21 ADELPHI CRESCENT HAYES UB4 8LZ

1. 26 Nov 2025

   Received by Hillingdon

2. 7 Aug 2026

   Added to PlanIndex

3. Decision

   Awaiting decision

   Decision expected by 21 January 2026, 8 weeks from validation under the statutory target for most applications. Extensions of time are common and are agreed case by case.

   Hillingdon took a median of 58 days over the applications it decided in the last year.

This application is with Hillingdon 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.

This page mirrors an entry on the statutory planning register that Hillingdon is required to keep. The published feed for this record does not state which type of application it is, which is common for older entries and for some council systems; the register entry on the council portal will say, alongside the case officer and any consultation dates.

Every planning application follows the same broad path: submission, validation, publicity, then a decision by officers or committee. Our guide to planning application types explains the common types and what each can approve.

• 19 ADELPHI CRESCENT HAYES UB4 8LZ

  74902/APP/2019/3302 Submitted 9 Oct 2019 0m away

  Single storey rear extension and conversion of roof space to habitable use to include a rear dormer, 2 front rooflights and conversion of roof from hip to gable end (Application for a Certificate of Lawful Development for a Proposed Development)

  Granted Full applications Extension Loft or dormer 11 docs
  Small domestic

• 21 ADELPHI CRESCENT HAYES UB4 8LZ

  78333/APP/2026/240 Submitted 28 Jan 2026 0m away

  non-material amendment to planning permission ref. 78333/APP/2024/723, dated 05/06/2024 (Erection of a single storey detached building to the rear for use as a residential annexe) to add a Shower and WC

  Granted Full applications 7 docs
  Small domestic

• 18 ADELPHI CRESCENT HAYES UB4 8LZ

  72688/APP/2025/2960 Submitted 24 Nov 2025 0m away

  Conversion of a single dwelling house into 2no. self contained Flats.

  Refused Full applications New dwelling 21 docs
  Domestic

• 85 ADELPHI CRESCENT HAYES UB4 8NB

  79531/APP/2025/2248 Submitted 20 Aug 2025 101m away

  86% historically approved · decision due ~15 Oct

  Conversion of roof space to habitable use to include hip to gable extension, rear dormer, gable end window and x 2 front roof lights (Application for a Certificate of Lawful Development for a Proposed Development)

  Awaiting decision Extension Loft or dormer +1

• 17 DORSET AVENUE HAYES UB4 8NR

  79813/APP/2025/3031 Submitted 2 Dec 2025 107m away

  Conversion of roof space to habitable use to include a rear dormer, Hip to gable extension, 3x front roof lights, and erection of outbuilding to rear garden (Application for a Certificate of Lawful Development for a Proposed Development).

  Granted Full applications Extension Loft or dormer 5 docs

• 17 DORSET AVENUE HAYES UB4 8NR

  79813/APP/2025/3032 Submitted 2 Dec 2025 107m away

  Erection of front porch, and part single storey part double storey rear extension.

  Granted Full applications Extension 6 docs
  Small domestic