Which Lambeth postcodes does this basement extension service cover?
Every Lambeth postcode district we draw in, the stock that dominates
it and the authority that validates a basement extension there. Lambeth fees below are the
statutory England rates for 2026, not basement extension estimates.
| Postcode | Area | Dominant stock | What it means for a basement extension |
|---|
| SW9 | Brixton / Stockwell | Victorian terraces, post-war estates | SW9 covers Brixton / Stockwell only; Lambeth Council handles the basement extension. |
| SW16 | Streatham / Norbury | Edwardian terraces, post-war flats | SW16 straddles a boundary: Streatham / Norbury addresses fall to Lambeth Council or Wandsworth Council or Merton Council or Croydon Council, so confirm which authority validates the basement extension before submitting SW16 drawings. |
| SE1 | Bermondsey / Borough / Waterloo | Georgian terraces, post-war flats, new-build | A basement extension in Bermondsey / Borough / Waterloo may land with Southwark Council or Lambeth Council — SE1 crosses the boundary, and the SE1 policies map decides it street by street. |
| SE5 | Camberwell | Georgian villas, Victorian terraces | Camberwell is split at SE5. Either Southwark Council or Lambeth Council can determine a basement extension here, so the SE5 address is checked against both policies maps first. |
| SE19 | Upper Norwood / Crystal Palace | Victorian villas, Edwardian terraces | A basement extension in Upper Norwood / Crystal Palace may land with Croydon Council or Lambeth Council — SE19 crosses the boundary, and the SE19 policies map decides it street by street. |
| SE21 | Dulwich Village | Georgian villas, Edwardian villas (Dulwich Estate) | Dulwich Village is split at SE21. Either Southwark Council or Lambeth Council can determine a basement extension here, so the SE21 address is checked against both policies maps first. |
| SW12 | Balham | Victorian and Edwardian terraces | Balham is split at SW12. Either Wandsworth Council or Lambeth Council can determine a basement extension here, so the SW12 address is checked against both policies maps first. |
| SE11 | Kennington / Vauxhall | Georgian terraces, post-war estates | Kennington / Vauxhall sits wholly inside SE11, so Lambeth Council validates every basement extension submitted from an SE11 address. |
What changes about a basement extension in each part of Lambeth?
Roof pitch, wall build-up and plot depth change every few Lambeth
streets, and each one changes what a basement extension can achieve at that address.
- Streatham (SW16) — basement extension work in Streatham means edwardian terraces, post-war flats. Streatham is Edwardian terraces, post-war flats. Edwardian houses rarely have a usable cellar throughout SW16. Lambeth Council decides the Streatham application, and Streatham High Road anchors the Streatham location plan.
- Stockwell (SW9) — a basement extension in Stockwell starts from victorian terraces, post-war estates, and Stockwell reads as Victorian terraces, post-war estates. Victorian cellars here convert without planning permission when the footprint and external appearance are unchanged in SW9. Lambeth Council assesses Stockwell basement extensions against its own Stockwell character guidance, and the location plan we draw for Stockwell references Stockwell station.
- Vauxhall (SE11, SW8) — Regency fragments, riverside new-build defines Vauxhall, where regency terraces, modern apartments, post-war flats set what a basement extension can do. Post-war slab foundations make basements here expensive and rarely viable across SE11. Any Vauxhall basement extension is validated by Lambeth Council, with Vauxhall Bridge the usual Vauxhall reference point on the site plan.
- West Norwood (SE27) — basement extension work in West Norwood means victorian terraces, edwardian villas. West Norwood is Victorian terraces, Edwardian villas. Victorian cellars here convert without planning permission when the footprint and external appearance are unchanged throughout SE27. Lambeth Council decides the West Norwood application, and West Norwood Cemetery anchors the West Norwood location plan.
- Tulse Hill (SE27, SW2) — a basement extension in Tulse Hill starts from victorian villas, edwardian terraces, and Tulse Hill reads as Victorian villas, Edwardian terraces. Victorian cellars here convert without planning permission when the footprint and external appearance are unchanged in SE27. Lambeth Council assesses Tulse Hill basement extensions against its own Tulse Hill character guidance, and the location plan we draw for Tulse Hill references Tulse Hill station.
- Waterloo (SE1) — a basement extension in Waterloo starts from georgian terraces, post-war flats, new-build, and Waterloo reads as Georgian fragments, post-war estates, regen. Georgian houses here already have a vault and a lower-ground floor in SE1. Lambeth Council assesses Waterloo basement extensions against its own Waterloo character guidance, and the location plan we draw for Waterloo references Southbank Centre.
- Clapham (SW4) — basement extension work in Clapham means victorian terraces, edwardian villas. Clapham is Victorian terraces around the common. Victorian cellars here convert without planning permission when the footprint and external appearance are unchanged throughout SW4. Lambeth Council decides the Clapham application, and Clapham Common anchors the Clapham location plan.
How do conservation areas and Article 4 affect a basement extension in Lambeth?
Conservation areas covering Lambeth: Lambeth Council runs 64, and Kennington, Brockwell Park, Streatham Hill are the ones Lambeth owners meet most. A basement extension inside a Lambeth conservation area loses permitted development, so the Lambeth submission is a householder application at £548 decided in 8 weeks — not a £249 prior approval decided in 6 weeks. In Streatham Hill a basement extension is judged on the street elevation first.
Lambeth and Article 4: Borough-wide Article 4 for HMO conversions; plus office-to-residential restrictions. A basement extension planned at a SE11 address is checked against that direction first; Lambeth Council publishes the Lambeth extent, and the SE11 line rarely follows the Lambeth boundary you would expect.
Lambeth housing stock: Victorian terraces in Clapham, Brixton, Herne Hill; Edwardian villas; 1930s and post-war estates in parts of Streatham; Georgian in Kennington. Mix of dense Victorian residential and post-war estate; strong conservation area coverage; generally design-led planning decisions. Read that before choosing a basement extension route in Lambeth — construction, not postcode, sets what is achievable.
Who decides a basement extension on the edge of Lambeth?
- Westminster — cross the Lambeth boundary and Westminster City Council takes the basement extension instead, applying 56 conservation areas of its own around SW1. We re-price basement extensions at the Lambeth edge because Westminster policy and Lambeth policy rarely align on basement extension depth.
- Southwark — cross the Lambeth boundary and Southwark Council takes the basement extension instead, applying 43 conservation areas of its own around SE1. We re-price basement extensions at the Lambeth edge because Southwark policy and Lambeth policy rarely align on basement extension depth.
- Wandsworth — cross the Lambeth boundary and Wandsworth Council takes the basement extension instead, applying 45 conservation areas of its own around SW8. We re-price basement extensions at the Lambeth edge because Wandsworth policy and Lambeth policy rarely align on basement extension depth.
- Croydon — adjoining Lambeth, with 24 conservation areas centred on CR0. A basement extension on the far side of the Lambeth line is determined by Croydon Council, so the Lambeth quote for basement extensions is checked against Croydon guidance before it is issued.
Sources for this Lambeth basement extension page: borough policies maps and
conservation-area registers (2025–26), Royal Mail postcode district boundaries,
the Town and Country Planning (Fees for Applications) (England) Regulations, the Town
and Country Planning (General Permitted Development) (England) Order 2015 as amended,
and the Party Wall etc. Act 1996.
