37 St Marys Grove, Chiswick, London, W4 3LN

1. 2 Oct 2025

   Received by Hounslow

2. 17 Nov 2025

   Decision issued: GRANT

3. 12 Aug 2026

   Added to PlanIndex

Permission has been granted, usually subject to conditions listed on the decision notice, some of which must be discharged before work starts. The decision notice on the council portal sets out exactly what was approved.

Work must normally begin within three years of the decision or the permission lapses. Neighbours cannot appeal a grant; challenging one means judicial review of how the decision was made, within tight time limits.

A lawful development certificate is a legal determination, not a planning judgement. It asks the council to confirm either that existing use or works are lawful, often through the passage of time, or that a proposal would not need planning permission at all. The applicant must prove the facts; the merits of the scheme are not considered.

More on lawful development applications in our guide

• 37 St Marys Grove, Chiswick, London, W4 3LN

  P/2025/3054 Submitted 10 Oct 2025 0m away

  Certificate of lawfulness for the proposed erection of two rear roof extensions with Juliet balconies, four front roof windows to the house and removal of chimney.

  Granted Lawful development Extension Windows or glazing 13 docs

• 63 Whitehall Park Road, Chiswick, London, W4 3NB

  P/2026/0116 Submitted 14 Jan 2026 56m away

  Variation of condition 2 (approved plans) to include parapet detail not shown on P/2025/0694 approved 29/04/2025 for the erection of single storey rear and infill extension to house.

  Granted Conditions Extension 8 docs
  Small domestic

• 51A ST MARYS GROVE, CHISWICK, LONDON, W4 3LW

  P/2021/2470 Submitted 18 Jun 2021 63m away

  Erection of a single storey outbuilding in the rear garden of the flat.

  Granted Full applications 7 docs
  Small domestic

• 51A ST MARYS GROVE, CHISWICK, LONDON, W4 3LW

  P/2021/2471 Submitted 18 Jun 2021 63m away

  Erection of a single storey rear/ side extension with roof alterations and associated works to the flat.

  Refused Full applications Extension Roofing 7 docs
  Small domestic

• 13 Gordon Road, Chiswick, London, W4 3LU

  P/2024/1853 Submitted 5 Jun 2024 67m away

  Ground floor side infill extension and rear extension.

  Granted Householder Extension 14 docs
  Domestic

• 59 St Marys Grove, Chiswick, London, W4 3LW

  P/2024/3403 Submitted 11 Oct 2024 88m away

  Erection of a rear roof extension to the house.

  Refused Householder Extension 18 docs
  Domestic

• P/2026/2033 Granted

  3 Benedict Drive, Feltham, TW14 8JH

  Certificate of lawfulness for the proposed erection of a rear roof extension with hip to gable conversion with windows to the front and side of the house.

  8 Jul 2026 Lawful development
• P/2026/2027 Granted

  115 Northumberland Crescent, Feltham, TW14 9SP

  Certificate of lawfulness for the proposed erection of a rear roof extension and windows to the front of the house.

  8 Jul 2026 Lawful development
• P/2026/2009 Granted

  3 Brainton Avenue, Feltham, TW14 0AZ

  Certificate of lawfulness for the proposed erection of a rear roof extension and Juliette balcony with front roof windows to the house.

  7 Jul 2026 Lawful development
• P/2026/2014 Granted

  82 Sussex Avenue, Isleworth, TW7 6LB

  Certificate of lawfulness for the proposed erection of a rear roof extension, a porch to the front of the house, and a front roof window.

  7 Jul 2026 Lawful development
• P/2026/2473 Awaiting decision

  16 Somerset Waye, Hounslow, TW5 9HG

  Certificate of lawfulness for the proposed erection of a rear roof extension with two roof windows to the front and alterations to the existing side roof from flat roof to pitched roof.

  1 Sep 2026 Lawful development