finding harm to the significance of a designated heritage asset, the Framework and Planning Practice Guidance (the PPG) require the magnitude of that harm to be expressed. 50. I have had regard to the fairly localised nature and extent of the harm, the intrinsic value of the elements affected by the scheme, and the degree of historic alteration, to No 8 and the listed building as a whole. I also acknowledge the appellants’ submission that the harm has been minimised through the detailed design process. Nonetheless, the status of the building as a designated heritage asset of the highest significance, results in it being more sensitive to change. I find that the harm to the significance of the listed building would be a moderate level of less than substantial. Given the listed building’s important contribution to the character and appearance of the CA, of itself and as part of a group, but also aware of the location and extent of the scheme, I find that the harm to the significance of the CA would be at the low end of less than substantial. These harms are of considerable importance and weight. 51. The appellants’ advance that, in balancing the proposed scheme’s perceived heritage benefits against the identified harm to significance, the harm would be outweighed and there would be a net positive impact on the listed building. 52. Nonetheless, neither the Act, Framework nor settled caselaw direct decision makers to carry out a ‘net’ or ‘internal’ balance of heritage-related benefits and harm as a self-contained exercise prior to a wider public benefit assessment as per the Framework. I have found harm to the significance of designated heritage assets as set out above, therefore the requirement to carry out a balance as prescribed in the Framework is engaged. 53. Paragraph 215 of the Framework requires a finding of ‘less than substantial harm’ to be weighed against the public benefits of the proposal including, where appropriate, securing the asset’s optimum viable use. 54. Having regard to guidance in the PPG as to what is meant by the term public benefits [16], there would be a number of heritage benefits arising from the scheme that would undoubtedly be positive. These would accrue from the removal of inappropriate modern and/or low-quality fabric; and the appropriate replacement, refurbishment and/or reinstatement of features within the building to a high scholarly standard. Of themselves, these would sustain and enhance the significance of the listed building and the CA within which it sits, and contribute to their long-term conservation. 55. There would be some economic benefits generated by the investment into the property in the, time limited, construction/refurbishment phase using professional expertise. Environmental benefits would also accrue from the landscaping within the site; and improvements in the environmental performance of the site with a predicted 16.3% reduction in carbon emissions. The latter is primarily due to the replacement annex, and is considerably greater than other scenarios tested. 56. Collectively, I find that the public benefits which would accrue from the scheme carry moderate weight in favour of the appeals. 57. Even so, some of the outcomes of the scheme would primarily be of private benefit to any occupier of the property, such as additional accommodation, general improvements to the layout of and circulation within the property, and the permeability between its main component parts. Moreover, high quality in design and construction is a requirement of good conservation planning. These factors, therefore, weigh neither for nor against the appeals. 58. Additionally, whilst I have considered the scheme as a whole, I am mindful that many of the heritage benefits identified are not contingent on the implementation of the parts of the scheme which I have found would cause harm to the significance of the listed building and conservation area. 59. With respect to the environmental benefits, I am cognisant that Paragraph 167 of the Framework requires significant weight to be given to the need to support energy efficiency improvements to existing buildings. However, in the context of these appeals, policies regarding the conservation and enhancement of the historic environment should also be applied. 60. I note the contents of Advice Note 18 published by Historic England (HE)[17] which supports adapting historic buildings for energy and carbon efficiency. Nonetheless, the guidance is clear that questions of scale and balance are important. Whilst it is 16 Planning Practice Guidance, Paragraph: 020 Reference ID: 18a-020-20190723. 17 Adapting Historic Buildings for Energy and Carbon Efficiency, Historic England Advice Note 18 dated July 2024. reasonable to conclude that the predicted environmental gains would be ‘meaningful’, the impact on the significance of the assets would not be ‘minimal’.