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Hillingdon, London

Retrospective planning application in Hillingdon

Hillingdon publishes a long list of Article 4 directions and tree preservation orders, which is why work that seemed to need no permission sometimes does. A retrospective planning application regularises it. The council granted 90.2 per cent of 1,147 householder decisions. Fixed quote after a free constraints check.

Fixed quote after a free constraints check

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  • LABC Partnered
  • Fixed fees, VAT included

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We use it to check conservation areas and constraints.
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    Architectural model of a four-storey London stucco townhouse in its terrace, with a portico, area railings, sash windows, a cornice and chimney stacks
    The house as it stands: four storeys over a lower ground floor.Existing Proposed worksAn illustrative model, built for this page.

    How we work on retrospective planning applications

    Seven steps from first call to approval.

    The same model cut through the middle: every floor, the stair, the chimney breasts, the new mansard, rear extension and basement in section
    Section through the model: every floor on one datum.

    1. Enquiry and constraints check

      We check the property against conservation areas, listed status, Article 4 directions, tree preservation orders, flood zone and planning history. We choose the right route and send a fixed quote.

    2. Measured survey

      We survey the house on one datum: rooms, levels, boundaries, drains, trees and the neighbours' windows that the 45° and 25° tests depend on.

    3. Design options

      We model the house in Revit and show you options in 3D and plan, with the planning strategy and the precedents in your street.

    4. Design frozen

      You choose an option in writing. Nothing changes after this without your say.

    5. Independent check

      A second chartered technologist checks every sheet against the council's validation checklist and the policy. A senior review signs it off before anything is submitted.

    6. Submission

      We prepare the forms, certificates, fee and documents and submit through the Planning Portal.

    7. Officer liaison

      We answer the planning officer and make any amendments within five working days, at no charge until approval.

    Free redraws until approval. Every drawing set is checked independently, and the checker is never the person who drew it.

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    Rear view of brick terraced houses in London with slate roofs and chimney stacks along the shared roofline

    Why Hillingdon properties end up needing a retrospective application

    The borough publishes 150 Article 4 directions, mapped as 150 areas. Each one removes some permitted development rights, so a porch, outbuilding, hard standing or front-boundary wall that would be exempt elsewhere may have needed permission at your address.

    On top of that Hillingdon records 731 tree preservation orders. Building near a protected tree, or cutting its roots for a foundation, is the kind of problem that appears only when the neighbour or a buyer starts asking questions. We map both layers against your plot before we draw anything.

    The council applies the Hillingdon Local Plan Part 1: Strategic Policies, with Local Plan Part 2: Development Management Policies and Site Allocations and Designations (January 2020), adopted in 2,012, so older policies sit behind many decisions. The borough has not listed a householder design SPD in the data we hold, so we read the plan policies directly and cite the clause each drawing answers.

    Pencil resting on a dimensioned technical drawing beside a scale rule

    Local figures for Hillingdon

    Figures with their unit, period and source
    MeasureValuePeriodSource
    Article 4 directions150 Article 4 directions published by the council—planning.data.gov.uk
    Tree preservation orders731 tree preservation orders published by the council—planning.data.gov.uk
    Green Belt share of the council area42 % of council area covered by green-belt polygons—planning.data.gov.uk
    Listed building entries436 list entries (Historic England, within the LPA boundary)—planning.data.gov.uk
    Heritage at Risk entries45 Heritage at Risk Register entries within the LPA boundary (Historic England)—planning.data.gov.uk
    Householder decisions1,147 decisions1 July 2025 - 30 June 2026assets.publishing.service.gov.uk
    Householder applications granted90.2 %1 July 2025 - 30 June 2026assets.publishing.service.gov.uk
    Householder applications decided in time94.3 % decided within 8 weeks or an agreed extended period1 July 2025 - 30 June 2026assets.publishing.service.gov.uk
    Lawful development certificate applications (PS1)529 certificates2025 Q2 to 2026 Q1 (1 Apr 2025 to 31 Mar 2026)assets.publishing.service.gov.uk
    Householder: alterations/extensions to a single dwellinghouse, from 1 Apr 2026548 GBP—ribblevalley.gov.uk
    TCPA 1990 s171B(1)-(3) as substituted by LURA 2023 s115, in force 25 Apr 202410 years—legislation.gov.uk

    A blank value means the figure has not been published, not that there are none. Check your own address with the council.

