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Single-storey rear extensions in Hillingdon

Hillingdon approved 1,395 of the 1,564 planning applications for single-storey rear extensions it decided in the last five years (89%), and the typical decision took 55 days.

London Borough of Hillingdon · planning applications received Oct 2021 to Oct 2026 · updated 25 Oct 2026

Approved

1,395 of 1,564

89% of decided applications; 35 withdrawn, 74 undecided

Typical time to a decision

55 days

median, from 1,562 decisions with both dates published

Decided within 8 weeks

999 of 1,562

8 weeks is the usual statutory period; councils can agree extensions

See what was approved near your own address

The The Signal Report shows approvals and refusals for single-storey rear extensions within 250 m, 500 m and 1 km of your home, the council's reasons for refusing similar schemes, your property's planning history and the constraints on the plot. Free preview for any address.

See a sample report

Recent decisions

  1. Approved10 SHOWERS WAY HAYES

    Erection of a single storey rear extension.

    39431/APP/2026/2128 · decided 23 Oct 2026

  2. Approved42 LARCH CRESCENT HAYES UB4 9DP

    Erection of a single storey rear extension, following the demolition of existing outbuilding. (Amended Description)

    74555/APP/2026/901 · decided 22 Oct 2026

  3. Refused17 THE DRIVE ICKENHAM

    Erection of Front Porch, ground floor rear extension, part first floor side and rear extension, alteration of roof

    27617/APP/2026/2114 · decided 22 Oct 2026

  4. Approved102, Heathrow, UB3 5AL

    Erection of a single storey rear extension, following the removal of the exiting rear extension

    80224/APP/2026/2017 · decided 20 Oct 2026

  5. RefusedHayes

    Erection of a part single part two storey rear extension.

    8799/APP/2026/2034 · decided 7 Oct 2026

Why Hillingdon refuses single-storey rear extensions

The council's own words, quoted from recent decision notices.

  1. Hayes

    “1. By virtue of the cumulative scale and bulk and the first floor flat roofed design the proposed rear extension would result in a dominant, incongruous and visually obtrusive form of development which would cause significant harm to the character, appearance and visual amenities of the pair of semi-detached dwellings and the surrounding area, contrary to Policy BE1 of the Hillingdon Local Plan: Part One- Strategic Policies (2012), Policies DMHB 11 and DMHB 12 of the Hillingdon Local Plan: Part Two- Development Management Policies (2020), Policies D1, D3 and D4 of the London Plan and the Nati…”

  2. 23, West Drayton

    “1. The proposed first floor rear extension, by reason of its combined and excessive scale, design, bulk, width with the previously constructed rear extensions, would result in an incongruous form of development which would fail to appear subordinate to the host property, harming the original design and appearance of the dwelling and failing to preserve or enhance the character and appearance of the West Drayton Green Conservation Area and would result in a low level of harm that would not be outweighed by the public benefits. Therefore, the proposal fails to comply with Policies HE1 and BE1 o…”

  3. Hayes

    “1. he proposed development, by reason of its overall scale, width, positioning, cumulative bulk and massing of the proposed 2-storey side extension, when combined with the existing hip to gable roof extension and large rear dormer, would result in an incongruous, visually awkward and over- dominant form of development that would fail to appear subordinate to the original dwellinghouse. The proposed two storey side extension would fail to respect the architectural composition of the host dwelling and would unbalance the appearance of the semi-detached pair. By virtue of the site's prominent co…”

Other home extensions in Hillingdon

All planning applications in Hillingdon

How these figures are made

Planning applications London Borough of Hillingdon received Oct 2021 to Oct 2026, from the council's public planning register as collected by Planning Signal. An application counts as a single-storey rear extension when its own description says so (rules-based classification, tested against blind labelled samples). Duplicate records of one application are counted once. The approval figure counts approved and refused planning applications only: withdrawn and undecided ones, lawful development certificates and prior approvals are left out. Decision times use the received (or validated) date and the decision date the council published.

Past decisions describe what happened to other applications. They are not a prediction for yours: every application is decided on its own design and the council's current policies.