Single-storey rear extension in Clapham

Where in Clapham does a house extensions actually get determined?

Every Clapham postcode district we draw in, the stock that dominates it and the authority that validates a house extensions there. Clapham fees below are the statutory England rates for 2026, not house extensions estimates.

How does a house extensions differ street by street across Clapham?

Roof pitch, wall build-up and plot depth change every few Clapham streets, and each one changes what a house extensions can achieve at that address.

• Clapham (SW4) — house extensions work in Clapham means victorian terraces, edwardian villas. Clapham is Victorian terraces around the common. The side-return infill is the classic move on these Victorian terraces — 3 m of permitted development depth plus the width of the original side passage throughout SW4. Lambeth Council decides the Clapham application, and Clapham Common anchors the Clapham location plan.
• Near Clapham: Herne Hill (SE24) — house extensions work in Herne Hill means victorian villas, edwardian terraces. Herne Hill is Victorian villas around Brockwell Park. The side-return infill is the classic move on these Victorian terraces — 3 m of permitted development depth plus the width of the original side passage throughout SE24. Lambeth Council decides the Herne Hill application, and Brockwell Park anchors the Herne Hill location plan.
• Near Clapham: Kennington (SE11) — a house extensions in Kennington starts from georgian terraces, post-war estates, and Kennington reads as Georgian terraces, Regency squares. Georgian rear elevations here are usually the listed or locally listed face of the building in SE11. Lambeth Council assesses Kennington house extensions against its own Kennington character guidance, and the location plan we draw for Kennington references Kennington Park.
• Near Clapham: Streatham (SW16) — Edwardian terraces, post-war flats defines Streatham, where edwardian terraces, post-war flats set what a house extensions can do. Edwardian plots here are wider across SW16. Any Streatham house extensions is validated by Lambeth Council, with Streatham High Road the usual Streatham reference point on the site plan.
• Near Clapham: Stockwell (SW9) — house extensions work in Stockwell means victorian terraces, post-war estates. Stockwell is Victorian terraces, post-war estates. The side-return infill is the classic move on these Victorian terraces — 3 m of permitted development depth plus the width of the original side passage throughout SW9. Lambeth Council decides the Stockwell application, and Stockwell station anchors the Stockwell location plan.
• Near Clapham: Vauxhall (SE11, SW8) — house extensions work in Vauxhall means regency terraces, modern apartments, post-war flats. Vauxhall is Regency fragments, riverside new-build. Post-war houses on these estates often sit under an estate management scheme throughout SE11. Lambeth Council decides the Vauxhall application, and Vauxhall Bridge anchors the Vauxhall location plan.
• Near Clapham: West Norwood (SE27) — a house extensions in West Norwood starts from victorian terraces, edwardian villas, and West Norwood reads as Victorian terraces, Edwardian villas. The side-return infill is the classic move on these Victorian terraces — 3 m of permitted development depth plus the width of the original side passage in SE27. Lambeth Council assesses West Norwood house extensions against its own West Norwood character guidance, and the location plan we draw for West Norwood references West Norwood Cemetery.

Does Clapham planning policy restrict a house extensions?

Conservation areas covering Clapham: Lambeth Council runs 64, and Clapham Common, Herne Hill, Brixton Road are the ones Clapham owners meet most. A house extensions inside a Clapham conservation area loses permitted development, so the Clapham submission is a householder application at £548 decided in 8 weeks — not a £249 prior approval decided in 6 weeks. In Brixton Road a house extensions is judged on the street elevation first.

Clapham and Article 4: Borough-wide Article 4 for HMO conversions; plus office-to-residential restrictions. A house extensions planned at a SW4 address is checked against that direction first; Lambeth Council publishes the Clapham extent, and the SW4 line rarely follows the Clapham boundary you would expect.

The building fabric around Clapham: 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 house extensions in Clapham is scoped against that stock first.

Who decides a house extensions on the edge of Clapham?

• Merton — the Merton boundary runs against Lambeth, so a house extensions a street from Clapham is decided by Merton Council instead. Merton runs 28 conservation areas across SW16 and its neighbours, which is why house extensions priced for Clapham are re-checked against Merton policy whenever the Clapham address sits on that edge.
• Westminster — cross the Clapham boundary and Westminster City Council takes the house extensions instead, applying 56 conservation areas of its own around SW1. We re-price house extensions at the Clapham edge because Westminster policy and Lambeth policy rarely align on house extensions depth.
• Southwark — adjoining Clapham, with 43 conservation areas centred on SE1. A house extensions on the far side of the Clapham line is determined by Southwark Council, so the Clapham quote for house extensions is checked against Southwark guidance before it is issued.
• Wandsworth — the Wandsworth boundary runs against Lambeth, so a house extensions a street from Clapham is decided by Wandsworth Council instead. Wandsworth runs 45 conservation areas across SW8 and its neighbours, which is why house extensions priced for Clapham are re-checked against Wandsworth policy whenever the Clapham address sits on that edge.

Sources for this Clapham house extensions 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.