Planning application
1 Marylebone High Street London W1U 4DL
Works: Extension Roofing Windows or glazing
Still open. Anyone can comment while the consultation period runs, and comments go to the council rather than to us.
Proposal
Amendments to planning permission dated 18 June 2025 (RN: 24/08179/FULL) for the: Rear extension to existing building, formation of new roof terrace including rooftop pavilion, new external plant, replacement of existing windows with double glazing and minor alterations to building facade including new entrance. Namely, to allow the removal of existing entrance step with a ramp; removal of existing smoke vents and pavement lights with concrete to match existing; and changes in window arrangement on rear and north elevation of the building.
As published by the council, reference 26/00431/NMA
Application record
- Reference
- 26/00431/NMA
- Type
- Non-material amendments
- Status
- Pending
- Received
- 26 Jan 2026
- Validated
- 30 Mar 2026
- Ward
- Marylebone
- Postcode
- W1U 4DL
Site history
Applications at this address on the Westminster register
This site has had 5 applications since 2025: 2 approved, 0 refused.
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26/05334/FULL Decided
1 Marylebone High Street London W1U 4DL
Removal of existing Luxcrete panelled pavement and replacement with York stone paving slabs outside 1 Marylebone High Street; and addition of textured porcelain tiles to office entrance step.
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25/08905/FULL Awaiting decision
1 Marylebone High Street London W1U 4DL
Use of the 1st and 2nd floor maisonette from residential use (Class C3) to office use (Class E). This application forms part of a land use swap with 38 Portland Place (inc. 9 Cavendish Mews North) and Moxon House
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25/06757/ADFULL Granted
1 Marylebone High Street London W1U 4DL
Detailed samples of the cladding for the rooftop pavilion pursuant to condition 4 of planning permission dated 18th June 2025 (RN: 24/08179).
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25/05396/ADFULL Granted
1 Marylebone High Street London W1U 4DL
Details of shopfront, new windows, new glazed entrance door, refuse & recycling storage, all flood resilient and resistant measures, elevation and floor plans showing privacy measures to prevent occupants of the terrace overlooking the roof terrace, pre-demolition audit and secure cycle storage for the ground floor retail units (two spaces) pursuant to conditions 8, 11, 15, 17, 20 and 21 of planning permission dated 18th June 2025 (RN:24/08179).
Timeline
Dates from the published record
-
26 Jan 2026
Received by Westminster
-
30 Mar 2026
Validated
Checked as complete and ready for consideration.
-
21 Jul 2026
Added to PlanIndex
-
Decision
Awaiting decision
Decision expected by 25 May 2026, 8 weeks from validation under the statutory target for most applications. Extensions of time are common and are agreed case by case.
Westminster took a median of 91 days over the applications it decided in the last year.
Who's behind it
Company information only, from the register and Companies House
Howard de Walden Estates Limited Agent, a developer registered in London
Active · incorporated 1963 · London
37 applications on PlanIndex · 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
18 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.
Watch members (£5 a month) open the document list from here.
Open the documentsWhat happens while it is decided
This application is with Westminster for determination, against a statutory target of eight weeks. Over the last year Westminster decided amendment applications in a median of 81 days. More in our guide to how long planning decisions take.
About amendment applications
An amendment application makes limited changes to a permission that already exists; anything beyond modest adjustment needs a fresh application. More in our guide to planning application types.
Nearby applications
Within 0.3 miles
-
1 Marylebone High Street London W1U 4DL
88% historically approved · decision due ~1 Oct
Removal of existing Luxcrete panelled pavement and replacement with York stone paving slabs outside 1 Marylebone High Street; and addition of textured porcelain tiles to office entrance step.
Decided Full applications -
1 Marylebone High Street London W1U 4DL
Detailed samples of the cladding for the rooftop pavilion pursuant to condition 4 of planning permission dated 18th June 2025 (RN: 24/08179).
