Two Victorian terraced houses on a London street, one painted white and one in yellow stock brick, with bay windows
Floor plan drawings, pencil sketches of a house, a scale rule and a protractor spread across a desk
Photo: Tima Miroshnichenko / Pexels

Lawful development certificate · London Borough of Southwark

Lawful development certificate in Southwark, from £695 fixed

Southwark's own checklist for a lawful development certificate asks for more than the national minimum: a curtilage plan with areas in square metres, roof volume calculations, the distance from eaves to dormer and the projection of rooflights. We draw all of it, so the council can confirm the work is permitted development.

Lawfulness certificatefrom £545 drawings + £150 survey (£695 total)
Council fee£274
Get your fixed feeFFP-01 · Rev A
Our fixed fee£795
Council fee, paid to your council£548
Our fee + council fee£1,343
CoverageAll 33 boroughs

Householder application fee, paid to your council at submission.

Plus the Planning Portal's own charge if the application goes through the Portal: up to £149 including VAT, depending on the application type, and some types have none (source).

Get this fee in writing

or email hello@fixedfeeplans.co.uk

No obligation. Nothing is sent until you ask; your enquiry comes to us and nowhere else.

Starts at£150
Boroughs33/33
Stages5

Photo: Huy Phan / Pexels

Fixed fee, in writing

Tell us about your project

Send the postcode and what you want to build, and add photos or old plans if you have them. We reply with the fee in writing and the payment stages set out in full.

Ask for your fixed fee in writing

Name and email are required. Everything else helps us price it, but is optional.

Your enquiry goes to us and nowhere else. It is never syndicated or sold. See our privacy notice.

The tiled roofs and upper floors of brick semi-detached houses in Canterbury, England, with trees behind
Semi-detached houses in Canterbury, England. Photo: angie duong / Pexels.

What Southwark Council asks of a lawful development certificate

From the council's Planning checklists: lawful development certificate application (adopted current checklist, read 25 October 2026).

  • Southwark asks for Community Infrastructure Levy information with every application type, lawful development certificates included: the CIL additional information requirement form, with colour-coded plans and further CIL forms where relevant. (source, checked 25 October 2026)
  • For an extension, at least one plan must show the entire curtilage of the property, giving the area of the curtilage and the area of the extension or outbuilding in square metres, and any side-facing windows must be shown as opening or fixed and as obscure glazed or not. (source, checked 25 October 2026)
  • For roof alterations the council wants full calculations of the existing and proposed cubic content of the roof space, the projection of any rooflight from the roof slope, and the distance between the eaves of the original roof and the bottom of any dormer. (source, checked 25 October 2026)
  • Where ceiling or roof heights change, including basements, sunken patios and decking, existing and proposed sections are needed with written dimensions, labelling any living space with a ceiling height of less than 2.3 metres. (source, checked 25 October 2026)
  • For a listed building, the certificate application needs a schedule of works, the published listing description and a statement explaining why the works would not affect its special interest and so need no listed building consent. (source, checked 25 October 2026)

What Southwark lawful development certificate drawings have to show

Southwark's checklist turns the permitted development tests into drawing requirements. For a rear extension, a curtilage plan gives the garden area and the footprint of the extension in square metres, so the officer can see the 50 per cent limit is met. For a loft, a calculation sheet sets out the original and proposed roof volume in cubic metres, and the side elevation dimensions how far the dormer sits above the eaves.

Every proposed drawing carries a unique reference number, a scale bar and written dimensions, as the checklist asks, and the site plan is at 1:100 or 1:50 with a north arrow and the neighbouring buildings labelled. We complete the CIL additional information form with the application, because Southwark asks for it on certificates as well as planning applications.

PS2 · at a glance

Southwark: 558 householder decisions

Southwark
Approvals, prior approvals included94.8%

529 of 558 granted. London: 85.8%.

Decided within 8 weeks97.5%

424 of 435 applications, prior approvals excluded.

Source: MHCLG PS2, 1 July 2025 to 30 June 2026. Dark tick: London.
Floor plan drawings, pencil sketches of a house, a scale rule and a protractor spread across a desk
Sketches and floor plans: the existing and proposed drawings start as a measured layout like these. Photo: Tima Miroshnichenko / Pexels.

What it costs in Southwark

  • Certificate of lawfulness: from £545 drawings + £150 survey (£695 total), plus £274 to Southwark Council.
  • Half the equivalent planning fee for a proposed use certificate.

Lawful development certificate across London · Southwark planning rules · every price

Answers

Southwark lawful development certificate questions

What drawings does Southwark need for a lawful development certificate?
A site plan at 1:100 or 1:50, existing and proposed floor plans and elevations, and sections where heights change. For extensions, a plan of the whole curtilage with its area and the extension area in square metres. For a loft, roof volume calculations and the distance between the eaves and the bottom of the dormer.
Does Southwark need a CIL form with a certificate of lawfulness?
Yes. Southwark's checklist says CIL information must be submitted for all application types, including lawful development certificates. That means the CIL additional information requirement form, plus colour-coded plans and further CIL forms where they apply. We complete the form with the application so it is not held up at validation.
Can I get a lawful development certificate for a listed building in Southwark?
Yes, for works that do not need planning permission. Southwark asks for a detailed schedule of the works, the listing description and a statement explaining why they would not affect the building's special interest, and so would not need listed building consent. External extensions to listed houses usually need consent instead.

Start with £150

Your fixed fee is already on this page.

Tell us the postcode and what you want to build. We confirm the fee in writing and book the survey.

Get my fixed fee020 7131 9703
01
Measured surveyWithin five working days
£150
02
Existing drawingsThe building as it stands
£175
03
Proposed drawingsYour scheme, revised until right
£225
04
Planning application packForms, statements, OS plans
£125
05
Submission and agent servicePortal submission, queries handled
£120
Total, planning application£795
Get my fixed fee