Appeal 3359700

The appeal is allowed and planning permission is granted for a mansard roof extension at [site address] , Hackney, London [postcode] in accordance with the terms of the application, Ref 2024/2156, 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: 363_SL_01, 363_BL_01, 363_EX_01, 363_EX_02, 363_EX_03, 363_EX_04, 363_EX_05, 363_EX_06, 363_EX_07, 363_EX_08, 363_EX_09, 363_EX_10, 363_PR_01, 363_PR_02, 363_PR_03, 363_PR_04, 363_PR_05, 363_PR_06, 363_PR_07, 363_PR_08, 363_PR_09, 363_PR_10 and 363_PR_11.

The main issue is the effect of the proposal on the character and appearance of the host property, the terrace, and the area, including whether it would preserve or enhance the character or appearance of the [address] and Mapledene Conservation Area.

Section 72(1) of the Planning (Listed Buildings and Conservation Areas) Act 1990 states that, in respect of development affecting conservation areas, special attention shall be paid to the desirability of preserving or enhancing their character or appearance.

The site falls within the extensive [address] and Mapledene Conservation Area (‘the GRMCA’). I observed that whilst there is a range of property types and styles, many date from the Victorian period and are laid out in a fairly regular pattern of terraces or semi-detached pairs, and which display chimney stacks, ornamental brickwork, and sash windows typical of their era. The architectural quality of the buildings, the grain of development, and the setting amongst landscaping, and on often tree-lined roads, contribute to the significance of this designated heritage asset.

At pages 56 to 61 the [name] and Alterations Supplementary Planning Document 2009 (‘the HSPD’) provides guidance on mansard roof extensions. Paragraph 3.85 states that although some terraced houses were originally built with mansard roofs, the continuity of parapet lines is an important townscape feature of early/mid Victorian streets and is typical of the streetscene of large areas of Hackney. It continues that roof extensions are not normally acceptable in terraces where an unbroken roof line remains.

The host comprises a Victorian property, which sits within a fairly cohesive two storey terrace. The terrace is mostly finished in yellow stock brickwork, and its front face displays features typical of the era, including a regular pattern of sash windows, and a strong parapet line - although the parapet at Nos 14 and 16 is slightly stepped up, and lacks the cornice detailing of the others. The terrace undoubtedly makes a positive contribution to the GRMCA.

Whilst there are no mansard roofs in this terrace, the proposal would be set back behind the front parapet, and it would have a very shallow pitched front roof slope. It would also have low profile, flush fitting ‘conservation area’ type roof lights.

Consequently, it would not break the front parapet line; and, with reference to the proposed street section (drawing no. 363_PR_11), I am satisfied that it would be largely concealed in streetscene views from the opposite side of [address]. Whilst it may be slightly more visible when approaching along [address] from the east, that would be at a greater distance, and given its low profile, and the use of natural dark grey slate as recommended in the HSPD, it would not stand out as an incongruous feature.

From this terrace’s rear gardens, and from [address] to the west, the building’s mainly butterfly roof and its party parapet walls are clearly visible. However, the rear of the building is plainer than its front face, and there is some variety of form, as No [address] with a small extension, and No 16 does not have a butterfly roof. In that context, whilst the proposed mansard and the raised yellow brick parapet walls would be clearly visible, they would not appear out of place, particularly given their materials; and the timber sash windows, which would align with, but be slightly smaller than, those in the floor beneath.

Having regard to the evidence at [name] of the appellant’s statement, this mansard would be less bulky, with a much shallower front roof, and thus much more discrete, compared to a previous proposal which was dismissed at appeal.

For the above reasons, the scheme would not harm the character and appearance of the host property, the terrace, or the area. Having regard to the special duty contained in Section 72(1) of the Act, the significance of the GRMCA would be preserved.

The scheme would not therefore conflict with Policies LP1 and LP3 of the Hackney Local Plan 2033 (2020), or with Policies D4 and HC1 of the London Plan (2021). In general terms, these require the highest architectural and urban design quality, which responds to local character and context; and which preserves or enhances the historic environment, including the character or appearance of conservation areas, having regard to matters such as height, massing, scale, form, design, materials and detailing. Neither would it conflict with the thrust of the advice in the HSPD.

Turning to the matter of conditions, I have considered those suggested by the Council against the tests in the National Planning Policy Framework 2024. As well as the standard time limit, in the interests of certainty, a condition is necessary requiring that the development be carried out in accordance with the approved plans. Those plans clearly specify the proposed facing materials.

For these reasons, and having regard to all other matters raised, the appeal is allowed.