Planning application
51 Upper Montagu Street London W1H 1FQ
Works: Windows or glazing
Relates to 25/03875/LBC
Permission granted. Work must normally begin within three years of the decision or the permission lapses.
Proposal
Detailed drawings of new doors, new windows including sections and glazing bar profiles, new skirting, and cornices, new fireplace surrounds, new Juliette balconies pursuant to condition 4 of listed building consent dated 28 October 2025 (RN: 25/03875/LBC)
As published by the council, reference 26/00814/ADLBC
Application record
- Reference
- 26/00814/ADLBC
- Type
- Approval of Details (ADLBC)
- Status
- Decided
- Decision
- Granted As published: Application Permitted
- Received
- 11 Feb 2026
- Validated
- 11 Feb 2026
- Decided
- 7 Apr 2026
- Ward
- Marylebone
- Decision by
- Delegated Decision
- Postcode
- W1H 1FQ
Site history
Applications at this address on the Westminster register
This site has had 4 applications since 2025: 3 approved, 0 refused.
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26/00898/ADFULL Awaiting decision
51 Upper Montagu Street London W1H 1FQ
Details of supplementary acoustic report, detailed drawings of all new doors and windows, new first floor balconettes and investigative report of Phase 1 pursuant to condition 5, 7, 8 and 11 (part) of planning permission dated 24 October 2025 (RN: 25/03874/FULL).
-
25/03875/LBC Granted
51 Upper Montagu Street London W1H 1FQ
Internal alterations including lowering of the floor level to the lower ground floor; Installation of replacement modern windows with slimline double-glazed units; external alterations to front and rear elevations to reinstate window baskets; installation of an air source heat pump and replacement of existing railings at main roof level; erection of the rear extension at lower ground floor level to include a green roof; and other associated works.
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25/03874/FULL Granted
51 Upper Montagu Street London W1H 1FQ
Internal alterations including lowering of the floor level to the lower ground floor; Installation of replacement modern windows with slimline double-glazed units; external alterations to front and rear elevations to reinstate window baskets; installation of an air source heat pump and replacement of existing railings at main roof level; erection of the rear extension at lower ground floor level to include a green roof; and other associated works.
Timeline
Dates from the published record
-
11 Feb 2026
Received by Westminster
-
7 Apr 2026
Decision issued: Application Permitted
-
21 Jul 2026
Added to PlanIndex
Related applications
Cases linked to this one on the register
-
25/03875/LBC Granted
51 Upper Montagu Street London W1H 1FQ
Internal alterations including lowering of the floor level to the lower ground floor; Installation of replacement modern windows with slimline double-glazed units; external alterations to front and rear elevations to reinstate window baskets; installation of an air source heat pump and replacement of existing railings at main roof level; erection of the rear extension at lower ground floor level to include a green roof; and other associated works.
Who's behind it
Company information only, from the register and Companies House
ADL Planning Pty Ltd Agent, a planning consultancy
101 applications on PlanIndex · across 7 councils · 91% granted
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
12 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 7 April 2026, 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 condition discharge and variation applications
This application deals with conditions on an existing permission, supplying the details a condition requires or asking to vary or remove one, without reopening the permission itself. More in our guide to planning application types.
Nearby applications
Within 0.3 miles
-
51 Upper Montagu Street London W1H 1FQ
87% historically approved · decision due ~9 Apr
Details of supplementary acoustic report, detailed drawings of all new doors and windows, new first floor balconettes and investigative report of Phase 1 pursuant to condition 5, 7, 8 and 11 (part) of planning permission dated 24 October 2025 (RN: 25/03874/FULL).
Awaiting decision Full applications Windows or glazing 11 docs -
51 Upper Montagu Street London W1H 1FQ
Internal alterations including lowering of the floor level to the lower ground floor; Installation of replacement modern windows with slimline double-glazed units; external alterations to front and rear elevations to reinstate window baskets; installation of an air source heat pump and replacement of existing railings at main roof level; erection of the rear extension at lower ground floor level to include a green roof; and other associated works.
Granted Heritage and listed buildings Extension Windows or glazing 37 docs -
51 Upper Montagu Street London W1H 1FQ
Internal alterations including lowering of the floor level to the lower ground floor; Installation of replacement modern windows with slimline double-glazed units; external alterations to front and rear elevations to reinstate window baskets; installation of an air source heat pump and replacement of existing railings at main roof level; erection of the rear extension at lower ground floor level to include a green roof; and other associated works.
Granted Full applications Extension Windows or glazing 36 docs -
53 Upper Montagu Street London W1H 1SE
Details of the height and finished appearance of the new openings at ground and second floor levels, and proposed remedial works required to address damp following inspection works pursuant to Condition 2 (parts i and ii) of the listed building consent dated 2 January 2025 (RN: 24/05972/LBC)
Granted Conditions 8 docs -
Flat 19 York House 39 Upper Montagu Street London W1H 1FR
Installation of double glazed steel casement windows within the retained existing timber frames to front and rear of Flat 19.
Granted Full applications Windows or glazing 25 docs -
56 Upper Montagu Street London W1H 1SN
90% historically approved · decision due ~18 Feb
Use of ground floor and mezzanine levels to rear as residential (Class C3) use; deconversion of ground floor and mezzanine levels to rear together with two studio flats and one one-bedroom flat to form one three-bedroom maisonette; creation of reconfigured office unit in basement; replacement of all but one window with slimline timber double glazed units installation of secondary glazing to one window; renovation of shopfront; reinstatement of glazed fanlight with opening vent, new solid panel door, and awning; new glazed doors to south elevation of mezzanine garden room; new metal balustrading across rear boundary and raised terrace surface level with walk-on roof lights; replacement of concrete roof tiles with slate and new glazed roof light/ roof access; creation of green roof above mezzanine garden room; removal of modern partition walls and reinstatement of historical plan form as far as possible; reinstatement of historic period features all in connection with the use of building as office at part basement level with the remainder of the building being used as a single residential unit (Class C3) and associated internal alterations. (Linked to 25/09342/FULL)
Awaiting decision Heritage and listed buildings New dwelling Loft or dormer +2 21 docs
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Details of external and internal signage strategy pursuant to Condition 7(E) of listed building consent dated 12th February 2021 (RN: 19/07816/LBC)
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26/04843/ADLBC Granted
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Detailed design and specification of new blinds to NZH based on mock-up trials on-site pursuant to Condition 6(m) of listed building consent dated 12th February 2021 (19/07816/LBC).
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Details of method statement for re-carving works pursuant to condition 3(i) of listed building consent dated 16 July 2026 (RN: 26/03399/LBC)
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26/04850/ADLBC Awaiting decision
17 Belgrave Square London SW1X 8PG
Detailed drawings of garage doors, roof lantern and any new lighting and flooring in the principal rooms pursuant to condition 6 (iii) (iv) (v) of listed building 18th August 2025 (RN:25/03417/LBC)
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25/07120/ADLBC Granted
72 - 74 Lancaster Gate London W2 3NH
Details of new and altered doors and door architraves, including external faces of lifts (detailed elevations and sections at 1:10) pursuant to Condition 3 (A) of Listed Building Consent dated 14 December 2023 (RN: 23/00772/LBC) (Linked app: 25/07088/ADFULL)