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Flat 4 St Davids House 16 New Cavendish Street London W1G 8UP

26/01855/FULLFull Planning Permission ApplicationApproved
Full

Approved on 22 May 2026

Site boundary (council red line)

Proposal

Alterations to the uppermost storey of Flat 4, involving the removal of two existing rear dormers and the construction of a single replacement rear dormer, like-for-like replacement of existing roof terrace railings and decking, and internal alterations including the replacement of existing modern kitchen fittings and associated joinery. (Linked to 26/01857/LBC)

Received
23 March 2026
Ward
Marylebone
Agent
Bonnystreet (Town) Planning Limited
  1. Received23 Mar
  2. Validated23 Mar
  3. Consult.
  4. Target18 May
  5. Decided22 May

Decided in 60 days (council typically 49)

About this application

This is a full planning application for a dormer extension at Flat 4 St Davids House 16 New Cavendish Street London W1G 8UP. Westminster has handled 4,484 applications of this type. This one was decided in 60 days, 11 days longer than Westminster's typical decision time. The site is in the Harley Street conservation area, with 8 listed buildings nearby. There has been 1 other application at this address. In the past year there have been 171 applications across Marylebone. We hold 590 applications in total for the W1G postcode area.

86% of full applications at City of Westminster were approved. Across all application types, the council typically decides in about 7 weeks (median).

Based on decided applications received in the last 3 years.Planning something similar? See what gets approved on your street

Application details

Postcode
W1G 8UP
Application type
Full Planning Permission Application
Scale / size
Small

Planning application dates

Date validated
23 March 2026
Target decision date
18 May 2026

Applicant and agent

Agent
Bonnystreet (Town) Planning Limited
Agent address
41a Birdhurst Rise London CR2 7EJ United Kingdom

Planning decision

Statutory period
56 days

Additional information

Planning Portal ID
PP-14624036
Comments
0
Documents
17

Site constraints

Checking the site
2/3
Council recordsAppealsFlood risk

Designations that overlap or adjoin the site outline.

  • Conservation area: Harley Street
  • Listed building: Grade II: 14 and 16, New Cavendish Street W1On this site
  • Article 4 direction: Article 4 Basement Development Permitted Rights Removed+1 more
  • Flood zone 1: Low probability (rivers and sea)
Also checked, none recorded (21)

flood storage areas, tree preservation orders, green belt, scheduled monuments, World Heritage Sites, World Heritage Site buffer zones, registered parks and gardens, registered battlefields, Heritage at Risk entries, nutrient neutrality catchments, national parks, National Landscapes, SSSIs, Special Areas of Conservation, Special Protection Areas, Ramsar sites, ancient woodland, national nature reserves, local nature reserves, heritage coasts and brownfield registers.

A guide only, from official open data; it is not a planning search. Flood zones cover rivers and sea, not surface water.

Data © Crown copyright and others · sources and licences

Contains public sector information from planning.data.gov.uk (MHCLG and local planning authorities), licensed under the Open Government Licence v3.0. © Crown copyright and database right 2026.

© Historic England 2026. Contains Ordnance Survey data © Crown copyright and database right 2026. The Historic England GIS Data contained in this material was obtained on 2026-11-03. The most publicly available up to date Historic England GIS Data can be obtained from HistoricEngland.org.uk.

© Natural England copyright. Contains Ordnance Survey data © Crown copyright and database right 2026.

© Environment Agency copyright and/or database right 2026. All rights reserved. Flood Map for Planning, Open Government Licence v3.0.

Contains Ordnance Survey data © Crown copyright and database right 2026.

Source: Office for National Statistics licensed under the Open Government Licence v.3.0. Contains OS data © Crown copyright and database right 2026.

Associated applications

  1. 2026
    23 Mar

    Alterations to the uppermost storey of Flat 4, involving the removal of two existing rear dormers and the…

    This applicationApprovedFull26/01855/FULL
  2. 2026
    23 Mar

    Alterations to the uppermost storey of Flat 4, involving the removal of two existing rear dormers and the…

    ApprovedListed building consentPart of26/01857/LBC

Source: Westminster

Contains public sector information from the Planning London Datahub, licensed under the Open Government Licence v3.0.

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