4 - 5 Cavendish Mews North London W1W 6LA

This site has had 4 applications since 2025: 4 approved, 0 refused.

• 26/00516/NMA Granted

  4 - 5 Cavendish Mews North London W1W 6LA

  Amendments to planning permission dated 12th June 2024 (RN 24/00473/FULL) for the erection of a roof extension and alterations to the front elevation to enlarge and alter residential dwelling (Class C3). NAMELY, roof extension reprofiling.

  Decided 30 Mar 2026 Amendments
• 25/08645/FULL Granted

  4 - 5 Cavendish Mews North London W1W 6LA

  Variation of condition 1 of planning permission dated 12 June 2024 (RN: 24/00473/FULL) for the: Erection of a roof extension and alterations to the front elevation to enlarge and alter residential dwelling (Class C3). Namely, to allow the installation of an air source heat pump within a roof level acoustic enclosure. (Application under section 73 of the Act).

  Decided 30 Mar 2026 Full applications
• 25/06141/NMA Granted

  4 - 5 Cavendish Mews North London W1W 6LA

  Amendments to planning permission dated 12th June 2024 (RN:24/00473/FULL) for Erection of a roof extension and alterations to the front elevation to enlarge and alter residential dwelling (Class C3) namely, the repositioning of windows to function as a skylight within the second floor mansard roof, the northernmost rooflight to be repositioned to serve as a secondary means of escape, the northernmost window at first floor level to be reconfigured to match the positioning of the existing surveyed windows and the omission of two rooflights.

  Decided 22 Sep 2025 Amendments

1. 19 Nov 2025

   Received by Westminster

2. 9 Mar 2026

   Decision issued: Application Permitted

3. 20 Aug 2026

   Added to PlanIndex

Westminster granted permission on 9 March 2026, subject to any conditions on the decision notice. Work must normally begin within three years or the permission lapses. More in our guide to what happens after a planning decision.

A full application seeks permission for a complete, detailed proposal in one go, with siting, design, access and landscaping all fixed at this stage. More in our guide to planning application types.

• Abercorn School 38 Portland Place London W1B 1LS

  26/00352/LBC Submitted 21 Jan 2026 50 yards away

  90% historically approved · decision due ~18 Mar

  Internal alterations to 38 Portland Place throughout to change the use from sui generis (Institutional Use) to Class E office use throughout in connection with removal of link building between 38 Portland Place and 9 Cavendish Mews North at ground, first and second floors, formation of a new rear stair core to main building and new external fire escape stair. New terraces to office space in connection with plant space and the installation of air source heat pumps. Alterations to the front and rear facades of the mews building in connection with internal alterations to create new residential units and new plant space to mews roof level and new terrace spaces all in connection with the change of use of ground to first floors from sui generis (institutional use) and second floor Class E (office use) of 9 Cavendish Mews North to Class C3 residential use to form 3x 1 bedroom flats. (Part of a land swap with 1 Marylebone High Street and Moxon House). (Linked to 26/00351/FULL)

  Awaiting decision Heritage and listed buildings New dwelling 61 docs

• Abercorn School 38 Portland Place London W1B 1LS

  26/00351/FULL Submitted 21 Jan 2026 50 yards away

  88% historically approved · decision due ~18 Mar

  Internal alterations to 38 Portland Place throughout to change the use from sui generis (Institutional Use) to Class E office use throughout in connection with removal of link building between 38 Portland Place and 9 Cavendish Mews North at ground, first and second floors, formation of a new rear stair core to main building and new external fire escape stair. New terraces to office space in connection with plant space and the installation of air source heat pumps. Alterations to the front and rear facades of the mews building in connection with internal alterations to create new residential units and new plant space to mews roof level and new terrace spaces all in connection with the change of use of ground to first floors from sui generis (institutional use) and second floor Class E (office use) of 9 Cavendish Mews North to Class C3 residential use to form 3x 1 bedroom flats. (Part of a land swap with 1 Marylebone High Street and Moxon House). (Linked to 26/00352/LBC)

  Awaiting decision Full applications New dwelling 85 docs

• 4 - 5 Cavendish Mews North London W1W 6LA

  26/00516/NMA Submitted 29 Jan 2026 50 yards away

  Amendments to planning permission dated 12th June 2024 (RN 24/00473/FULL) for the erection of a roof extension and alterations to the front elevation to enlarge and alter residential dwelling (Class C3). NAMELY, roof extension reprofiling.

  Granted Amendments Extension 15 docs
  Domestic

• 4 - 5 Cavendish Mews North London W1W 6LA

  25/06141/NMA Submitted 28 Aug 2025 50 yards away

  Amendments to planning permission dated 12th June 2024 (RN:24/00473/FULL) for Erection of a roof extension and alterations to the front elevation to enlarge and alter residential dwelling (Class C3) namely, the repositioning of windows to function as a skylight within the second floor mansard roof, the northernmost rooflight to be repositioned to serve as a secondary means of escape, the northernmost window at first floor level to be reconfigured to match the positioning of the existing surveyed windows and the omission of two rooflights.

  Granted Amendments Extension Loft or dormer +1 13 docs
  Domestic

• 4 - 5 Cavendish Mews North London W1W 6LA

  25/08645/FULL Submitted 26 Nov 2025 50 yards away

  Variation of condition 1 of planning permission dated 12 June 2024 (RN: 24/00473/FULL) for the: Erection of a roof extension and alterations to the front elevation to enlarge and alter residential dwelling (Class C3). Namely, to allow the installation of an air source heat pump within a roof level acoustic enclosure. (Application under section 73 of the Act).

  Granted Full applications Extension 13 docs
  Domestic

• 44 Portland Place London W1B 1NE

  23/03776/ADLBC Submitted 6 Jun 2023 50 yards away

  Details of new decorative plaster work/restoration works to existing decorative plaster work pursuant to Condition 5 (vii) of planning permission dated 08 February 2023 (RN:22/06619/LBC)

  Granted Conditions 12 docs

• 26/05984/FULL Decided

  41 Sutherland Street London SW1V 4JX

  Replacement of front, side and rear windows with double glazed timber framed sash windows and replacement of a door with a double glazed timber framed door.

  Received 2 Sep, published by the council 11 Sep 2026 Full applications
• 26/07229/FULL Awaiting decision

  5 D'arblay Street London W1F 8DL

  Painting of the shopfront facade and alterations to the existing fixed windows to form two openable sash windows. (Linked with 26/07230/ADV)

  Received 22 Oct, published by the council 26 Oct 2026 Full applications
• 26/07224/FULL Awaiting decision

  8 Hinde Street London W1U 3BQ

  Use of the building as an Embassy (sui generis) with reversion to Class E on cessation of occupation by the Government of the United Mexican States. Erection of a flagpole to front elevation.

  Received 22 Oct, published by the council 26 Oct 2026 Full applications
• 26/06134/FULL Decided

  Flat 10H Hyde Park Mansions Cabbell Street London NW1 5BG

  Replacement of front and rear second floor level windows with slim-profile double-glazed panels, retaining the existing window and door frames.

  Received 8 Sep, published by the council 15 Sep 2026 Full applications
• 26/07258/FULL Awaiting decision

  16A Croxley Road London W9 3HL

  Installation of air to air heat pumps to offices and bedrooms.

  Received 22 Oct, published by the council 23 Oct 2026 Full applications