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Southwark, London

House extension drawings in Southwark

House extension drawings for a Southwark home start at £695 including VAT. Southwark's Householder SPD gives numbers to design against, and the borough holds 480 Article 4 directions, so the first check is whether your street has lost any of its permitted development rights.

From £695 (VAT included)

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    Finished white-rendered rear house extension with large glazed doors

    Southwark's own rules for house extensions

    The council's guidance is the Householder development SPD, which sits under the Southwark Plan 2022. For a rear extension that needs permission it asks for: 6 m depth; 4 m height; 2.4 m at boundary. Going deeper than the boundary depth is, in the council's words, likely to be refused, so depth is the number we pin down first.

    The same guidance limits how much of the plot you can build on. A rear extension must not take up more than 50% of the rear garden, and the council encourages single-storey schemes. For the neighbour's side, extensions are tested against the 45 degrees / 25 degrees rules, drawn from the centre of the nearest window.

    Side and wraparound schemes have separate lines. A side extension that needs permission should be single storey and set back from the street-facing facade by the council's figure (1.5 m set-back). An L-shaped or wraparound scheme is held to 6 m; 2.4 m; 50% across depth, eaves height and garden share, and must keep light to the outrigger window.

    Two-storey side extensions are not encouraged. The guidance wants them to avoid a terracing effect and to match the existing roof, and in a conservation area they fail if they close the gap between buildings.

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

    Local figures for Southwark

    Figures with their unit, period and source
    MeasureValuePeriodSource
    Rear extensions needing permission should stay below 6m deep on the boundary, at most 4m high, with the roof sloping down to no more than 2.4m at the boundary; over 6m on the boundary is likely to be refused.6 m depth; 4 m height; 2.4 m at boundary—southwark.gov.uk, Householder SPD 2025, p.73, section 3.5.2 and Figure 29
    Rear extensions must not take up more than 50% of the total rear garden and are encouraged to be single storey.50%—southwark.gov.uk, Householder SPD 2025, p.71 (section 3.5); p.73, section 3.5.2
    Side extensions needing permission should be single storey and set back 1.5m from the street-facing facade.1.5 m set-back—southwark.gov.uk, Householder SPD 2025, p.69, section 3.4.1
    L-shaped or wrap-around extensions should be no deeper than 6m on the boundary, stay below 2.4m at the eaves, keep light to the outrigger window, and use no more than 50% of the rear garden.6 m; 2.4 m; 50%—southwark.gov.uk, Householder SPD 2025, p.74, section 3.5.3
    Conservation areas53 named conservation areas published by the council—planning.data.gov.uk
    Article 4 directions480 Article 4 directions published by the council—planning.data.gov.uk
    Tree preservation zones724 tree preservation zone polygons published by the council—planning.data.gov.uk
    Listed building entries919 list entries (Historic England, within the LPA boundary)—planning.data.gov.uk
    Householder decisions558 decisions1 July 2025 - 30 June 2026assets.publishing.service.gov.uk
    Householder applications granted94.8 %1 July 2025 - 30 June 2026assets.publishing.service.gov.uk
    Householder applications decided in time95.3 % decided within 8 weeks or an agreed extended period1 July 2025 - 30 June 2026assets.publishing.service.gov.uk
    GPDO 2015 Sch 2 Pt 1 Class A, para A.1(f)(i)3 m (attached) / 4 m (detached) beyond the original rear wall, single storey—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 Southwark

    Householder applications by street in Southwark

    Streets in Southwark with the most householder applications, and the share approved
    StreetApplicationsApproved
    Ivydale Road6098%
    Upland Road5192%
    Friern Road4695%
    Underhill Road3293%
    Landells Road2996%
    Crystal Palace Road2587%
    Melbourne Grove2491%
    Dunstans Road2391%
    Burbage Road2291%
    Turney Road22100%
    Hollydale Road21100%
    Court Lane1994%
    Harlescott Road19100%
    Henslowe Road19100%
    Barry Road18100%
    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

    Terraces, converted houses and the garden you have

    Only 21.8 per cent of Southwark households live in a house or bungalow, so many houses here stand among flats and maisonettes. Gardens are small: domestic gardens cover about 17.6 per cent of the borough's land in the national land-use data. A garden-share limit bites hard on a short plot, which is why we survey the plot before we draw a depth.

    Where a house has already been converted into flats, an extension may not be a householder matter at all. We confirm the house is a single dwelling first, because permitted development for house extensions does not reach flats.

    Conservation areas, Article 4 directions and trees

    Southwark has 53 conservation areas, 480 Article 4 directions and 724 tree preservation zones, and Historic England records 919 list entries within the borough. Any of these can change the route for an extension, or the detail the council expects to see.

    A street with an Article 4 direction may need planning permission for work that is permitted development next door.

    Permitted development, prior approval or planning permission

    Nationally, a single-storey rear extension is permitted development within these limits: 3 m (attached) / 4 m (detached) beyond the original rear wall, single storey. A larger home extension notification can go further, and Southwark's recent record is small: the council granted 7 and refused 2 in the latest published year.

    Where the rights apply, a Lawful Development Certificate in Southwark confirms them in writing. Where they do not, or where the design needs more than the rights allow, the work goes through householder permission, drawn as in our planning drawings in Southwark.

    How Southwark has been deciding householder applications

    Southwark decided 558 householder applications in its latest published year. It granted 94.8 per cent and decided 95.3 per cent within eight weeks or an agreed extension. These are borough-wide figures for all householder work. They help us plan timing and say nothing about a particular house.

    Our drawings and fee for a Southwark extension

    A Southwark set shows the existing and proposed plans, all elevations, a section through the extension and the location and block plans, with the depth, height and set-back dimensioned against the SPD figures above. The fee starts at £695 with VAT included. A second chartered technologist checks each sheet, and we redraw free of charge if the council asks for changes before a decision.

    Once you have permission, our building regulations drawings in Southwark add the structure, insulation and fire detail.

    Other extension types and nearby councils

    For a single shape, see rear extension drawings in Southwark, wraparound extension drawings or side return extension drawings. The borough overview is architectural drawings in Southwark. Next door, compare house extension drawings in Lambeth and in Tower Hamlets.

    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 Southwark

    House extension drawings nearby

    Questions

    How deep can a rear extension be in Southwark?

    Southwark's Householder SPD says rear extensions needing permission should stay within 6 m depth; 4 m height; 2.4 m at boundary, and that going over the boundary depth is likely to be refused.

    How much of my garden can I build on in Southwark?

    The SPD does not allow a rear extension to take up more than 50% of the rear garden.

    Does Southwark restrict permitted development?

    In places. The council publishes 480 Article 4 directions and 53 conservation areas, and in these areas an extension may need an application. We check the address before we advise.

    How much do house extension drawings cost in Southwark?

    From £695 including VAT, fixed up front. Council fees are paid separately to the council.

    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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