Appeal 3275644

The appeal is allowed and planning permission is granted for demolition of existing flat roof extension attached to the south elevation and construction of a replacement extension beneath a pitched roof at [site address] , [address], Devoran [postcode] in accordance with the terms of the application, Ref PA20/06801, dated 12 August 2020, and the plans submitted with it, subject to the following conditions:

The development hereby permitted shall begin not later than 3 years from the date of this decision.

The development hereby permitted shall be carried out in accordance with the following approved plans: 1156/A3/01 – Location Plan; 1156/A3/02 – Site Plan as Existing; 1156/A3/03 – Ground Floor Plan as Existing; 1156/A3/04 – Elevations as Existing; 1156/A3/05A – Site Plan as Proposed; 1156/A3/06A – Ground Floor Plan as Proposed; 1156/A3/07B – Elevations as Proposed.

Development shall not proceed above damp-proof course level until details of the materials to be used in the construction of the external surfaces of the extension and pitched roofs hereby permitted have been submitted to and approved in writing by the local planning authority. Development shall be carried out in accordance with the approved details.

The Council’s reason for refusal refers to paragraphs 194, 196 and 200 of the National Planning Policy Framework 2019. After the decision, on 20 July 2021, the Government published its revised National Planning Policy Framework (the Framework). In the revised version the paragraphs are renumbered 200, 202 and 206, but otherwise remain unaltered. The appeal timetable has allowed both parties the opportunity to make comments relating to the updated Framework.

The main issue is whether the development would preserve or enhance the Outstanding Universal Value (the OUV) of the Cornwall and West Devon Mining Landscape World Heritage Site (the WHS), and the character or appearance of the Devoran Conservation Area (the CA).

The WHS was inscribed in 2006, and comprises ten areas across Cornwall and [name] that were heavily influenced by copper and tin mining in the period 1700 to 1914. The Statement of OUV states that the remains of mines, engine houses, smallholdings, ports, harbours, canals, railways, tramroads, and industries allied to mining, along with new towns and villages reflect an extended period of industrial expansion and prolific innovation. It adds that the ten areas form a unified, coherent cultural landscape and share a common identity.

Paragraph 189 of the Framework says that World Heritage Sites are heritage assets of the highest significance, which are internationally recognised to be of OUV. Policy 24 of the Cornwall Local Plan - [name] 2010-2030 (the Local Plan) and Policy HE1 of the Feock Neighbourhood Development Plan 2019 (the Neighbourhood Plan) both seek to ensure that developments do not have an adverse impact on the integrity of the WHS. These development plan policies align with the advice at paragraphs 199 and 200 of the Framework, which require great weight to be given to the conservation of heritage assets.

The WHS Management Plan 2020-2025 describes Devoran as an important copper mining port, dating from the late 1820s and 1830s, at the lower end of the once heavily industrialised Carnon Valley, and at the southern terminus of the Redruth & [name] (1824). The description goes on to say that, although its wooden wharf has largely disappeared, there are the remains of ore-storage bins, granite mooring-bollards and various former port buildings, now in private use. The Council contends that the reference to former port buildings covers [site address] , and that it is, therefore, an attribute that contributes to the OUV of the WHS.

However, the appellant’s research indicates that the building already existed as a dwelling prior to the emergence of Devoran as a mining port, and the formation of the adjacent tramway. Consequently, whilst it is common ground that the building was likely to have been used as an office associated with the tramway and quay, there is evidence that it was not originally constructed for these purposes. Furthermore, the evidence relating to the importance and longevity of its use in connection with the tramway and quay is inconclusive. Notwithstanding this uncertainty about the provenance of the original building, and its subsequent use, it has undergone significant rebuilding, alteration and extension since the Redruth & [name] closed in 1915.

The building that now exists comprises a simple, single-storey, rectangular core building with a ridged roof covered in concrete tiles and with a chimney stack at each gable. It has a large flat-roofed extension to its eastern end, which is set slightly back from the front elevation of the original building. There is also a flat-roofed extension on the south side, which covers approximately a third of the rear elevation of the core building. The walls of the whole building are rendered, and the windows, eaves, and rainwater goods are uPVC. It is entirely residential in character, with domestic scale window openings and surrounded by a garden. There is, therefore, little in its current appearance and character that provides any indication that it may once have been associated with the quayside activities related to the mining industry.

Although the building is located alongside the route of an historic tramline that was integral to mining operations, the documentary evidence of its importance to the quayside activities is inconclusive. In any event, the building has subsequently been altered and extended such that its current appearance and character do not provide any visual indication that it may once have played a significant role in the activities of the historic port. Consequently, the existing building makes little contribution to the OUV of the WHS.

