The Planning Sub-Committee (1) of Westminster City Council met on 11 November 2025, considering four planning applications. Permission was granted for alterations and a new basement at 4 Devonshire Close, and for a roof extension and other alterations at Hallam House, 56-60 Hallam Street and 44 and 50 Hallam Street. Permission was also granted for the installation of louvred doors at 55 Marylebone High Street, but an application for basement excavation at 5 Upper Belgrave Street was refused.

Planning Applications

5 Upper Belgrave Street

The committee unanimously refused conditional planning permission for the excavation of two basements, one beneath the main house and one beneath the mews house, with associated plant, addition of louvres to mews garage doors and internal works at 5 Upper Belgrave Street.

The application site is a six-storey Grade II* listed single family dwelling house linked to a three-storey unlisted mews building at the rear.

Objections to the application were received from neighbours, the Belgravia Residents' Association and the Belgravia Neighbourhood Forum on heritage, sustainability and amenity grounds, principally concerning the construction impacts of the proposed basement excavation.

4 Devonshire Close

Conditional planning permission was granted for substantial demolition of the building including the replacement of the front elevation and roof with the addition of solar panels, alterations to the fenestration to the front and rear elevations, and construction of a new basement level at 4 Devonshire Close.

The committee added three additional conditions to the permission:

• Prior to commencement of works to dismantle the front elevation and part rear elevation, details of the pre-demolition audit in accordance with section 4.6 of the GLA's adopted Circular Economy Statement guidance shall be submitted.
• You must apply to us for approval of a sample panel of brickwork, built on site, which shows the colour, texture, face bond and pointing.
• Notwithstanding the details shown on the approved drawings, the garage doors shall be made more traditional, in accordance with the adopted SPG, 'Mews: A Guide to Alterations' (vertical boarding, Collinge hinges, integral windows). The ground floor brickwork arches should be a splayed arch, not soldier.

The application site is a mid terrace residential mews property, likely dating from the late 18th century. The application sought its substantial demolition and redevelopment to provide a three-bedroom dwelling with basement. Objections had been received concerning the demolition of the building, sustainability, the inclusion of a basement, traffic and highways.

Hallam House, 56-60 Hallam Street, and 44 and 50 Hallam Street

The committee granted conditional planning permission and conditional listed building consent for the demolition of an existing roof plant room and erection of a single-floor roof extension to provide one residential unit, erection of a replacement plant room, and provision of an external terrace, landscaping and green roof, alterations to rear fenestration pattern, erection of single storey lower ground floor extension within rear lightwell to provide additional office floorspace and replacement of a window with a door at front ground floor level at Hallam House, 56-60 Hallam Street.

The committee also approved the extension of party wall and replacement of single chimney of front chimney stack of 44 and 50 Hallam Street to facilitate roof extension above 56-60 Hallam Street.

55 Marylebone High Street

Conditional planning permission was granted for the installation of louvred double doors and grille in the existing door and window openings on the rear of the building at ground floor level in association with a new electricity sub-station at 55 Marylebone High Street.

The application site is an unlisted building located within the Harley Street Conservation Area¹ and the Central Activities Zone². The building is occupied for uses within Class E³, with retail and restaurant uses.

Ward Councillor Barbara Azimov addressed the sub-committee in objection to the application.