Planning application
25/05998/FULL
4 Mill Street London W1S 2AX
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
Timeline
Dates from the published record
-
22 Aug 2025
Received by Westminster
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5 Sep 2025
Validated
Checked as complete and ready for consideration.
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28 Oct 2025
Decision issued: Application Permitted
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21 Jul 2026
Added to PlanIndex
What a grant of permission means
The process from here
Permission has been granted, usually subject to conditions listed on the decision notice, some of which must be discharged before work starts. The decision notice on the council portal sets out exactly what was approved.
Work must normally begin within three years of the decision or the permission lapses. Neighbours cannot appeal a grant; challenging one means judicial review of how the decision was made, within tight time limits.
About full applications applications
How this application type works
A full application seeks permission for a complete, detailed proposal in one go: siting, design, access and landscaping are all fixed at this stage. It is the standard route for new buildings, conversions and changes of use. The statutory target is eight weeks for smaller schemes and thirteen weeks for major development, though complex cases often take longer by agreement.
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