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Planning application

12 Marylebone Mews London W1G 8PX

Refused Westminster 20/06911/FULL Full Planning Permission Application

Works: Loft or dormer Windows or glazing

Refused. Only the applicant can appeal, within the statutory time limit, and a revised scheme can be submitted instead.

Proposal

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

As published by the council, reference 20/06911/FULL

Application record

Reference
20/06911/FULL
Type
Full Planning Permission Application
Status
Decided
Decision
Application Refused
Received
30 Oct 2020
Validated
30 Oct 2020
Decided
21 Jan 2021
Ward
Marylebone High Street
Decision by
Delegated Decision
Postcode
W1G 8PX

Timeline

Dates from the published record

  1. 30 Oct 2020

    Received by Westminster

  2. 21 Jan 2021

    Decision issued: Application Refused

  3. 4 Sep 2026

    Added to PlanIndex

Who's behind it

Company information only, from the register and Companies House

Agent on file, an architecture practice

1 application on PlanIndex

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Documents

Plans, drawings, consultee responses and the officer's report

24 documents on file for this application

A planning file usually holds the application form, drawings and site plans, consultee responses, the officer's report and the decision notice.

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What this refusal means

Westminster refused this application for the reasons on the decision notice; only the applicant can appeal, and refused schemes often return in revised form. More in our guide to what happens after a planning decision.

About full applications

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.

Nearby applications

Within 500 metres

  • 11 Marylebone Mews London W1G 8PX

    26/00802/FULL Submitted 10 Feb 2026 9m away

    87% 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

  • 64 Wimpole Street London W1G 8YS

    26/01740/FULL Submitted 18 Mar 2026 37m away

    87% 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 38m 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 38m away

    87% 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

  • 58 Queen Anne Street London W1G 8HW

    25/08051/LBC Submitted 5 Nov 2025 43m away

    90% historically approved · decision due ~31 Dec

    Minor internal alterations to the building involving the introduction of double doors at ground floor level between the front and rear rooms.

    Awaiting decision Heritage and listed buildings 14 docs

  • 29 Welbeck Street London W1G 8DA

    08/03565/LBC Submitted 18 Apr 2008 45m away

    Glazed fire barrier at landing level in lieu of glazed fire corridor at third floor level and removal of partition at first floor level.

    Granted Heritage and listed buildings Windows or glazing 8 docs

In Westminster

  • 26/06024/FULL Awaiting decision

    House Of Commons Palace Of Westminster Parliament Square London SW1A 0AA

    Installation of new and replacement electronic equipment within Speaker. (Linked with 26/06025/LBC)

    3 Sep 2026 Full applications
  • 26/06017/FULL Awaiting decision

    38 Lauderdale Mansions Lauderdale Road London W9 1NE

    Installation of an external AC Unit / Heat Pump at roof level.

    2 Sep 2026 Full applications
  • 26/05938/FULL Awaiting decision

    24 Vincent Square London SW1P 2NJ

    Subdivision of existing residential property to create two self-contained 3-bedroom family homes, along with cycle parking and associated external alterations.

    1 Sep 2026 Full applications
  • 26/05935/FULL Awaiting decision

    47 Hereford Road London W2 5AH

    Installation of one number new external condenser unit to the southerly elevation service alley.

    1 Sep 2026 Full applications
  • 26/05959/FULL Awaiting decision

    Basement And Ground Floor 50 New Bond Street London W1S 1BJ

    Installation of three new condensers on the roof, within an existing designated plant area.

    1 Sep 2026 Full applications