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City of London, London

Retrospective planning applications in the City of London

In the Square Mile the homes are flats, many of them listed, and a retrospective application starts with the building rather than the apartment. The City of London has 637 listed entries and almost no houses. We survey your flat, draw what is built and prepare the application. Fixed quote after a free constraints check.

Fixed quote after a free constraints check

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  • £2m PI insured
  • 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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    Pencil resting on a dimensioned technical drawing beside a scale rule

    The City's own guidance for as-built work

    The City Corporation publishes no rule made only for retrospective applications that we could find. For homes, the document that carries most weight is the Barbican Estate Listed Building Management Guidelines: Volume I Introduction and Volume II Residential (SPD), alongside the City of London Local Plan 2015, adopted in 2,015. Both are applied to an alteration already made as they would be to one proposed.

    An application that does not cite the estate guidelines at all looks careless to an officer who knows them well. We set out the relevant volume and section, name the building element concerned and describe the change in the guidelines' own terms.

    On the Barbican the guidelines set out which parts of the estate may be altered and how. Replacement windows, balcony infill and changes to the fronts of flats are the typical subjects. The Barbican is listed, so work there is judged against its special interest rather than against general design tests.

    Our job in this case is to find the relevant provision, show the as-built work against it and explain, with photographs and drawings, why the change falls within or can be tolerated by the guidance.

    Rows of brick terraced houses and gardens on a residential street

    Local figures for City of London

    Figures with their unit, period and source
    MeasureValuePeriodSource
    Households living in a house2 % of households living in a house or bungalow (detached, semi-detached or terraced)Census 2021nomisweb.co.uk
    Population15,631mid-2025nomisweb.co.uk
    Householder decisions1 decisions1 July 2025 - 30 June 2026assets.publishing.service.gov.uk
    Minor application decisions173 decisions1 July 2025 - 30 June 2026assets.publishing.service.gov.uk
    Minor applications granted97.1 %1 July 2025 - 30 June 2026assets.publishing.service.gov.uk
    Lawful development certificate applications (PS1)16 certificates2025 Q2 to 2026 Q1 (1 Apr 2025 to 31 Mar 2026)assets.publishing.service.gov.uk
    Listed building entries637 list entries (Historic England, within the LPA boundary)—planning.data.gov.uk
    Grade I listed entries86 list entries—planning.data.gov.uk
    Conservation areas28 named conservation areas published by the council—planning.data.gov.uk
    Householder: alterations/extensions to a single dwellinghouse, from 1 Apr 2026548 GBP—ribblevalley.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 City of London
    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

    Almost no houses, almost no householder cases

    Only 2 per cent of City households live in a house, and the resident population is 15,631 across 4,914 households. In its latest year the council decided just 1 householder application, so there is no local record of how such cases are handled.

    Residential alterations here are full applications for flats, and the council decided 173 minor applications in the same year, granting 97.1 per cent. That is a figure for small applications of every kind, mostly commercial, and it should not be read as a sign for or against a residential retrospective case.

    The council also counted 16 certificates of lawfulness in the government return, which shows that owners do use that route for proof of lawful use or works.

    Listed flats and consent that is not planning

    The City has 86 Grade I and 82 Grade II* entries among its 637 listed buildings, and 28 conservation areas cover a large part of its territory. Altering a listed building without listed building consent is an offence, separate from planning permission. We tell you at the first call if consent is needed and who should prepare it.

    Planning permission for work in a listed flat does not replace consent. If you have bought a flat where earlier owners altered it, we recommend an early check of the council's record before any money changes hands. We can draw the as-built condition for either application.

    Leases, freeholders and ownership

    About 36.5 per cent of households own their home, so leases matter. Where the flat is held on a long lease, alterations normally need the freeholder's permission as landlord regardless of planning. That is a second relationship to manage, and an application is smoother when the landlord position is already settled.

    Where a managing agent or residents' association also holds approval rights, we ask for their written position as well. Some of that paperwork is more than a formality, because a flat sold with an unresolved alteration is hard to mortgage.

    A conveyancer will want both sets of paperwork when you sell. If the lease permitted the change but planning permission was never sought, a retrospective application is the right fix. If the lease did not permit it, that has to be resolved first.

    Route, fee and what we draw

    Where the work is more than 10 years old, a lawful development certificate in the City of London can prove lawfulness instead. Otherwise the application is judged on its merits within 8 weeks, and a householder fee of £548 applies only where the property qualifies as a dwellinghouse.

    We provide the survey, as-built plans, a heritage-aware design statement and the submission, checked by a second MCIAT chartered architectural technologist. For policy support see planning consultant in the City of London, and the City of London hub for our other services in the Square Mile.

    Send us the address, your lease and the dates of the work. If the flat is on a listed estate, include the managing agent's name and any earlier consents, and we will confirm which approvals are needed and a fixed quote after a free check.

    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.
    Georgian brick terrace with sash windows, arched fanlight doorways, stone steps and iron railings in London
    The street around you
    Move across the plinth — the blocks rise around the pointer.

    Questions

    Do I need listed building consent as well?

    If your building is listed, yes. Planning permission and listed building consent are separate. We check the listing and tell you which applications the as-built work needs.

    Can I apply if I am a leaseholder?

    Yes, but your lease may require the landlord's approval. The application form asks you to notify the owner of the land, usually the freeholder.

    How long does the City take to decide?

    The standard period is 8 weeks. Heritage consultation can lengthen it, so we allow for that.

    Sources and dates

    City of London skyline glowing at dusk across the Thames under a dramatic orange sky

    Tell us about your property.

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