Which Herne Hill postcodes does this mansard roof extension service cover?
Every Herne Hill postcode district we draw in, the stock that dominates
it and the authority that validates a mansard roof extension there. Herne Hill fees below are the
statutory England rates for 2026, not mansard roof extension estimates.
| Postcode | Area | Dominant stock | What it means for a mansard roof extension |
|---|
| SE24 | Herne Hill | Victorian villas, Edwardian terraces | A mansard roof extension in Herne Hill may land with Lambeth Council or Southwark Council — SE24 crosses the boundary, and the SE24 policies map decides it street by street. |
| SW4 | Clapham | Victorian terraces, Edwardian villas | Neighbouring Clapham, where mansard roof extension work is handled by the same Lambeth Council case officers. |
| SW2 | Brixton | Victorian terraces, post-war estates | Neighbouring Brixton, where mansard roof extension work is handled by the same Lambeth Council case officers. |
| SE11 | Kennington | Georgian terraces, post-war estates | Neighbouring Kennington, where mansard roof extension work is handled by the same Lambeth Council case officers. |
| SW16 | Streatham | Edwardian terraces, post-war flats | Neighbouring Streatham, where mansard roof extension work is handled by the same Lambeth Council case officers. |
| SW9 | Stockwell | Victorian terraces, post-war estates | Neighbouring Stockwell, where mansard roof extension work is handled by the same Lambeth Council case officers. |
| SE11 | Vauxhall | Regency terraces, modern apartments, post-war flats | Neighbouring Vauxhall, where mansard roof extension work is handled by the same Lambeth Council case officers. |
| SE27 | West Norwood | Victorian terraces, Edwardian villas | Neighbouring West Norwood, where mansard roof extension work is handled by the same Lambeth Council case officers. |
| SE27 | Tulse Hill | Victorian villas, Edwardian terraces | Neighbouring Tulse Hill, where mansard roof extension work is handled by the same Lambeth Council case officers. |
| SE1 | Waterloo | Georgian terraces, post-war flats, new-build | Neighbouring Waterloo, where mansard roof extension work is handled by the same Lambeth Council case officers. |
What changes about a mansard roof extension in each part of Herne Hill?
Roof pitch, wall build-up and plot depth change every few Herne Hill
streets, and each one changes what a mansard roof extension can achieve at that address.
- Herne Hill (SE24) — mansard roof extension work in Herne Hill means victorian villas, edwardian terraces. Herne Hill is Victorian villas around Brockwell Park. A mansard on a Victorian terrace almost always needs full planning permission throughout SE24. Lambeth Council decides the Herne Hill application, and Brockwell Park anchors the Herne Hill location plan.
- Near Herne Hill: Clapham (SW4) — mansard roof extension work in Clapham means victorian terraces, edwardian villas. Clapham is Victorian terraces around the common. A mansard on a Victorian terrace almost always needs full planning permission throughout SW4. Lambeth Council decides the Clapham application, and Clapham Common anchors the Clapham location plan.
- Near Herne Hill: Brixton (SW2, SW9) — Victorian terraces, vibrant centre defines Brixton, where victorian terraces, post-war estates set what a mansard roof extension can do. A mansard on a Victorian terrace almost always needs full planning permission across SW2. Any Brixton mansard roof extension is validated by Lambeth Council, with Brixton Market the usual Brixton reference point on the site plan.
- Near Herne Hill: Kennington (SE11) — Georgian terraces, Regency squares defines Kennington, where georgian terraces, post-war estates set what a mansard roof extension can do. Mansards read as original on Georgian terraces across SE11. Any Kennington mansard roof extension is validated by Lambeth Council, with Kennington Park the usual Kennington reference point on the site plan.
- Near Herne Hill: Streatham (SW16) — Edwardian terraces, post-war flats defines Streatham, where edwardian terraces, post-war flats set what a mansard roof extension can do. Edwardian parapets give a mansard a clean base line across SW16. Any Streatham mansard roof extension is validated by Lambeth Council, with Streatham High Road the usual Streatham reference point on the site plan.
- Near Herne Hill: Stockwell (SW9) — Victorian terraces, post-war estates defines Stockwell, where victorian terraces, post-war estates set what a mansard roof extension can do. A mansard on a Victorian terrace almost always needs full planning permission across SW9. Any Stockwell mansard roof extension is validated by Lambeth Council, with Stockwell station the usual Stockwell reference point on the site plan.
- Near Herne Hill: Vauxhall (SE11, SW8) — Regency fragments, riverside new-build defines Vauxhall, where regency terraces, modern apartments, post-war flats set what a mansard roof extension can do. Mansards on post-war blocks are a structural and fire-strategy exercise before they are across SE11. Any Vauxhall mansard roof extension is validated by Lambeth Council, with Vauxhall Bridge the usual Vauxhall reference point on the site plan.
Does Herne Hill planning policy restrict a mansard roof extension?
Conservation areas covering Herne Hill: Lambeth Council runs 64, and Clapham Common, Herne Hill, Brixton Road are the ones Herne Hill owners meet most. A mansard roof extension inside a Herne Hill conservation area loses permitted development, so the Herne Hill submission is a householder application at £258 decided in 8 weeks — not a £120 prior approval decided in 6 weeks. In Brixton Road a mansard roof extension is judged on the street elevation first.
Article 4 and your Herne Hill mansard roof extension: Borough-wide Article 4 for HMO conversions; plus office-to-residential restrictions. At a SE24 address that matters twice over, because Lambeth Council applies the direction unevenly across Herne Hill — we read the Herne Hill policies map for the exact SE24 address before quoting mansard roof extensions.
The building fabric around Herne Hill: 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. A mansard roof extension in Herne Hill is scoped against that stock first. Our Herne Hill fixed fee starts at £1,575; the £1,750 Complete package runs the Herne Hill scheme through Lambeth Council planning and building control in one go.
Who decides a mansard roof extension on the edge of Herne Hill?
- Merton — adjoining Herne Hill, with 28 conservation areas centred on SW16. A mansard roof extension on the far side of the Herne Hill line is determined by Merton Council, so the Herne Hill quote for mansard roof extensions is checked against Merton guidance before it is issued.
- Westminster — cross the Herne Hill boundary and Westminster City Council takes the mansard roof extension instead, applying 56 conservation areas of its own around SW1. We re-price mansard roof extensions at the Herne Hill edge because Westminster policy and Lambeth policy rarely align on mansard roof extension depth.
- Southwark — adjoining Herne Hill, with 43 conservation areas centred on SE1. A mansard roof extension on the far side of the Herne Hill line is determined by Southwark Council, so the Herne Hill quote for mansard roof extensions is checked against Southwark guidance before it is issued.
- Wandsworth — the Wandsworth boundary runs against Lambeth, so a mansard roof extension a street from Herne Hill is decided by Wandsworth Council instead. Wandsworth runs 45 conservation areas across SW8 and its neighbours, which is why mansard roof extensions priced for Herne Hill are re-checked against Wandsworth policy whenever the Herne Hill address sits on that edge.
Sources for this Herne Hill mansard roof 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.