    Councils bordering Hillingdon
    Which application your project needsLawful Development Certificate decision: 8 weeks. Prior approval decision: 42 days. Householder decision: 8 weeksYour projectWithin permitted development?Lawful Development CertificatePrior approvalHouseholder applicationYesLarger rear extensionNoABC

    Which application your project needs

    The usual route for a house; flats and listed buildings follow other rules.

    A · Lawful Development Certificate decision
    8 weeks
    B · Prior approval decision
    42 days
    C · Householder decision
    8 weeks

    Green Belt and heritage across the borough

    About 42 per cent of Hillingdon is Green Belt. Extensions to homes there are weighed against the openness of the Green Belt, and a finished building has to be measured against the original house.

    The heritage list is long: 436 entries, including 9 at Grade I and 29 at Grade II*, plus 5 scheduled monuments. Historic England also lists 45 entries in the borough on its Heritage at Risk Register. If your house lies near any of them, the application needs a heritage view, and we will say so in the quote.

    How the council has been deciding householder cases

    Hillingdon decided 1,147 householder applications in its latest published year, and granted 90.2 per cent. Of those, 94.3 per cent were decided inside 8 weeks or an agreed extension.

    Applicants also made 529 lawful development certificate applications, and larger home extension prior approvals were granted 29 times and refused 13 times. Those numbers describe an average across the borough. Your own neighbours and your own street still shape the result.

    If you believe the building was lawful when built, a lawful development certificate in Hillingdon may be the stronger first step.

    Fee, time limit and charges

    The householder fee is £548 and the council has 8 weeks for a non-major case. Time runs against enforcement action too: most building works are protected after 10 years.

    Hillingdon charges levy at £160.43/m² (Residential dwelling houses C3, borough-wide) for houses, with mayoral charging at £60 per square metre as a base rate. Appeals against a refusal must be made within 12 weeks for householder cases; see planning appeals in Hillingdon.

    Trees, hard standing and front gardens

    Many Hillingdon cases begin at the front rather than the back: a paved drive, a new vehicle crossover or a boundary wall built where an Article 4 direction removed the right to do so. These are cheaper to draw than an extension, but they still need a proper location plan, a dimensioned site plan and photographs of the street.

    Where a protected tree stands within reach of the work, we add a simple tree constraints plan and recommend an arboricultural opinion before the application goes in. The council treats tree damage as its own matter, so it is cleaner to answer it with evidence on day one than to leave the officer to raise it.

    Finally, ask your neighbours whether they have received anything from the council. Hillingdon sends notice letters to adjoining owners, and an early, friendly conversation about what you built often reduces objections more than any drawing can.

    Our drawings and where to read next

    The set includes a measured survey, as-built and proposed plans, elevations, sections, a tree constraint sketch where it matters and the usual location and block plans. Our planning drawings in Hillingdon are checked by a second chartered technologist before issue.

    The price is fixed after your free check. For more on the area read architectural drawings in Hillingdon or the retrospective planning overview. We also cover Hounslow and Harrow.

    What you receive

    Planning drawing sheet for a rear extension with plans, elevations and sections
    Sample drawing. Planning drawings for a rear extension: plans, elevations and sections on one sheet set.
    Rows of brick terraced houses and gardens on a residential street
    The street around you
    Move across the plinth — the blocks rise around the pointer.

    Other services in Hillingdon

    Retrospective planning applications nearby

    Questions

    Does an Article 4 direction mean my extension needed permission?

    It may. Hillingdon publishes 150 directions, and each removes certain rights in its area, so we check yours first.

    Do tree preservation orders affect a retrospective application?

    They can. Hillingdon holds 731 orders, and damage or loss of a protected tree is a separate matter that we raise early.

    Is the intentional nature of the work a problem?

    It can be. Policy says: Evidence that unauthorised development was intentional should be given substantial weight. We help you give an accurate account.

    What does the council fee cover?

    The householder application fee is £548, paid to Hillingdon. Our own fee is separate and fixed.

    Sources and dates

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    Tell us about your property.

    We check the constraints, then send a fixed fee. Messages before 3pm get a reply the same working day.

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