Planning application
51 Upper Montagu Street London W1H 1FQ
Works: Extension Windows or glazing
Permission granted. Work must normally begin within three years of the decision or the permission lapses.
Proposal
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.
As published by the council, reference 25/03875/LBC
Application record
- Reference
- 25/03875/LBC
- Type
- Listed Building Consent Application
- Status
- Decided
- Decision
- Application Permitted
- Received
- 9 Jun 2025
- Validated
- 9 Jun 2025
- Decided
- 6 Oct 2025
- Ward
- Marylebone
- Decision by
- Complex 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.
-
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).
-
26/00814/ADLBC Granted
51 Upper Montagu Street London W1H 1FQ
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)
-
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
-
9 Jun 2025
Received by Westminster
-
6 Oct 2025
Decision issued: Application Permitted
-
30 Aug 2026
Added to PlanIndex
Related applications
Cases linked to this one on the register
1 later application on the register refers to this one:
-
26/00814/ADLBC Granted
51 Upper Montagu Street London W1H 1FQ
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)
Who's behind it
Company information only, from the register and Companies House
Agent on file, a planning consultancy
44 applications on PlanIndex · across 5 councils · 100% granted
Trade members see who it is, their full track record, and every application they have filed.
See who's behind itDocuments
Plans, drawings, consultee responses and the officer's report
37 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 this grant of permission means
Westminster granted permission on 6 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 heritage and listed building applications
Listed building consent is needed for works that affect the special interest of a listed building, and carrying out such works without it is a criminal offence. More in our guide to planning application types.
Nearby applications
Within 500 metres
-
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 -
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
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)
Granted Conditions Windows or glazing 12 docs -
57A Upper Montagu Street London W1H 1SG
90% historically approved · decision due ~1 Apr
Replacement of two windows on the rear elevation with timber double-glazed sash windows.
Awaiting decision Heritage and listed buildings Windows or glazing 14 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
Other heritage and listed building applications
In Westminster
-
26/06025/LBC Awaiting decision
House Of Commons Palace Of Westminster Parliament Square London SW1A 0AA
Installation of new and replacement electronic equipment within Speaker. (Linked with 26/06024/FULL)
-
26/05971/LBC Awaiting decision
House Of Commons Palace Of Westminster Parliament Square London SW1A 0AA
Automation of door at principal floor level.
-
26/05962/LBC Awaiting decision
Royal Albert Hall Kensington Gore London SW7 2AP
Variation of condition 2 of listed building consent dated 26 March 2024 (RN: 24/00820/LBC) for the: Erect temporary access scaffolding platform at high level in the auditorium to inspect the condition of the plaster ceilings and main cornices. NAMELY, to allow the gantry to remain in place until December 2028.
-
26/05970/LBC Awaiting decision
Norman Shaw Building South Victoria Embankment London SW1A 2HZ
Replacement and installation of 16 electronic access control systems to Norman Shaw South
-
26/05943/LBC Awaiting decision
1 Barton Street London SW1P 3NG
Use of the building as F1(a) Education, along with associated internal and external alterations. (Linked with 26/05942/FULL)