Planning application
12 Chester Street London SW1X 7BB
Works: Extension Loft or dormer Windows or glazing
Permission granted. Work must normally begin within three years of the decision or the permission lapses.
Proposal
Amendment to planning permission dated 24th July 2025 (RN 24/05883/FULL) for the Excavation of a new basement level. Replacement of existing rear extension at first, second and third with a new rear extension (first to third floor level) with flat roof. Erection of an extension at rear ground floor level. Removal of the existing kitchen rooflight and extension of existing terrace at first floor level. Replacement of existing windows and French doors with new; NAMELY to amend the description of development to omit 'Excavation of a new basement level'; amended description of development to read as follows: 'Replacement of existing rear extension at first, second and third with a new rear extension (first to third floor level) with flat roof. Erection of an extension at rear ground floor level. Removal of the existing kitchen rooflight and extension of existing terrace at first floor level. Replacement of existing windows and French doors with new'.
As published by the council, reference 26/00535/NMA
Application record
- Reference
- 26/00535/NMA
- Type
- Non-material amendments
- Status
- Decided
- Decision
- Granted As published: Application Permitted
- Received
- 29 Jan 2026
- Validated
- 29 Jan 2026
- Decided
- 16 Mar 2026
- Ward
- Knightsbridge & Belgravia
- Decision by
- Delegated Decision
- Postcode
- SW1X 7BB
Site history
Applications at this address on the Westminster register
This site has had 5 applications since 2025: 3 approved, 0 refused.
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26/02886/LBC Awaiting decision
12 Chester Street London SW1X 7BB
Replacement of existing rear extension at first, second and third with a new rear extension (first to third floor level) with flat roof. Erection of an extension at rear ground floor level. Removal of the existing kitchen rooflight and extension of existing terrace at first floor level. Replacement of existing windows and French doors with new; and alterations to French door width at rear first floor level.
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26/01507/FULL Awaiting decision
12 Chester Street London SW1X 7BB
Variation of condition 1 of planning permission dated 24th July 2025 (RN 24/05883/FULL) for the Excavation of a new basement level. Replacement of existing rear extension at first, second and third with a new rear extension (first to third floor level) with flat roof. Erection of an extension at rear ground floor level. Removal of the existing kitchen rooflight and extension of existing terrace at first floor level. Replacement of existing windows and French doors with new. NAMELY, to omit the approved basement and minor amendments to the upper floors.
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25/09271/FULL Granted
12 Chester Street London SW1X 7BB
Installation of air conditioning units within an acoustic enclosure at roof level and replacement of the existing lead flat roof with a new lead flat roof.
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25/09272/LBC Granted
12 Chester Street London SW1X 7BB
Installation of air conditioning units within an acoustic enclosure at roof level and replacement of the existing lead flat roof with a new lead flat roof.
Timeline
Dates from the published record
-
29 Jan 2026
Received by Westminster
-
16 Mar 2026
Decision issued: Application Permitted
-
21 Jul 2026
Added to PlanIndex
Who's behind it
Company information only, from the register and Companies House
Thompson Planning Ltd Agent, a planning consultancy registered in Epping
Active · incorporated 2017 · Epping
4 applications on PlanIndex · across 4 councils
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
8 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 16 March 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 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
-
12 Chester Street London SW1X 7BB
Installation of air conditioning units within an acoustic enclosure at roof level and replacement of the existing lead flat roof with a new lead flat roof.
Granted Full applications 22 docs -
12 Chester Street London SW1X 7BB
Installation of air conditioning units within an acoustic enclosure at roof level and replacement of the existing lead flat roof with a new lead flat roof.
Granted Heritage and listed buildings 17 docs -
12 Chester Street London SW1X 7BB
90% historically approved · decision due ~26 Jun
Replacement of existing rear extension at first, second and third with a new rear extension (first to third floor level) with flat roof. Erection of an extension at rear ground floor level. Removal of the existing kitchen rooflight and extension of existing terrace at first floor level. Replacement of existing windows and French doors with new; and alterations to French door width at rear first floor level.
Awaiting decision Heritage and listed buildings Extension Loft or dormer +1 12 docs -
12 Chester Street London SW1X 7BB
88% historically approved · decision due ~4 May
Variation of condition 1 of planning permission dated 24th July 2025 (RN 24/05883/FULL) for the Excavation of a new basement level. Replacement of existing rear extension at first, second and third with a new rear extension (first to third floor level) with flat roof. Erection of an extension at rear ground floor level. Removal of the existing kitchen rooflight and extension of existing terrace at first floor level. Replacement of existing windows and French doors with new. NAMELY, to omit the approved basement and minor amendments to the upper floors.
Awaiting decision Full applications Extension Loft or dormer +1 17 docs -
24 Chester Street London SW1X 7BL
Erection of two storey rear extension at ground and lower ground floor level and associated works.
Granted Full applications Extension 41 docs -
24 Chester Street London SW1X 7BL
Erection of two storey rear extension at ground and lower ground floor level and associated works.
Granted Heritage and listed buildings Extension 34 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.