Planning application
25/05866/FULL
Flat 1D Block 1 Portman Mansions Chiltern Street London W1U 5AJ
Proposal
Replacement of existing single-glazed timber sash and casement windows with double-glazed timber sash and casement windows to match the existing style and opening type. Existing window frames to be retained with no changes to the structural openings.
As published by the council, reference 25/05866/FULL
Timeline
Dates from the published record
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19 Aug 2025
Received by Westminster
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1 Sep 2025
Validated
Checked as complete and ready for consideration.
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17 Oct 2025
Decision issued: Application Refused
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21 Jul 2026
Added to PlanIndex
What refusal means
The process from here
The council refused this application for the reasons set out on the decision notice, which the council portal holds in full. Only the applicant can appeal a refusal; the time limit runs from the decision date and is shorter for householder schemes.
Refusal does not prevent a fresh attempt. Applicants often address the reasons for refusal and resubmit, so a refused scheme is not necessarily the end of proposals for the site.
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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