Free planning check
Free Lambeth planning permission check
Check in 23 seconds whether your Lambeth project needs planning permission, and what the council has approved near you. Phase 1 planning drawings: standard rear or side extensions from £995 and loft conversions from £1,495, paid only when the council approves. Council and Portal fees are paid separately at submission.
About the planning data
Checked against 20.6 million UK planning applications on file across 420 planning authorities. Approval rates from 2,343,419 decisions we classified across 181 councils in England.
Lambeth approval rates by project type
Historical approval rates in our archive, grouped by project type. These describe recorded decisions, not the chance of approval for your proposal. Checked against 20.6 million UK planning applications on file across 420 planning authorities. Approval rates from 2,343,419 decisions we classified across 181 councils in England.
| Project type | Approval rate | Decided |
|---|---|---|
| Single-storey rear extension | 82% | 3,310 |
| Two-storey rear extension | 77% | 359 |
| Wraparound extension | 84% | 695 |
| Side extension | 85% | 677 |
| Loft conversion and dormer | 76% | 1,116 |
| Rooflight | 84% | 2,205 |
| Outbuilding and garden room | 77% | 190 |
| Porch | 90% | 77 |
| Garage conversion | 87% | 63 |
| Basement | 86% | 2,031 |
| Window and door | 83% | 2,107 |
A rate is only shown where at least 8 applications of that type were decided; smaller samples are shown as unknown. Withdrawn and undecided records are excluded. These figures cover all recorded years, including records without a year. Full Lambeth approval rates.
Application guidance in Lambeth
Lambeth publishes a list of common validation problems, including missing CIL information and incomplete application forms. Its conservation profiles include designation reports, appraisals and maps, and explain how to check a property's constraints in the planning database. Read those records before finalising your submission.
- Lambeth Article 4 directions
- Lambeth conservation-area profiles and maps
- Lambeth common validation problems and local list
- Lambeth application validation process
Sources reviewed . Check the source maps, wording and effective dates against your property and proposed work.
Use the design guide part that matches your project
Lambeth's Design Guide SPD was adopted on 8 August 2023. Part 4 covers alterations, extensions and retrofit; Part 5 covers basements. Read the relevant part with the applicable Local Plan policies and site evidence. A roof design accepted at appeal elsewhere does not determine the answer for a heritage property. Read the council guidance.
What reviewed local decisions show
These examples use official planning records. Each identifies the decision date and links to the evidence reviewed. They are not Planning Approvals projects or a prediction for another property.
175 Lyham Road: a mansard allowed on its specific design
25/00454/FUL · APP/N5660/D/25/3364909 · Appeal allowed with conditions, 3 July 2025
The inspector granted permission for a mansard after the council's refusal. The property was not a heritage asset or in a conservation area. The decision considered the retained parapet, setbacks, roof proportions and varied street scene, and found the design acceptable in those circumstances.
What to check: Explain the roof form and its relationship to the building and street. This was planning permission granted on appeal, not confirmation that a mansard qualifies as permitted development.
Read the appeal decision (PDF)
Related guidance: Loft conversions and PD
30 Ferndene Road: structural drawings did not resolve the evidence gap
25/01406/FUL · APP/N5660/W/25/3373636 · Appeal dismissed, 20 January 2026
The inspector found the basement evidence insufficient on ground and surface water, drainage and land stability, despite additional structural drawings. Other concerns, including the design and living conditions, were not found harmful enough to justify refusal, but the unresolved basement impacts still led to dismissal.
What to check: Address the specific gaps raised in the assessment. Structural detail alone may not demonstrate groundwater and drainage impacts; this mixed rear-extension and basement scheme needed evidence for both.
Read the appeal decision (PDF)
Related guidance: Basement planning permission · Rear extensions
Check the planning register for the issued notice, exact conditions and any later appeal or revised application. A committee resolution is not a substitute for those documents.
Application records to compare
Selected archive records, not a representative sample or a prediction for your address. The descriptions below are archive excerpts and may be shortened; read the original decision and plans before relying on them.
- 23/01235/FUL · Recorded approved (2025)
Conversion of existing property into 3 self-contained flats involving the erection of a single storey ground floor rear and side infill extension (with court...
Search the council register for 23/01235/FUL - 24/01849/FUL · Recorded approved (2025)
Erection of a single storey ground floor rear extension.
Search the council register for 24/01849/FUL
Compare the property type, works and application route. A scheme involving flats or several alterations is not directly comparable to a simple house extension. Read the archive's coverage and limitations.
Lambeth planning resources
Check the authority's current records for the property's planning history, application requirements and local restrictions.
Prepare for your planning application
Questions about planning in Lambeth
Do I need planning permission for my project in Lambeth?
Some house extensions, loft conversions and outbuildings can use permitted development rights in Lambeth, but size alone does not establish eligibility. Check the property type, previous extensions, planning conditions and the rules for the proposed work. Householder rights do not apply to flats. Conservation areas and Article 4 directions restrict particular rights; they do not automatically require an application for every change. Listed building consent is a separate requirement for works affecting a listed building's special interest.
What is the planning approval rate in Lambeth?
It depends on the project type. 82% of 3,310 decided single-storey rear extension applications in Lambeth were approved. 76% of 1,116 decided loft conversion and dormer applications in Lambeth were approved. Checked against 20.6 million UK planning applications on file across 420 planning authorities. Approval rates from 2,343,419 decisions we classified across 181 councils in England. Every project type is on the Lambeth approval rates page.
Read the official guidance on when permission is required, listed buildings and conservation areas and planning decision periods.
Approval rates are computed from 2,343,419 decided applications across 181 councils, published by each council. The free check is guidance from the public record, not a council decision.