11 Marylebone Mews London W1G 8PX

This site has had 2 applications since 2026.

• 26/00802/FULL Awaiting decision

  11 Marylebone Mews London W1G 8PX

  Erection of a mansard roof extension, excavation and extension of the existing basement, installation of plant within a louvered acoustic enclosure on the rear flat roof at second floor and the replacement of the fenestration to the front and rear of the building; all to enlarge and alter dwellinghouse (Class C3).

  Submitted 10 Feb 2026 Full applications

1. 27 Oct 2026

   Received by Westminster

2. 2 Nov 2026

   Added to PlanIndex

3. Decision

   Awaiting decision

   Decision expected by 22 December 2026, 8 weeks from validation under the statutory target for most applications. Extensions of time are common and are agreed case by case.

   Westminster took a median of 88 days over the applications it decided in the last year.

• 26/00802/FULL Awaiting decision

  11 Marylebone Mews London W1G 8PX

  Erection of a mansard roof extension, excavation and extension of the existing basement, installation of plant within a louvered acoustic enclosure on the rear flat roof at second floor and the replacement of the fenestration to the front and rear of the building; all to enlarge and alter dwellinghouse (Class C3).

  Submitted 10 Feb 2026 Full applications

This application is with Westminster for determination, against a statutory target of eight weeks. Over the last year Westminster decided full applications in a median of 119 days. More in our guide to how long planning decisions take.

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.

• 11 Marylebone Mews London W1G 8PX

  26/00802/FULL Submitted 10 Feb 2026 50 yards away

  88% historically approved · decision due ~7 Apr

  Erection of a mansard roof extension, excavation and extension of the existing basement, installation of plant within a louvered acoustic enclosure on the rear flat roof at second floor and the replacement of the fenestration to the front and rear of the building; all to enlarge and alter dwellinghouse (Class C3).

  Awaiting decision Full applications Extension Loft or dormer +1 26 docs
  Domestic

• 12 Marylebone Mews London W1G 8PX

  20/06911/FULL Submitted 30 Oct 2020 50 yards away

  Installation of an acoustic enclosure containing two air conditioning condensers to rear of existing modern mansard roof and replacement window at rear roof level.

  Refused Full applications Loft or dormer Windows or glazing 24 docs

• 64 Wimpole Street London W1G 8YS

  26/01740/FULL Submitted 18 Mar 2026 50 yards away

  88% historically approved · decision due ~13 May

  Erection of a new roof terrace and green roof area at rear 2nd floor level; installation of plant and photovoltaic panels at main roof level and new mansard roof extension and installation of plant on the mews roof level; alterations at ground floor front elevation; Internal and external alterations throughout the building in connection with a rear elevation extension from first to fourth floor levels and the reconfiguration of the existing fifth floor level, installation of new double glazed windows throughout all in connection with a change of use to Class E (e) medical use.

  Awaiting decision Full applications Extension Loft or dormer +2 88 docs

• 4 Marylebone Mews London W1G 8PY

  26/04440/LBC Submitted 3 Jul 2026 50 yards away

  90% historically approved · decision due ~28 Aug

  Internal refurbishment including replacement of glazing to windows, clerestory, rooflights, entrance door and sidelights and minor external alterations. [Linked to 26/04439/FULL]

  Awaiting decision Heritage and listed buildings Loft or dormer Windows or glazing

• 4 Marylebone Mews London W1G 8PY

  26/04439/FULL Submitted 3 Jul 2026 50 yards away

  88% historically approved · decision due ~28 Aug

  Replacement of glazing to windows, clerestory, rooflights, entrance door and sidelights. [Linked to 26/04440/LBC]

  Awaiting decision Full applications Loft or dormer Windows or glazing

• 62 Wimpole Street London W1G 8AJ

  26/06523/FULL Submitted 23 Sep 2026 50 yards away

  88% historically approved · decision due ~18 Nov

  Alterations to the existing building to provide minor reconfiguration of plan form at lower ground, replacement and installation of external plant, installation of medi-sinks and WC, installation of secondary glazing, drylining and replacement of existing heating. (Linked to 26/06524/LBC)

  Awaiting decision Full applications Windows or glazing

• 26/06015/FULL Decided

  129 Saltram Crescent London W9 3JT

  Erection of a two-storey rear extension.

  Received 3 Sep, published by the council 11 Sep 2026 Full applications
• 26/05689/FULL Decided

  Flat 1 12 Bristol Gardens London W9 2JG

  Demolition of an existing conservatory at the rear at lower ground level and erection of single storey rear extension.

  Received 19 Aug, published by the council 14 Sep 2026 Full applications
• 26/07361/FULL Awaiting decision

  29 Alexander Street London W2 5NU

  Change of the existing ground and lower ground floors from Use Class E(g)(i) (Commercial business and service) to Class C3 dwelling with the creation of a two-bedroom maisonette with associated external alterations.

  Received 27 Oct, published by the council 2 Nov 2026 Full applications
• 26/07340/FULL Awaiting decision

  123 Victoria Street London SW1E 6DE

  Installation of a single-leaf glazed entrance door at ground level to the Victoria Street frontage

  Received 27 Oct, published by the council 30 Oct 2026 Full applications
• 26/07315/FULL Awaiting decision

  30 Inverness Terrace London W2 3JA

  Relocation of air conditioning units throughout to the lower ground floor lightwells within aluminium enclosure; replacement of all pipes with cast iron pipes; alteration to balconies including replacement of UPVC door with original door arrangement and replacement railing; reopening of previously infilled windows; replacement marble tiles at hallway of No.32 with Victorian floor tiles; replacement of all doors facing the communal staircase with the correct period style doors; removal of red clay tile leanto roof at first floor rear and the roof made good; removal of link bridges to the rear of the second floor and the rear of the third floor; and reopening of previously infilled windows to the stairs lobby at ground, first and second floor to No.30. (Linked with 26/07316/LBC)

  Received 26 Oct, published by the council 27 Oct 2026 Full applications