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Bromley, London

Rear extension drawings in Bromley

Rear extension drawings for a Bromley house start at £695 including VAT. The council's design guide sets no depth figure, so what you can build depends on the house and the street, and on whether the address meets 51 per cent green belt, 47 conservation areas or one of 108 Article 4 directions.

From £695 (VAT included)

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  • Fixed fees, VAT included

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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 rear extension drawings

    Nine 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.

    8. Building regulations

      Technical drawings are coordinated with the structural engineer's calculations, the drainage and the planning conditions.

    9. Approval and hand-over

      Building control approval, then a next-steps pack covering the commencement notice, party wall timing and CIL.

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

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    Finished white-rendered rear house extension with large glazed doors

    What Bromley's design guide asks of a rear extension

    The yardstick is the Urban Design Guide SPD. On extensions it asks for three things: the addition should look subservient in scale, it should respond to the character of the house and its street, and its roof should relate to the building it joins. None of the three comes with a measurement.

    With no number to design to, an officer judges the scheme against the house in front of them. How much of the original back wall stays visible? Does the new roof meet the old one cleanly? Do the new walls loom over the next garden? We draw each of those relationships on the sheets so the case officer does not have to infer them.

    The guide is read with the Bromley Local Plan, adopted in 2,019. In practice a simple, clearly secondary extension has an easier time than one stretched to the longest depth the national rules allow, and we tell you at the survey where your idea sits on that scale.

    Two-storey rear extension under construction on a semi-detached house

    Local figures for Bromley

    Figures with their unit, period and source
    MeasureValuePeriodSource
    Green Belt share of the council area51 % of council area covered by green-belt polygons—planning.data.gov.uk
    Conservation areas47 named conservation areas published by the council—planning.data.gov.uk
    Article 4 directions108 Article 4 directions published by the council—planning.data.gov.uk
    Listed building entries412 list entries (Historic England, within the LPA boundary)—planning.data.gov.uk
    Householder decisions1,609 decisions1 July 2025 - 30 June 2026assets.publishing.service.gov.uk
    Householder applications granted78.6 %1 July 2025 - 30 June 2026assets.publishing.service.gov.uk
    Householder applications decided in time89.1 % decided within 8 weeks or an agreed extended period1 July 2025 - 30 June 2026assets.publishing.service.gov.uk
    Larger home extension prior approvals granted3 decisions2025 Q2 to 2026 Q1 (1 Apr 2025 to 31 Mar 2026)assets.publishing.service.gov.uk
    Larger home extension prior approvals refused15 decisions2025 Q2 to 2026 Q1 (1 Apr 2025 to 31 Mar 2026)assets.publishing.service.gov.uk
    Householder appeals decided by the Planning Inspectorate502 householder appeals decideddecision dates 1 Jul 2021 to 30 Jun 2026assets.publishing.service.gov.uk
    Householder appeals allowed37.6 % of householder appeals alloweddecision dates 1 Jul 2021 to 30 Jun 2026assets.publishing.service.gov.uk
    Domestic gardens share of land (GLUD 2005)23.4 % of land that is domestic garden (GLUD 2005)2005data.london.gov.uk
    Class A, para A.1(g)6 m (attached) / 8 m (detached), single storey, height max 4 m; not on article 2(3) land or an SSSI—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 Bromley

    Householder applications by street in Bromley

    Streets in Bromley with the most householder applications, and the share approved
    StreetApplicationsApproved
    Petts Wood Road3981%
    Hayes Way3667%
    Crescent Drive3472%
    Village Way3281%
    Pickhurst Rise3187%
    Hayes Chase3083%
    Charterhouse Road2788%
    Farnaby Road2788%
    Kings Hall Road2591%
    St Paul's Wood Hill2588%
    Eden Park Avenue2477%
    Kent House Road2490%
    Broxbourne Road2391%
    Clock House Road2386%
    Elmstead Lane2381%
    Counts of householder applications by street; no individual applications are shown. Streets with fewer than five applications are left out.Source: GLA Planning London Datahub, householder applications, all years held. Contains public sector information licensed under the Open Government Licence v3.0. Contains OS data © Crown copyright and database right 2026.
    Single-storey rear extension: the permitted development limitsDepth beyond the original rear wall: 3 m (attached) / 4 m (detached) beyond the original rear wall, single storey. Maximum height: 4 m. Within the zone near the boundary: Eaves no higher than 3 m where within 2 m of the curtilage boundary. Larger extension under prior approval: 6 m (attached) / 8 m (detached), single storey, height max 4 m; not on article 2(3) land or an SSSIABCD

    Single-storey rear extension: the permitted development limits

    The house in section with a rear extension; the dashed lines mark the zone near the boundary.

