51 Park Avenue, Hounslow, TW3 2LY

1. 9 Jan 2026

   Received by Hounslow

2. 12 Aug 2026

   Added to PlanIndex

3. Decision

   Awaiting decision

   Decision expected by 6 March 2026, 8 weeks from validation under the statutory target for most applications. Extensions of time are common and are agreed case by case.

   Hounslow took a median of 55 days over the applications it decided in the last year.

This application is with Hounslow for determination. The council publicises it, consults neighbours and technical bodies where required, and weighs the responses against local and national planning policy.

The statutory target is eight weeks for most applications and thirteen for major development, though extensions of time are common. Comments carry most weight while the case is undecided, so check the council portal for the deadline if you want to respond.

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

• 133, Argyle Avenue, Hounslow, TW3 2LL

  PA26/1328 Submitted 15 Apr 2026 51m away

  P/2026/117 - Erection of a first floor side extension above the existing ground floor side extension.

  Granted Outline Extension 2 docs

• 44 Park Avenue, Hounslow TW3 2LX

  PA26/0488 Submitted 12 Feb 2026 70m away

  Lawful development certificate for the existing rear roof dormer, hip-to-gables and 4no. front rooflights.

  Granted Lawful development Loft or dormer 10 docs

• 80 ARGYLE AVENUE, HOUNSLOW, TW3 2LN

  PA/2023/0680 Submitted 2 Mar 2023 80m away

  Ground floor rear extension 6.00 metres deep, maximum height 2.95 metres, 2.95 metres high to the eaves

  Granted Prior approval Extension 6 docs

• 58 Wills Crescent Whitton Hounslow TW3 2JB

  21/1772/HOT Submitted 17 May 2021 85m away

  single storey side and rear extension following removal of existing side garage

  Granted Householder Extension 9 docs
  Small domestic

• 76 Argyle Avenue, Hounslow, TW3 2LN

  P/2026/1490 Submitted 18 May 2026 96m away

  Certificate of Lawfulness for the proposed erection of a rear roof extension, including a hip-to-gable roof conversion and installation of three front roof windows, erection of a front porch, and erection of a single-storey detached outbuilding in the rear garden.

  Granted Lawful development Extension Loft or dormer +1 11 docs
  Small domestic

• 76 Argyle Avenue, Hounslow, TW3 2LN

  PA/2026/1491 Submitted 18 May 2026 96m away

  Ground floor rear extension 6.00 metres deep, maximum height of 3.00 metres, 2.82 metres high to the eaves

  Granted Prior approval Extension 4 docs

• 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