[18] 61. I recognise the limitations of 21st century living in the existing property and acknowledge the appellants’ desire to adapt the property to their needs, in terms of its existing accommodation, layout, circulation and facilities. However, I am not persuaded that the only way of accruing some or all of the public benefits advanced is by way of the particular scheme proposed. As such, clear and convincing justification has not been provided for the identified harm to significance. Furthermore, no substantive evidence has been put before me which verifies that the property would not be useable or viable as a dwelling, or that the long-term future and conservation of the listed building as a whole would be at risk if the appeals were to fail and the proposal, as submitted, was not implemented. Therefore, I am not convinced that the development and works, as proposed, are necessary to secure the listed building’s optimum viable use. 62. Whilst I give moderate weight to the identified public benefits, this is not sufficient to outweigh the considerable importance and weight I attach to the identified harm to the significance of the designated heritage assets. 63. Accordingly, I conclude that the proposal would fail to preserve the Grade I listed building known as Numbers 2 to 11 and attached railings, or its setting or any features of special architectural or historic interest which it possesses, and would fail to preserve or enhance the character and appearance of the Regent’s Park Conservation Area. There would be harm to the significance of these designated heritage assets which would not be outweighed by the public benefits accruing from the scheme. The proposal would therefore fail to satisfy the requirements of sections 16(2), 66(1) and 72(1) of the Act and the provisions within the Framework which seek to conserve and enhance the historic environment. 64. It would also conflict with Policy HC1 of the London Plan, 2021 (the London Plan) and Policies D1 and D2 of the Camden Local Plan, 2017 (the Local Plan) in so far as they require development proposals to preserve, conserve and where appropriate enhance the significance of heritage assets. Whether the need for active cooling equipment as proposed has been satisfactorily demonstrated 65. Part B of Policy SI 4 of the London Plan sets out a ‘cooling hierarchy’[19]. Whilst this part of the policy applies to major developments, supporting text states that the principles can also be applied to minor development. This approach is reflected in Policy CC2 of the Local Plan; and Camden Planning Guidance: Energy Efficiency and Adaptation, 2021 (CPG EE&A). 66. Policy CC2 requires development to be resilient to climate change and adopt appropriate climate change adaptation measures. Relevant to Appeal A, this includes part d. measures to reduce the impact of urban and dwelling overheating, including application of the cooling hierarchy; and part e. ensuring development 18 Paragraph 71, Adapting Historic Buildings for Energy and Carbon Efficiency, Historic England Advice Note 18 dated July 2024 19 Policy SI 4 of the London Plan Cooling Hierarchy 1) reduce the amount of heat entering a building through orientation, shading, high albedo materials, fenestration, insulation and the provision of green infrastructure; 2) minimise internal heat generation through energy efficient design; 3) manage the heat within the building through exposed internal thermal mass and high ceilings; 4) provide passive ventilation; 5) provide mechanical ventilation; and 6) provide active cooling systems. schemes demonstrate how adaptation measures and sustainable development principles have been incorporated into the design and proposed implementation. 67. Supporting text to Policy CC2 sets out that all new developments will be expected to submit a statement demonstrating how the London Plan’s ‘cooling hierarchy’ has informed the building design. Any development that is likely to be at risk of overheating will be required to complete dynamic thermal modelling to demonstrate that any risk of overheating has been mitigated. It goes on to state that, active cooling (air conditioning) will only be permitted where dynamic thermal modelling demonstrates there is a clear need for it after all of the preferred measures are incorporated in line with the cooling hierarchy. 68. The Camden cooling hierarchy reflects that in the London Plan and includes: minimise internal heat generation through energy efficient design; reduce the amount of heat entering a building in summer through orientation, shading, albedo, fenestration, insulation and green roofs and walls; manage the heat within the building through exposed internal thermal mass and high ceilings; passive ventilation; mechanical ventilation; and active cooling. 69. The CPG EE&A provides guidance in terms of the application of the cooling hierarchy and also confirms, if active cooling is unavoidable, the cooling requirement and details of the efficiency of the system need to be provided. 70. The appellants’ Energy and Overheating Risk Assessment (July 2024) and Energy and Overheating Risk Assessment Addendum (April 2025) detail the dynamic thermal modelling undertaken and application of the cooling hierarchy in relation to No 8. The 2024 report assesses the main house, replacement annex [20] and the mews building, and the 2025 report relates only to the main house. 