The building also lies in the CA. I have not been provided with a [name] describing the special interest of this heritage asset, but from my own observations, its significance is derived from the layout of the settlement resulting from its emergence as a mining port; the surviving historic buildings and quayside features from that era; and its scenic landscape setting overlooking [name]. The building is set outside the main planned core of the village, and has little visual association with the surviving quayside artefacts that signal the past history of the settlement. The relatively recent, and extensive alterations and extensions mean that it does not retain any overt historic character. Consequently, whilst it sits comfortably alongside the line of the old tramway, it does not make a notable contribution to the significance of the CA.

Section 72(1) of the Planning (Listed Buildings and Conservation Areas) Act 1990 requires me to pay special attention to the desirability of preserving or enhancing the character or appearance of the CA.

The building is identified by the Neighbourhood Plan as being on an Undesignated Local Heritage List, where it is described as a “Cottage, [name] building” dating from pre-1840. Policy HE1 of the Neighbourhood Plan says that development should not have an adverse impact on locally designated sites of historic interest. Paragraph 203 of the Framework advises that, in weighing applications that directly or indirectly affect non-designated heritage assets, a balanced judgement will be required having regard to the scale of any harm or loss and the significance of the heritage asset.

The proposal involves the removal of the existing flat-roofed extension on the rear elevation, and its replacement with a wider extension. It would have a ridged roof running parallel to that of the core building. Consequently, it would be a significantly larger structure that would cover a greater part of the southern elevation of the original building. However, this elevation is only readily visible from the footpath to the south of the site. From here it is not seen in juxtaposition with the old tramway, or any of the historic buildings in the CA. Rather, it is seen in relative isolation, and the existing flat-roofed additions, modern roofing materials, and assortment of uPVC doors and windows means that this elevation displays little in the way of historic character or architectural quality. The proposed extension would be constructed in matching materials, with window openings of similar proportions to those in the existing extension. Consequently, it would not result in a significant change to the character of the dwelling from this viewpoint.

The rear of the dwelling can also be glimpsed from the quayside, to the east of the listed [name]. However, from here, it is partially screened by vegetation, and is seen beyond the glazed swimming pool enclosure in the intervening garden of a dwelling in the foreground. The mundane rear elevation of the dwelling does not provide any obvious visual or functional connection with the surviving remnants of the historic quayside activities. Viewed from here, the proposed extension would not, therefore, result in any harm to the setting of the listed buildings, the OUV of the WHS, or the character of the CA.

The proposal also includes the provision of pitched roofs over the flat roofed extensions on the eastern side of the building. It is contended that, in combination with the replacement extension to the rear, the legibility of the original building would be harmed. However, the ridges of both elements would be lower than that of the original building, so would not compete for visual dominance. Furthermore, the rear extension, albeit wider, would still be set in from the gable ends, allowing for a significant expanse of the original roof slope to be visible in southerly views. The rear extension would become visible from the [address] to the north, due to its increased height. However, its roof would be visually separated from the main building, with a lower ridge, so when approaching from the west, the gable end of the core building would remain the dominant feature, and the original roof form would still be readily discernible.

In easterly approaches, the proposed pitched roofs over the existing flat-roofed extension would conceal part of the gable of the core building. However, the ridges would be lower, and set further back than that of the main roof. Consequently, notwithstanding that the extensive rebuilding, extension and alteration of the original building has shorn it of any significant architectural or historic interest, its scale and form would remain legible. Furthermore, evidence of its past functional relationship with the old tramway would be unaffected by the rear extension or the pitched roofs, so any remaining contribution that the building makes to the OUV of the WHS would be preserved.

I therefore conclude that the development would preserve the OUV of the WHS, the character and appearance of the CA, and the significance of the non-designated heritage asset. Consequently, the proposal would accord with Policy 24 of the Local Plan, Policy HE1 of the Neighbourhood Plan and the guidance contained in the WHS Management Plan 2020-2025 and the WHS Supplementary Planning Document (2017). In combination, these seek to protect, conserve and, where appropriate, enhance the significance of these designated and non-designated assets. The proposal would also meet the Framework’s aim to conserve and enhance the historic environment.

In accordance with the legislation, I have imposed a condition limiting the period within which the development must commence. I have also included a condition specifying the relevant plans, as this provides certainty. The Council has suggested a condition requiring the submission of details of the timber cladding to be used on the extension. However, the submitted drawings indicate that the extension would be rendered. I have therefore imposed a condition requiring all external materials to be submitted for approval, in the interests of preserving the character and appearance of the non-designated heritage asset, and its consequent contribution to the CA and the OUV of the WHS.

For the reasons given above, I conclude that the appeal should be allowed.