Lawful development certificate drawings for Southwark, £539
Southwark tells applicants for roof works to include full calculations of roof-space cubic content, rooflight projection and the dormer’s distance from the eaves. We draw those into the pack from our own survey.
- £389 drawings + £150 survey (£539 total)
- Roof volume calculation
- Evidence list for old works
What does a lawful development certificate pack cost in Southwark?
We charge £539: £389 for the drawings, forms and submission and £150 for the survey, with no VAT to add. Southwark Council’s certificate fee is paid to the council.
What the Southwark price covers
- A survey, with the curtilage area measured in square metres
- Site plan at 1:100 or 1:50, floor plans and elevations with written dimensions
- For roof works, the cubic content of the existing and proposed roof space
- Rooflight projection and dormer-to-eaves distances marked on the drawings
- The CIL additional questions form and submission, or an evidence list for existing works
What Southwark’s certificate checklist asks to see
Southwark says a certificate confirms that proposed works are permitted development, or that an old development is immune from enforcement, or that something is not development at all. For works to a home it asks for at least one plan including the whole curtilage with the curtilage area and the extension or outbuilding area in square metres, and for side-facing windows to be marked as opening or obscure glazed (Southwark checklist).
For roof alterations it wants full calculations of the existing and proposed cubic content of the roof space, the projection of any rooflight marked on the drawings, and the distance from the original eaves to the bottom of any dormer. A CIL additional questions form goes in with every application type.
Existing works: the evidence rule
When the certificate is for existing works, Southwark says evidence must be clear and convincing and at least two different kinds should be submitted. Its examples include a building control final inspection certificate, rent or account documents, Council Tax letters addressed to the unit, dated photographs, Google Street View screenshots and invoices from construction work.
Statements from owners that carry important evidence should be sworn in the proper form and be original documents. For example, an owner proving a dormer built years ago would combine dated Street View captures, the builder’s invoice and a sworn statement.
Constraints, validation and timing
The Sunray Estate conservation area on Denmark Hill carries its own Article 4 direction (Sunray Estate), and any conservation area removes permitted development rights that a certificate would otherwise confirm. For example, a certificate for a rear dormer on a Sunray Estate house would not be granted. At validation, Southwark checks the pack against the checklist above.
Southwark decided 424 of 435 householder applications inside 8 weeks in the year to June 2026. A certificate is a separate application, so we cannot promise its date.
Southwark certificate applications in numbers
- 2 kinds
- Southwark asks for at least two different types of evidence when the certificate covers existing works. Southwark: lawful development certificate checklist
- 1:100 or 1:50
- Scales Southwark asks for on site plans, floor plans and elevations in a certificate application. Southwark: lawful development certificate checklist
- Cubic content
- Southwark asks for full calculations of the existing and proposed cubic content of the roof space for roof alterations. Southwark: lawful development certificate checklist
- All applications
- Southwark asks for CIL information with every application type, certificates included. Southwark: lawful development certificate checklist
- Sunray Estate
- Southwark’s Article 4 direction for the Sunray Estate conservation area on Denmark Hill. Southwark: Sunray Estate Article 4 direction
- 424 of 435
- Southwark Council householder applications decided within 8 weeks in the year to June 2026, out of all it decided (prior approvals not counted). MHCLG live table PS2, planning application statistics by district, July 2025 to June 2026 (GOV.UK)
- £72.73 per m²
- The Mayor of London’s CIL in Southwark (band 2) for permissions granted in 2026, owed only when a scheme is liable for CIL in the first place. Mayoral CIL: annual rate summary for 2026, Table 1 (Greater London Authority)
Southwark certificate questions
Does Southwark need a roof volume calculation?
For roof alterations, yes: full calculations of the existing and proposed cubic content of the roof space, plus the rooflight and dormer measurements.
What proves an old extension is lawful?
Southwark wants clear evidence, at least two different types, such as building control certificates, invoices, dated photographs and Council Tax records.
Does a certificate need a CIL form?
Yes. Southwark asks for CIL information with every application type.
Is a certificate the same as planning permission?
No. It confirms the works are lawful, normally permitted development, so permission is not needed.
Other services people book with this one
- Rear extension drawings£439 drawings + £150 survey (£589 total)
- Loft conversion drawings£439 drawings + £150 survey (£589 total)
- Prior approval for a larger home extension£349 drawings + £150 survey (£499 total)
- Householder planning drawings£479 drawings + £150 survey (£629 total)
- Building regulations drawings£479 drawings + £150 survey (£629 total)
Price your Southwark certificate
Send the address and what you want built or proved. We say whether a certificate fits and quote a fixed fee.