71. The 2024 report concludes that, to achieve full compliance with the Chartered Institution of Building Services Engineers Technical Memorandum 59 (CIBSE TM59)[21] overheating risk criteria under the DSY1 weather scenario, active cooling is required to be installed in the master bedroom, bedrooms 2, 3, 4, 5, and reception room of the main house. Additionally, as a future-proofing measure in cases of extreme warmer conditions as portrayed by DSY2&3 weather scenarios, active cooling would be beneficial in the study and kitchen of the replacement annex; and the activity room of the mews building. 72. The ventilation services layout plans submitted as part of the applications/ appeals show that active cooling (Fan Coil Units) is proposed in the master bedroom, bedrooms 2, 3, 4, and reception room of the main house; and in the activity room of the mews building. 73. The crux of the Council’s case on this issue is that the passive cooling measures explored have only been considered individually and not in combination, which may further reduce the cooling demand and/ or eliminate the overheating risks; and that some of the measures have been discounted without being fully explored. 74. However, in terms of policy context and application of the cooling hierarchy, I am mindful that the site comprises an existing property where many of the considerations/ measures to be assessed are already fixed. The main component of ‘new development’ is the replacement annex where there is more scope to 20 Referred to in the reports as the Closet Wing. 21 TM59 Design methodology for the assessment of overheating risk in homes (2017). integrate energy efficient measures into the design, but from the plans there is no active cooling proposed in this component part. 75. Additionally, whilst I note the images presented and guidance cited by the Council, it is not unreasonable for the appellants to discount certain measures, such as external blinds/ shading, double-glazing and security grills, without detailed investigation due to the sensitivity of the site, a Grade I listed building within a conservation area. Indeed, any discussions with the Council on this matter would essentially be informal and would not guarantee the grant of some or all of these measures, singularly or in combination, at application stage. 76. The Council may wish that every scenario is modelled. However, it would seem to be a purposeless exercise to include and assess measures that, in all probability, would not be granted planning permission and/or listed building consent because of the constraints of the site. The results of the modelling and justification for the approach taken is clearly set out in the appellants’ evidence. 77. From the written and oral evidence presented, I am inclined to agree with the appellants that, by virtue of the listed status of Nos 2-11, combined with matters of noise and security, even when taken in combination, full compliance with CIBSE TM59 overheating risk criteria under the DSY1 weather scenario would not be achieved in the master bedroom, bedrooms 2, 3, 4, 5 and reception room in the main house. The need for active cooling within these spaces has therefore been satisfactorily demonstrated. Moreover, had I been minded to allow Appeal A, the cooling requirement and details of the efficiency of the system could have been secured by condition. 78. As the justification for active cooling in the mews building in the 2024 report was based on it being ‘beneficial as a future-proofing measure’, and it was not assessed further in the 2025 report, I find that the need for active cooling within this space has not been satisfactorily demonstrated. 79. Notwithstanding my conclusions above, I note that Paragraph 10.6 of the CPG EE&A states that active cooling is discouraged, unless the applicant can demonstrate exceptional circumstances where opportunities for cooling are unable to be controlled through passive measures alone. Whilst it does not elaborate on what constitutes ‘exceptional circumstances’, the sensitivity of the site in conservation and planning terms could be argued to be just that, particularly since the air conditioning proposed does not form part of the Council’s reasons for refusal on heritage grounds. 80. The Council raised concerns regarding precedent if the scheme was found to be compliant on this issue. However, each application and appeal must be determined on its individual planning merits. The demonstration of the need for active cooling in this instance are wholly specific to this property, site and proposal. 81. To conclude on this issue, having regard to the Grade I listed status of Nos 2-11 and the constraints of the site, in this instance, the need for active cooling equipment as proposed in the main house has been satisfactorily demonstrated, having regard to the application of the London Plan cooling hierarchy. In this respect, the proposal would comply with Policy CC2 of the Local Plan referred to above. 82. However, the need for active cooling equipment as proposed in the mews building has not been satisfactorily demonstrated, having regard to the application of the London Plan cooling hierarchy. In this respect the proposal would not comply with Policy CC2 of the Local Plan referred to above. 83. Nonetheless, a lack of harm in the above respect is a neutral consideration. Given my conclusions on the first main issue, it does not alter the outcome of the appeals.

