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Lakeside Mental Health Unit, West Middlesex Hospital, Twickenham Road, Isleworth, TW7 6AF

P/2026/0117PF-Full ApplicationsApproved
Full

Approved on 23 April 2026

Approximate site (title boundary)
Boundary © HM Land Registry, © Ordnance Survey · details

This information is subject to Crown copyright and database rights 2026 and is reproduced with the permission of HM Land Registry. The polygons (including the associated geometry, namely x, y co-ordinates) are subject to Crown copyright and database rights 2026 Ordnance Survey AC0000851063. Conditions of use.

Proposal

Alterations to the external elevations to allow installation of safety windows and doors at the main entrance, new external fencing and new external plant (HVAC) compound for new mental health crisis assessment centre (MHCAS) to part of the ground floor of Lakeside Mental Health Centre

Received
14 January 2026
Ward
Syon & Brentford Lock
  1. Received14 Jan
  2. Validated26 Feb
  3. Consult.25 Mar
  4. Target
  5. Decided23 Apr

Decided in 56 days (council typically 56)

About this application

This is a full planning application for window replacement at Lakeside Mental Health Unit, West Middlesex Hospital, Twickenham Road, Isleworth, TW7 6AF. Hounslow has handled 2,372 applications of this type. This one was decided in 99 days, 6 weeks longer than Hounslow's typical decision time. There are no previous applications recorded at this address. In the past year there have been 88 applications across Syon & Brentford Lock. We hold 894 applications in total for the TW7 postcode area.

76% of full applications at London Borough of Hounslow were approved. Across all application types, the council typically decides in about 8 weeks (median).

Based on decided applications received in the last 3 years.See what's approved near your address

Application details

Postcode
TW7 6AF
Application type
PF-Full Applications
Scale / size
Small

Planning application dates

Date validated
26 February 2026
Consultation expiry
25 March 2026
Consultation start
4 March 2026
Consultation end
25 March 2026
Application expires
23 April 2026

Planning decision

Statutory period
56 days

Additional information

Documents
9

Site constraints

Checking the site
2/3
Council recordsAppealsFlood risk

Designations that overlap or adjoin the site outline.

  • Article 4 direction: Dwellinghouses (C3) to small HMOs (C4) - borough-wide Article 4 Direction
  • Flood zone 1: Low probability (rivers and sea)

Possibly incomplete for this council: tree preservation orders.

Also checked, none recorded (22)

flood storage areas, conservation areas, listed buildings, 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.

Source: Hounslow

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

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