Granted Full applications 8 docs -
1 Marylebone High Street London W1U 4DL
Details of shopfront, new windows, new glazed entrance door, refuse & recycling storage, all flood resilient and resistant measures, elevation and floor plans showing privacy measures to prevent occupants of the terrace overlooking the roof terrace, pre-demolition audit and secure cycle storage for the ground floor retail units (two spaces) pursuant to conditions 8, 11, 15, 17, 20 and 21 of planning permission dated 18th June 2025 (RN:24/08179).
Granted Full applications Demolition Windows or glazing 24 docs -
1 Marylebone High Street London W1U 4DL
88% historically approved · decision due ~2 Feb
Use of the 1st and 2nd floor maisonette from residential use (Class C3) to office use (Class E). This application forms part of a land use swap with 38 Portland Place (inc. 9 Cavendish Mews North) and Moxon House
Awaiting decision Full applications 14 docs -
120 Marylebone Lane London W1U 2QG
Details of bevelled glass pursuant to Condition 2 of planning permission dated 30 June 2005 (RN: 05/03306).
Granted Full applications 2 docs -
120 Marylebone Lane London W1U 2QG
Installation of new shopfront.
Granted Full applications Windows or glazing 7 docs
Other amendment applications
In Westminster
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26/07459/NMA Awaiting decision
1 Hanover Square London W1S 1HA
Amendments to planning pemrission dated 10 October 2025 (RN: 25/01558/FULL) for the: Partial demolition, refurbishment and extension of the existing building to provide a sub-basement, basement, ground plus eight storey building; infilling and stepped rear extension; excavation of a new sub-basement level; installation of new plant equipment at basement and roof level; terraces at fourth, fifth, sixth, seventh and eighth floor levels; soft and hard landscaping; reprovision of car parking; new cycle parking facilities; and associated external works. Use of the building for retail and/or restaurant (Class E) on part ground floor and office (Class E) on all other floors. NAMELY, to allow alterations to the design of the ground floor frontages on Hanover Square and St George Street.
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26/07438/NMA Awaiting decision
29 - 31 Hill Street London W1J 5LS
Amendments to planning permission dated 1st July 2025 (RN 25/01006/FULL) for the external alterations at roof level including the creation of Level 04 roof terrace for use in association with existing office (Class E), replacement and installation of new plant and landscaping, replacement of windows, introduction of louvres, removal and replacement of rooflights, installation of new rooflight and other associated works. NAMELY, for alterations comprising of the removal of window sash boxes and weights, changes to the window mullion arrangement, the removal of two sash windows, the installation of secondary glazing, the removal of existing chamber hatch and installation of extract vent and integrated bench, the external replacement of rainwater goods and hoppers, the removal of bricks and installation of airbricks, minor demolition works, replacement of roof covering, removal of ductwork, roof plant rearrangement, the installation of a new external door to plant area, minor layout alterations and other associated works.
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26/07389/NMA Decided
Flat 1 5 Grittleton Road London W9 2DD
Amendments to planning permission dated 04 June 2025 (RN: 25/02022/FULL), NAMELY, amendment of Condition 4 to correct the property address from 9 Aldridge Road Villas to Flat 1 5 Grittleton Road.
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26/07377/NMA Awaiting decision
60 Ledbury Road London W11 2AJ
Amendments to planning permission dated 2nd October 2025 (RN 25/04018/FULL) for the Partial demolition, refurbishment, and erection of a mansard roof extension to form a new third floor with dormers to front, side and rear elevations; to form 6 flats (Class C3) on upper floors; external plant equipment and ductwork; lower ground floor excavation to increase floor to ceiling height; replacement windows; cycle parking and associated external alterations; use of the part ground floor and lower ground floor as retail and restaurant (Class E). Site includes 60-68 Ledbury Road) NAMELY, An amendment to the basement and ground floor drawing reference numbers; amendment to the description of development, in reference to restaurant and or retail use; and amendments to C
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26/07375/NMA Awaiting decision
77 Hereford Road London W2 5BB
Amendments to planning permission dated 4th August 2026 (RN 26/03970/FULL) for the Replacement of roof terrace access stair with glazed hatch, new timber decking and front and rear roof railings to roof terrace, with infilling side window of closet wing. NAMELY, Hinged hatch access substituted by sliding hatch.