Where in Richmond upon Thames does a basement extension actually get determined?
Every Richmond upon Thames postcode district we draw in, the stock that dominates
it and the authority that validates a basement extension there. Richmond upon Thames fees below are the
statutory England rates for 2026, not basement extension estimates.
| Postcode | Area | Dominant stock | What it means for a basement extension |
|---|
| SW13 | Barnes | Georgian villas, Edwardian terraces | A basement extension at an SW13 address in Barnes is determined by Richmond Council under its own Local Plan policies for Barnes. |
| SW14 | Mortlake / East Sheen | Edwardian villas, 1930s semi-detached | SW14 covers Mortlake / East Sheen only; Richmond Council handles the basement extension. |
| TW1 | Twickenham | Georgian fragments, Victorian terraces, Edwardian villas | Twickenham sits wholly inside TW1, so Richmond Council validates every basement extension submitted from an TW1 address. |
| TW2 | Twickenham / Whitton | Georgian fragments, Victorian terraces, Edwardian villas | A basement extension at an TW2 address in Twickenham / Whitton is determined by Richmond Council under its own Local Plan policies for Twickenham / Whitton. |
| TW9 | Richmond / Kew | Georgian terraces, Victorian villas | A basement extension at an TW9 address in Richmond / Kew is determined by Richmond Council under its own Local Plan policies for Richmond / Kew. |
| TW10 | Richmond / Ham | Georgian terraces, Victorian villas | A basement extension at an TW10 address in Richmond / Ham is determined by Richmond Council under its own Local Plan policies for Richmond / Ham. |
| TW11 | Teddington | Edwardian villas, Victorian terraces | TW11 covers Teddington only; Richmond Council handles the basement extension. |
| TW12 | Hampton / Hampton Hill | Georgian villas, Edwardian terraces, 1930s semi-detached | Hampton / Hampton Hill sits wholly inside TW12, so Richmond Council validates every basement extension submitted from an TW12 address. |
What changes about a basement extension in each part of Richmond upon Thames?
Roof pitch, wall build-up and plot depth change every few Richmond upon Thames
streets, and each one changes what a basement extension can achieve at that address.
- Kew (TW9) — a basement extension in Kew starts from georgian and edwardian villas, and Kew reads as Georgian and Edwardian villas around the green. Georgian houses here already have a vault and a lower-ground floor in TW9. Richmond Council assesses Kew basement extensions against its own Kew character guidance, and the location plan we draw for Kew references Kew Gardens.
- Barnes (SW13) — Georgian and Edwardian village defines Barnes, where georgian villas, edwardian terraces set what a basement extension can do. Georgian houses here already have a vault and a lower-ground floor across SW13. Any Barnes basement extension is validated by Richmond Council, with Barnes Common the usual Barnes reference point on the site plan.
- East Sheen (SW14) — basement extension work in East Sheen means edwardian villas, 1930s semi-detached. East Sheen is Edwardian villas, 1930s semi-detached. Edwardian houses rarely have a usable cellar throughout SW14. Richmond Council decides the East Sheen application, and Sheen Lane anchors the East Sheen location plan.
- Teddington (TW11) — a basement extension in Teddington starts from edwardian villas, victorian terraces, and Teddington reads as Edwardian villas, Victorian terraces. Victorian cellars here convert without planning permission when the footprint and external appearance are unchanged in TW11. Richmond Council assesses Teddington basement extensions against its own Teddington character guidance, and the location plan we draw for Teddington references Teddington Lock.
- Hampton (TW12) — basement extension work in Hampton means georgian villas, edwardian terraces, 1930s semi-detached. Hampton is Georgian and Edwardian villages. Georgian houses here already have a vault and a lower-ground floor throughout TW12. Richmond Council decides the Hampton application, and Hampton Court Palace anchors the Hampton location plan.
- Whitton (TW2) — a basement extension in Whitton starts from 1930s semi-detached, and Whitton reads as 1930s semi-detached. 1930s houses were built without cellars in TW2. Richmond Council assesses Whitton basement extensions against its own Whitton character guidance, and the location plan we draw for Whitton references Whitton station.
- Ham (TW10) — basement extension work in Ham means georgian villas, post-war estates. Ham is Georgian common, post-war estate. Georgian houses here already have a vault and a lower-ground floor throughout TW10. Richmond Council decides the Ham application, and Ham Common anchors the Ham location plan.
What local planning policy applies to a basement extension in Richmond upon Thames?
Richmond upon Thames conservation designations: there are 72 across Richmond Council, Kew Green, Hampton Wick, Twickenham Riverside among them. Designation costs a Richmond upon Thames owner the permitted-development route: a basement extension then needs a £548 householder application over 8 weeks, in place of the £249 prior approval route that takes 6 weeks. Hampton Wick is the Richmond upon Thames designation that most often changes a basement extension design.
Richmond upon Thames permitted development status: there is no borough-wide direction from Richmond Council, so a basement extension at a SW13 address is normally still permitted development. We certify that with a £274 Lawful Development Certificate rather than leaving a Richmond upon Thames sale to argue it later.
The building fabric around Richmond upon Thames: Georgian in Richmond Green and Twickenham; Edwardian villas in Barnes and East Sheen; 1930s semi-detached in Whitton; riverside cottages along the Thames. Highest conservation area coverage in London; Royal Parks and Thames corridor add heritage layers; design quality heavily scrutinised. A basement extension in Richmond upon Thames is scoped against that stock first.
What happens if a Richmond upon Thames property sits on a boundary?
- Hounslow — adjoining Richmond upon Thames, with 30 conservation areas centred on W3. A basement extension on the far side of the Richmond upon Thames line is determined by Hounslow Council, so the Richmond upon Thames quote for basement extensions is checked against Hounslow guidance before it is issued.
- Kingston upon Thames — the Kingston upon Thames boundary runs against Richmond upon Thames, so a basement extension a street from Richmond upon Thames is decided by Kingston Council instead. Kingston upon Thames runs 22 conservation areas across KT1 and its neighbours, which is why basement extensions priced for Richmond upon Thames are re-checked against Kingston upon Thames policy whenever the Richmond upon Thames address sits on that edge.
- Wandsworth — cross the Richmond upon Thames 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 Richmond upon Thames edge because Wandsworth policy and Richmond upon Thames policy rarely align on basement extension depth.
- Hammersmith and Fulham — cross the Richmond upon Thames boundary and Hammersmith & Fulham Council takes the basement extension instead, applying 45 conservation areas of its own around W6. We re-price basement extensions at the Richmond upon Thames edge because Hammersmith and Fulham policy and Richmond upon Thames policy rarely align on basement extension depth.
Sources for this Richmond upon Thames 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.