    A · Depth beyond the original rear wall
    3 m (attached) / 4 m (detached) beyond the original rear wall, single storey
    B · Maximum height
    4 m
    C · Within the zone near the boundary
    Eaves no higher than 3 m where within 2 m of the curtilage boundary
    D · Larger extension under prior approval
    6 m (attached) / 8 m (detached), single storey, height max 4 m; not on article 2(3) land or an SSSI

    Prior approval, permitted development or planning in Bromley

    Without a local depth rule, many owners begin with the national routes. A single-storey extension can reach 3 m (attached) / 4 m (detached) beyond the original rear wall, single storey as permitted development, and a deeper one goes through prior approval at 6 m (attached) / 8 m (detached), single storey, height max 4 m; not on article 2(3) land or an SSSI. The wider picture is in our rear extension drawings guide.

    Bromley's record on the longer route is a warning. In the latest national statistics it granted 3 larger home extensions and refused 15. The numbers are small and from a single year, yet they point the same way each time: show the neighbours' windows and boundaries, and leave nothing for the officer to guess.

    A flat has no permitted development for extensions, and an Article 4 direction or a planning condition can remove the rights from a house. Prior approval is closed in a conservation area. Each of these turns the work into a householder application, and the address check tells us which applies.

    Green belt, Article 4 and heritage in Bromley

    More than half the borough is green belt, mapped at 51 per cent, and national policy resists additions that are disproportionate to the original building. The original footprint is therefore the first thing we establish on a house near the edge, because earlier additions count against you.

    Add 47 conservation areas and 108 Article 4 directions, and two similar houses can sit under different rules. Historic England lists 412 entries in the boundary. A listed house needs separate consent before the rear wall is touched, so say so on the first call if yours might be one.

    Decisions and appeals on Bromley householder cases

    Bromley decided 1,609 householder applications in its latest published year and granted 78.6 per cent, with 89.1 per cent decided on time. Of 502 householder appeals decided by the Planning Inspectorate, 37.6 per cent were allowed.

    These describe the past across every kind of home project. They set expectations for timing, and they remind owners that a refusal can be challenged. Houses are 68.6 per cent of households and domestic gardens cover 23.4 per cent of the land, so the garden is the space most rear extensions draw on, and the space officers weigh against the depth.

    The drawing set and the fee

    A Bromley set shows existing and proposed floor plans, sections and elevations, with the location and block plans. It starts at £695 with VAT included, fixed before you commit. Another chartered technologist checks every sheet, and we redraw free of charge until approval if officers ask for changes. The council's householder fee, £548, goes to Bromley directly.

    Other projects and nearby councils

    A wider plan may suit side return extension drawings in Bromley or the combined house extension drawings in Bromley. For the borough as a whole, see architectural drawings in Bromley. Near the boundary, compare the rules in Croydon and Greenwich.

    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.
    House extension under construction with scaffolding, new glazed doors and building materials
    Every side considered
    Flick across the turntable to spin it.

    Other services in Bromley

    Rear extension drawings nearby

    Questions

    How deep can a rear extension be in Bromley?

    The design guide sets no depth figure. Permitted development allows 3 m (attached) / 4 m (detached) beyond the original rear wall, single storey, subject to conditions, and anything beyond is judged on its merits.

    Does green belt stop a rear extension in Bromley?

    Not automatically, but about 51 per cent of the borough is green belt and extensions there must not be disproportionate to the original building.

    Do I need prior approval for a deeper extension in Bromley?

    For a single-storey extension beyond the ordinary limit, yes: the national figure is 6 m (attached) / 8 m (detached), single storey, height max 4 m; not on article 2(3) land or an SSSI, and neighbours are consulted before the council decides.

    How much do rear extension drawings cost in Bromley?

    From £695 including VAT, fixed up front. The council's fee is separate.

    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.

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