Which postcode districts around Clapham do we cover for mansard roof extension work?
Every Clapham postcode district we draw in, the stock that dominates
it and the authority that validates a mansard roof extension there. Clapham 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 |
|---|
| SW4 | Clapham | Victorian terraces, Edwardian villas | SW4 straddles a boundary: Clapham addresses fall to Lambeth Council or Wandsworth Council, so confirm which authority validates the mansard roof extension before submitting SW4 drawings. |
| SW2 | Brixton | Victorian terraces, post-war estates | Neighbouring Brixton, where mansard roof extension work is handled by the same Lambeth Council case officers. |
| SE24 | Herne Hill | Victorian villas, Edwardian terraces | Neighbouring Herne Hill, 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. |
Which Clapham neighbourhoods suit a mansard roof extension best?
Roof pitch, wall build-up and plot depth change every few Clapham
streets, and each one changes what a mansard roof extension can achieve at that address.
- 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 Clapham: 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 Clapham: Streatham (SW16) — a mansard roof extension in Streatham starts from edwardian terraces, post-war flats, and Streatham reads as Edwardian terraces, post-war flats. Edwardian parapets give a mansard a clean base line in SW16. Lambeth Council assesses Streatham mansard roof extensions against its own Streatham character guidance, and the location plan we draw for Streatham references Streatham High Road.
- Near Clapham: Stockwell (SW9) — mansard roof extension work in Stockwell means victorian terraces, post-war estates. Stockwell is Victorian terraces, post-war estates. A mansard on a Victorian terrace almost always needs full planning permission throughout SW9. Lambeth Council decides the Stockwell application, and Stockwell station anchors the Stockwell location plan.
- Near Clapham: Vauxhall (SE11, SW8) — a mansard roof extension in Vauxhall starts from regency terraces, modern apartments, post-war flats, and Vauxhall reads as Regency fragments, riverside new-build. Mansards on post-war blocks are a structural and fire-strategy exercise before they are an aesthetic one in SE11. Lambeth Council assesses Vauxhall mansard roof extensions against its own Vauxhall character guidance, and the location plan we draw for Vauxhall references Vauxhall Bridge.
- Near Clapham: West Norwood (SE27) — Victorian terraces, Edwardian villas defines West Norwood, where victorian terraces, edwardian villas set what a mansard roof extension can do. A mansard on a Victorian terrace almost always needs full planning permission across SE27. Any West Norwood mansard roof extension is validated by Lambeth Council, with West Norwood Cemetery the usual West Norwood reference point on the site plan.
- Near Clapham: Tulse Hill (SE27, SW2) — mansard roof extension work in Tulse Hill means victorian villas, edwardian terraces. Tulse Hill is Victorian villas, Edwardian terraces. A mansard on a Victorian terrace almost always needs full planning permission throughout SE27. Lambeth Council decides the Tulse Hill application, and Tulse Hill station anchors the Tulse Hill location plan.
What local planning policy applies to a mansard roof extension in Clapham?
Clapham conservation designations: there are 64 across Lambeth Council, Herne Hill, Brixton Road, Kennington among them. Designation costs a Clapham owner the permitted-development route: a mansard roof extension then needs a £548 householder application over 8 weeks, in place of the £249 prior approval route that takes 6 weeks. Brixton Road is the Clapham designation that most often changes a mansard roof extension design.
What Article 4 removes near Clapham: Borough-wide Article 4 for HMO conversions; plus office-to-residential restrictions. Before pricing a mansard roof extension we check whether the SW4 address is inside the mapped area, because Lambeth Council draws the Clapham boundary street by street rather than across the whole of Clapham.
Clapham 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 mansard roof extension route in Clapham — construction, not postcode, sets what is achievable. Lambeth Council charges £548 for a householder application and has 8 weeks to determine it.
Who decides a mansard roof extension on the edge of Clapham?
- Southwark — adjoining Clapham, with 43 conservation areas centred on SE1. A mansard roof extension on the far side of the Clapham line is determined by Southwark Council, so the Clapham quote for mansard roof extensions is checked against Southwark guidance before it is issued.
- Wandsworth — adjoining Clapham, with 45 conservation areas centred on SW8. A mansard roof extension on the far side of the Clapham line is determined by Wandsworth Council, so the Clapham quote for mansard roof extensions is checked against Wandsworth guidance before it is issued.
- Croydon — cross the Clapham boundary and Croydon Council takes the mansard roof extension instead, applying 24 conservation areas of its own around CR0. We re-price mansard roof extensions at the Clapham edge because Croydon policy and Lambeth policy rarely align on mansard roof extension depth.
- Merton — cross the Clapham boundary and Merton Council takes the mansard roof extension instead, applying 28 conservation areas of its own around SW16. We re-price mansard roof extensions at the Clapham edge because Merton policy and Lambeth policy rarely align on mansard roof extension depth.
Sources for this Clapham 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.
