8 Sidmouth Avenue, Isleworth, TW7 4DW

1. 13 Nov 2025

   Received by Hounslow

2. 6 Jan 2026

   Decision issued: GRANT

3. 12 Aug 2026

   Added to PlanIndex

Hounslow granted permission on 6 January 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.

A lawful development certificate is a legal determination that existing or proposed works do not need planning permission; the merits of the scheme are not considered. More in our guide to planning application types.

• 7 SIDMOUTH AVENUE, ISLEWORTH, TW7 4DW

  PA/2023/0610 Submitted 23 Feb 2023 50 yards away

  Ground floor rear extension 4.00 metres deep, maximum height 3.54 metres, 3.00 metres high to the eaves

  Granted Prior approval Extension 5 docs

• 65 Sidmouth Avenue, Isleworth, TW7 4DR

  P/2024/3245 Submitted 27 Sep 2024 50 yards away

  Certificate of Lawfulness for the proposed change of use from Use Class C3(a) to Use Class C3(b).

  Granted Lawful development 8 docs

• 14 SIDMOUTH AVENUE, ISLEWORTH, TW7 4DW

  P/2021/2208 Submitted 3 Jun 2021 50 yards away

  Certificate of Lawfulness for proposed erection of a rear roof extension incorporating hip to gable conversion and two front roof windows; Alterations to the existing ground floor rear extension comprising of the removal of the existing opens and installation of one new window and French doors to the house

  Granted Lawful development Extension Loft or dormer +1 5 docs

• 16 Sidmouth Avenue, Isleworth, TW7 4DW

  PA/2026/1784 Submitted 16 Jun 2026 50 yards away

  Ground floor rear extension 5.00 metres deep, maximum height of 3.20 metres, 3.00 metres high to the eaves

  Granted Prior approval Extension 7 docs

• 18 Sidmouth Avenue, Isleworth, TW7 4DW

  P/2024/4102 Submitted 4 Dec 2024 50 yards away

  Erection of single storey rear extension following demolition of existing conservatory.

  Granted Householder Extension Demolition 20 docs
  Small domestic

• 12 Crawford Close, Isleworth, TW7 4DP

  P/2026/2069 Submitted 15 Jul 2026 100 yards away

  Non material amendment to allow the increase of the width of the single storey side extension from 0.8m to 1.35m of planning permission P/2024/1156 approved 18/06/2024 for the erection of single storey rear, single storey side and part first floor rear extension to the house

  Refused Amendments Extension 3 docs
  Small domestic

• P/2026/2813 Awaiting decision

  150 Wood Lane, Isleworth, TW7 5EQ

  (GSGS877009741) Certificate of lawfulness proposed for the erection of a single storey outbuilding to be used as a home gym / playroom / shed in the rear garden of the house

  Received 5 Oct, published by the council 9 Oct 2026 Lawful development
• P/2026/2334 Granted

  69 Central Avenue, Hounslow, TW3 2QW

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

  Received 12 Aug, published by the council 16 Aug 2026 Lawful development
• P/2026/2459 Granted

  2 Letchworth Avenue, Feltham, TW14 9RY

  Certificate of Lawfulness for the proposed hip to gable roof conversion, installation of two front roof windows, and erection of a rear roof extension to the existing house.

  Received 28 Aug, published by the council 5 Sep 2026 Lawful development
• P/2026/2787 Awaiting decision

  13 Denbigh Road, Hounslow, TW3 4DU

  Certificate of Lawfulness for the proposed erection of a detached outbuilding in the rear garden.

  Received 1 Oct, published by the council 9 Oct 2026 Lawful development
• P/2026/2790 Awaiting decision

  14 Old Farm Close, Hounslow, TW4 7AB

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

  Received 1 Oct, published by the council 6 Oct 2026 Lawful development