Other Matters

84. The appellants have drawn my attention to a ‘similar form of development’ at No 10, which was granted planning permission and listed building consent by the Council in 2016 [22].
85. The principle of consistency in decision making is an important one. I acknowledge that there are similar elements in the granted scheme at No 10 and the scheme before me, primarily, the demolition of a mid/late 19th century closet wing, the two storey, bowed and contemporary form of its replacement; and the opening up of blind arches to the mews building.
86. That said, each decision turns on the facts and circumstances of that particular case at the time of the application. The officer report for No 10 concludes that, as the two storey extension between the house and mews did not form part of ‘the first or key phase of the development of the property’ and had been ‘heavily altered’, its significance was low and its demolition acceptable, subject to the design of the replacement.
87. From the information provided, the extent and nature of the closet wing’s heavy alteration are not clear. Additionally, the officer report suggests that it was taller than its replacement and impacted on arches within the mews building. As such, I cannot be certain that the baseline for assessing the scheme at No 10 is the same as that before me. Importantly, unlike No 10 where the Council did not identify any harm to significance, as part of the appeal scheme, the appellants have acknowledged that harm would arise from the demolition of the early closet wing and the opening up of the blind arches in the mews building. There are also distinct differences in the detailed design of the granted scheme and the scheme before me.
88. That HE did not comment on the appeal scheme[23], in contrast to its response to the scheme at No 10 [24], does not denote a lack of harm. It is also evident that in relation to No 10, whilst authorisation was given to the Council to determine those applications as it saw fit, HE maintained its view that the proportions and architectural form of the closet wing’s replacement would result in harm to the significance of the asset. As set out above, I share those conclusions in relation to this scheme. I also note the GG’s finding of less than substantial harm to the significance of no.8 Gloucester Gate which would not be outweighed by the proposed public (including heritage) benefits. 22 Application Refs: 2016/4064/L and 2016/3706/P, No 10 Gloucester Gate10 Gloucester Gate 2016/3706/P – External alterations to dwelling house and mews building (Class C3) including demolition and replacement of the two storey rear extension and other external works. Approved 16/12/2016; and 2016/4064/L – Various alterations to dwelling house and mews including replacement of the rear extension, mews roof rebuilt and alterations to fenestration, internal refurbishment consisting of demolition and reposition of some partition walls and other internal alterations. Approved 19/12/2016. 23 Providing a letter of authorisation dated 22 August 2024. 24 Pre App response dated 7 June 2016; and Application responses dated 18 August 2016 and 7 November 2016.
89. Additionally, the decisions cited date from 2016 and are prior to the adoption of the Local Plan in 2017 and the relevant policies contained within them referred to above.
90. A scheme at No 12 Gloucester Gate and Nos 12 & 13 Gloucester Gate Mews, which was allowed on appeal in May 2024, is also cited by the appellants [25]. However, that scheme did not involve the demolition (in whole or in part) of an existing closet wing extension, and the form, design and materials of the allowed glazed link are not comparable to the appeals before me.
91. Consequently, the details of the granted schemes further along the terrace and/or the context of their determination are not directly comparable and do not indicate that the scheme before me should be allowed.
92. The site is in proximity to a number of other Grade I, Grade II* and Grade II listed buildings [26]. From the information before me and my observations on site, the special interest and significance of these assets primarily stem from their historic and architectural interest. However, they are also derived, to a greater or lesser extent, from their respective 19th century planned urban settings.
93. Given the location and extent of the proposed scheme, I find that the settings of these listed buildings would be preserved and their significance would not be harmed. This would meet the requirements of section 66(1) of the Act; the provisions in the Framework regarding the conservation and enhancement of the historic environment; and Policy HC1 of the London Plan and Policy D2 of the Local Plan, referred to above. Nonetheless, a lack of harm in relation to these designated heritage assets is a neutral consideration and does not alter my conclusion on the first main issue.

Conclusions

94. Appeal A: The proposed development conflicts with the development plan. The material considerations do not indicate that a decision should be made other than in accordance with the development plan. Therefore, for the reasons given above, Appeal A should be dismissed.
95. Appeal B: For the reasons given above, Appeal B should be dismissed.

F Cullen

INSPECTOR 25 Appeal Decisions: APP/X5210/W/23/3331072 and APP/X5210/Y/23/3331076 Gloucester Lodge, 12 Gloucester Gate and 12 & 13 Gloucester Gate Mews, London NW1 4HG. Erection of glazed link connecting 12 Gloucester Gate and 12 and 13 Gloucester Gate Mews and associated works. Allowed 31 May 2024. 26Section 4.48 of the Appellants’ Planning and Heritage Statement, Monatgu Evans, dated August 2024.

APPEARANCES

FOR THE APPELLANTS: Tim Miles Montagu Evans Dr Timur Tatlioglu Montagu Evans Ben Clark Montagu Evans James Dowen Dowen Farmer Architects Sam Goddard Goddard & Studio Tom King XCO2 FOR THE LOCAL PLANNING AUTHORITY: Adam Greenhalgh Senior Planning Officer David McKinstry Principal Conservation Officer Chin Chin Lam Sustainability Officer

ADDITIONAL DOCUMENTS SUBMITTED PRIOR TO, AT, OR AFTER THE

HEARING

1. Policy HC1 of the London Plan, 2021.
2. Camden Planning Guidance: Energy Efficiency & Adaptation, 2021.
3. Appeal Decisions: APP/X5210/W/23/3331072 and APP/X5210/Y/23/3331076 Gloucester Lodge, 12 Gloucester Gate and 12 & 13 Gloucester Gate Mews, London NW1 4HG.
4. Council - Sustainability Document (comprising five attachments).
5. Historic England Guidance: Adapting Historic Buildings for Energy and Carbon Efficiency, Historic England Advice Note 18 (HEAN 18) (July 2024); The Setting of Heritage Assets, Historic Environment Good Practice Advice in Planning Note 3 (Second Edition) (December 2017); and Managing Significance in Decision-Taking in the Historic Environment, Historic Environment Good Practice Advice in Planning: 2 (July 2015).
6. Historic England Responses re 10 Gloucester Gate: Pre-application advice dated 7 June 2016; Consultation response dated 18 August 2016; and Consultation response to revised scheme dated 7 November 2016.
7. Final agreed and signed Statement of Common Ground received by PINS 18 September 2025.