Planning application
4 Mill Street London W1S 2AX
Works: New dwelling Extension Windows or glazing Several homes
Read from the description, not a valuation. How we read the register
Permission granted. Work must normally begin within three years of the decision or the permission lapses.
Proposal
Erection of a rear roof extension at third floor level with a sedum roof to the rear; replacement of windows at second floor level with double glazing timber windows; replacement of door and window to the existing rear first floor extension with double glazing timber windows including replacement of roofing; and associated works all in connection with the use of the first to third floor as four flats (Class C3)
As published by the council, reference 25/05998/FULL
Application record
- Reference
- 25/05998/FULL
- Type
- Full Planning Permission Application
- Status
- Decided
- Decision
- Granted As published: Application Permitted
- Received
- 22 Aug 2025
- Validated
- 5 Sep 2025
- Decided
- 28 Oct 2025
- Ward
- West End
- Decision by
- Delegated Decision
- Postcode
- W1S 2AX
Timeline
Dates from the published record
-
22 Aug 2025
Received by Westminster
-
5 Sep 2025
Validated
Checked as complete and ready for consideration.
-
28 Oct 2025
Decision issued: Application Permitted
-
21 Jul 2026
Added to PlanIndex
Who's behind it
Company information only, from the register and Companies House
4D Planning Agent, a planning consultancy
174 applications on PlanIndex · across 37 councils · 64% granted
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See their track recordDocuments
Plans, drawings, consultee responses and the officer's report
29 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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Open the documentsWhat this grant of permission means
Westminster granted permission on 28 October 2025, 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.
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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