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Slate-clad roof extension on a yellow-brick London terraced house
Photograph: Daniel Sikpi

01Southwark, London

Mansard roof drawings for houses in Southwark

Southwark is specific about mansards. Its householder guidance says they always need permission, that they sit behind the front and rear parapets and that the pitch is capped at 70 degrees. Our chartered architectural technologists (MCIAT) draw to that envelope from £845 including VAT.

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    Write to us before 3pm and we reply the same working day. Redraws are free until approval.

    02The brief

    What the householder SPD says about mansards

    The Householder development SPD treats a mansard as a planning matter every time. It must sit behind the front and rear parapets at no more than 70 degrees. It also rules out two settings by name: a mansard over an outrigger and one on an unbroken run of butterfly roofs, which are paired slopes falling to a central valley behind the parapet.

    With the permitted route closed, the drawings are the whole case. We survey the parapet heights, the outriggers and the neighbouring roofs so the pitch is measured against the rule on a common datum and not estimated from the street.

    Rear view of brick terraced houses in London with slate roofs and chimney stacks along the shared roofline
    Brick cottage with a tiled roof, chimneys and a front dormer window
    Photograph: Tanya Barrow

    03The record

    Local figures for Southwark

    Figures with their unit, period and source
    MeasureValuePeriodSource
    Mansards always need permission, must sit behind the front and rear parapets at a maximum 70 degrees, and are not permitted over an outrigger or where there is an unbroken run of butterfly roofs.70 degreesNo periodsouthwark.gov.uk, Householder SPD 2025, pp.77-78, section 3.6.4
    Supplementary planning documentHouseholder development SPD2025southwark.gov.uk
    Class B, condition B.2(b)(i)(aa)Class B requires the original eaves to be maintained or reinstated, which a parapet-fronted mansard normally removesNo periodlegislation.gov.uk
    Class AA, para AA.1(b)Class AA is not available on article 2(3) landNo periodlegislation.gov.uk
    Party Wall etc. Act 1996 s3(2)(a)Party structure notice at least 2 months before workNo periodlegislation.gov.uk
    Householder: alterations/extensions to a single dwellinghouse, from 1 Apr 2026548 GBPNo periodribblevalley.gov.uk
    Conservation areas53 named conservation areas published by the councilNo periodplanning.data.gov.uk
    Article 4 directions480 Article 4 directions published by the councilNo periodplanning.data.gov.uk
    Householder applications granted94.8 %1 July 2025 - 30 June 2026assets.publishing.service.gov.uk

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

    Southwark7 neighbouring councils
    Councils bordering Southwark

    04The streets

    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.

    GLA Planning London Datahub, householder applications

    05The drawing

    A mansard roof in sectionA, Southwark: lower slope: 70 degrees. B, Permitted development and the eaves: Class B requires the original eaves to be maintained or reinstated, which a parapet-fronted mansard normally removes. C, Additional storeys under permitted development: Class AA additional storeys exclude houses built before 1 Jul 1948 or after 28 Oct 2018. D, Fire protection to the stair: New storey above 4.5 m by loft conversion: protect the full escape route with fire-resisting doors (min E 20) and partitions (min REI 30)ABCD

    A mansard roof in section

    A London terrace with a mansard behind the parapet. The lettered marks show the limits the legend gives.

    A Southwark: lower slope
    70 degrees
    B Permitted development and the eaves
    Class B requires the original eaves to be maintained or reinstated, which a parapet-fronted mansard normally removes
    C Additional storeys under permitted development
    Class AA additional storeys exclude houses built before 1 Jul 1948 or after 28 Oct 2018
    D Fire protection to the stair
    New storey above 4.5 m by loft conversion: protect the full escape route with fire-resisting doors (min E 20) and partitions (min REI 30)
    The mansard in three dimensions3D
    Scroll the page: the model turns with it.

    06The detail

    The designations around a Southwark roof

    Southwark has 53 conservation areas, and planning data lists 480 Article 4 direction records. Class AA is not available on article 2(3) land, and that includes conservation areas, so an upward extension there needs a householder application.

    Directions are made area by area. In Dulwich, Southwark publishes Article 4 directions for the Sunray Estate Conservation Area. The Dulwich neighbourhood guide sets out the other designations there.

    Listed roofs and past householder decisions

    Historic England records 919 list entries in the borough, and a mansard on a listed house needs consent as well as permission. Start with listed building consent drawings in Southwark.

    Across 558 householder decisions the council granted 94.8%, and 95.3% were decided on time. Those figures cover every kind of household work, not only roofs, and say nothing about a particular street.

    What the set contains and what it costs

    Existing and proposed roof plans, a section through the parapet and the neighbouring roofs, and elevations of the street frontage. The Party Wall etc. Act 1996 sets the timing for a party structure notice: Party structure notice at least 2 months before work.

    Our fixed fee starts at £845 including VAT. The council's householder fee of £548 is separate, and redraws are free until approval.

    Planning sheet for a single-storey rear extension: proposed ground floor plan and rear elevation, with the Property Architecture title block
    Sample drawing. Proposed plan and rear elevation from a planning application set, sheet 03 at 1:50.

    07The papers

    What the drawings rest on

    Converted loft bedroom with roof windows and a Juliet balconyLoft conversions
    Photograph: Imad Clicks
    Loft floor plan marked up in an independent review, with three critical issues clouded and explained
    Sample drawing. A loft plan with the reviewer’s mark-up: stair pitch, dormer cheeks and roof ventilation.

    08Correspondence

    Questions

    Can I add a mansard to a Southwark house without planning permission?

    No. The householder SPD states that a mansard always needs permission. Nationally, Class B requires the original eaves to be maintained or reinstated, which a parapet-fronted mansard normally removes, and Class AA is not available on article 2(3) land.

    What pitch can a Southwark mansard have?

    The SPD sets a maximum of 70 degrees, with the roof behind the front and rear parapets. We fix the pitch at the first design option so the headroom is known before the design is frozen.

    Does a butterfly roof rule out a mansard?

    The SPD rules out a mansard on an unbroken run of butterfly roofs. A broken run, or a roof of another form, is a different case, so we check the neighbours' roofs from the survey and tell you which applies.

    Upper floors of a large yellow-brick Victorian house in London with chimney pots

    94.8%

    Householder applications granted, Southwark, 1 July 2025 - 30 June 2026. Source: assets.publishing.service.gov.uk

    Photograph: Lorenc Memaga

    09Further reading

    Other services in Southwark

    Mansard roof drawings nearby

    10Sources

    Sources and dates

    Licences

    Kensington street lined with brick townhouses and lit streetlamps beneath an orange dusk sky

    Send us the address of your house.

    We look up the conservation area, listing and Article 4 position, then reply with a fixed fee. A message before 3pm is answered the same working day.

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    Mansard roof drawings in Southwark: parapet and pitch rules