SW14 · Mortlake & East Sheen
SW14 covers Mortlake and Mortlake Green, the East Sheen Avenue and Sheen Lane conservation areas, and Sheen Common. Terrace and semi-detached stock makes side returns and lofts common, with conservation designation and the basement Article 4 the constraints that decide the route.
Location data: postcodes.io · Constraints: planning.data.gov.uk (borough-level) · Open Government Licence
Constraint context · Richmond upon Thames
Real · planning.data.gov.ukRichmond upon Thames has 86 designated conservation areas and 0 Article 4 areas. A district is too coarse to say which apply to your house — postcode districts span many streets and designations are drawn street by street. Enter a full postcode below for the point-level check, or read the full borough picture on the Richmond upon Thames planning guide.
Is SW14 in a conservation area?
Partly — and which part matters. A postcode district is never uniformly designated: SW14 contains 16 conservation areas within 1km of its centre, and whether your own property sits inside one decides whether permitted development survives. The centre point of SW14 itself falls inside Sheen Lane (Mortlake).
| Barnes Green | Nearby |
| Christ Church Road | Nearby |
| Cowley Road | Nearby |
| East Sheen Avenue | Nearby |
| Grove Park | Nearby |
| Holmesdale Avenue | Nearby |
| Model Cottages | Nearby |
| Mortlake | Nearby |
| Mortlake Green | Nearby |
| Queen's Road (Mortlake) | Nearby |
| Richmond Park | Nearby |
| Sheen Common Drive | Nearby |
| Sheen Lane (East Sheen) | Nearby |
| Sheen Lane (Mortlake) | At the centre |
| Thorne Passage | Nearby |
| White Hart Lane | Nearby |
Conservation areas whose official geometry lies within 1km of the centre of SW14. Source: planning.data.gov.uk · Open Government Licence. Proximity to the district centre is not a statement about your own address — run the address check for that.
Does an Article 4 direction apply in SW14?
The national dataset holds no Article 4 geometry within 1km of the centre of SW14. Treat that as unknown, not as “none”. The national dataset is known to omit property-specific directions, so the only safe answer is to verify on the council's own register for Richmond upon Thames before assuming a permitted-development right still exists.
Every designation in the borough: Richmond upon Thames planning guide →
Do you need planning permission in SW14?
Three routes exist, and which one you are on is decided by your address, not your postcode district:
| Permitted development — no application. The work stays inside the GPDO limits and no designation removes them. A Lawful Development Certificate is cheap proof for a future buyer. | No permission |
| Prior approval — the larger single-storey rear extension route, with neighbour consultation. Not available on designated land. | 42 days |
| Full householder application — required once a designation removes your permitted-development right, or the scheme exceeds the limits. | 8 weeks |
SW14 contains mapped conservation-area or Article 4 geometry, so a meaningful share of its streets will have lost some permitted-development rights — which pushes those properties onto the full-application route. Whether yours is one of them is an address-level question, not a district-level one.
What does planning permission cost in SW14?
| Householder planning application | £548 (from 1 April 2026) |
| Lawful Development Certificate — proposed works | £274 (half the application fee) |
| Lawful Development Certificate — existing works | £548 (the full application fee) |
| Listed building consent | No fee |
| Resubmission after a refusal | Free once, within 12 months of the decision |
National statutory figures for England — councils do not set them, so they are the same in every borough. Planning fees re-index every 1 April; confirm the current amount on the Planning Portal fee calculator before you apply. These are the council's fees only — drawings, surveys and any specialist reports are separate.
How long does it take?
| Householder application — statutory target | 8 weeks |
| Householder application — in practice | 8–12 weeks |
| Prior approval (larger home extension) | 42 days |
| Lawful Development Certificate | 8 weeks |
| Householder appeal — deadline to lodge | 12 weeks from the decision date |
| Householder appeal — typical decision | Around 18 weeks |
What if it's refused?
A refusal is a decision notice with reasons attached, and those reasons are a roadmap. Most homeowners in Richmond upon Thames — as anywhere in England — are better served by amending the scheme and using the free resubmission than by appealing: you get one further application on the same site within 12 months without paying again.
| Who can appeal | The applicant only — not neighbours |
| Fee to appeal | None — you bear your own costs |
| Procedure | Written representations for most householder appeals |
| Success rate | Roughly a third — about 36% of householder appeals allowed in 2025/26 |
Appeals go to the Planning Inspectorate, an independent national body. How to read a refusal and choose your route →
Planning permission by project in Richmond upon Thames
Single-storey rear extensions are unaffected by the basement Article 4, but conservation coverage is extensive — check whether the address sits in a designated area.
Rear extension in Richmond upon Thames →Common on the Victorian terraces of Richmond, Twickenham and Teddington; conservation designation decides whether it's PD or a full application.
Side return extension in Richmond upon Thames →Feasible on much of the suburban stock under PD; in the borough's many conservation areas, dormer form and a full application are the rule.
Loft conversion in Richmond upon Thames →A borough-wide Article 4 (since 2018) removes PD for basements except in the greatest flood-hazard areas — every basement here needs planning permission and flood-risk evidence.
Basement extension in Richmond upon Thames →PD allowances often apply on larger plots, but conservation-area designation (extensive here) removes them — and the structure must stay incidental and within height limits.
Garden room in Richmond upon Thames →Pinpoint your street
More of Richmond upon Thames
London's most conservation-dense borough; a borough-wide basement Article 4.
Borough page →Planning Permission Checker provides planning and cost intelligence for early feasibility only. It is not legal, planning, valuation, architectural, structural, or surveying advice. All estimates are indicative and must be verified by qualified professionals before purchase, design, planning submission, or construction.
Cost estimates are indicative only — not a quotation. Final price depends on survey, specification, structure, access, party wall matters, VAT, professional fees, and contractor availability.
Planning outcomes are not guaranteed. Local planning authorities make final decisions.