Planning application
Flat 2 New Cavendish Mansions 48 New Cavendish Street London W1G 8TG
Works: Windows or glazing
Still open. Anyone can comment while the consultation period runs, and comments go to the council rather than to us.
Proposal
Retrofit of existing windows, including insertion of slimline double-glazing windowpanes to front facade.
As published by the council, reference 26/00872/FULL
Application record
- Reference
- 26/00872/FULL
- Type
- Full Planning Permission Application
- Status
- Pending
- Received
- 12 Feb 2026
- Validated
- 12 Feb 2026
- Ward
- Marylebone
- Postcode
- W1G 8TG
Timeline
Dates from the published record
-
12 Feb 2026
Received by Westminster
-
21 Jul 2026
Added to PlanIndex
-
Decision
Awaiting decision
Decision expected by 9 April 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 65 days over the applications it decided in the last year.
Who's behind it
Company information only, from the register and Companies House
Howard de Walden Estates Limited Agent, a developer registered in London
Active · incorporated 1963 · London
35 applications on PlanIndex
Trade members see everything this firm has filed, how it was decided, and get an email the day it files again.
See their track recordDocuments
Plans, drawings, consultee responses and the officer's report
13 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.
Trade members open them from here.
Open the documentsWhat happens while it is decided
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 89 days. More in our guide to how long planning decisions take.
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.
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87% historically approved · decision due ~10 Jul
Alteration and improvement of existing heating and cooling to the Chapel through reinstatement of a working fan to dome, installation of fan coil units and an associated air source heat pump, removal of existing wall heating panels, and opening of fixed windows. (Linked to 26/03230/LBC)
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