Basement under garden in Westminster

Which postcode districts around Westminster do we cover for basement under garden work?

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

How does a basement under garden differ street by street across Westminster?

Roof pitch, wall build-up and plot depth change every few Westminster streets, and each one changes what a basement under garden can achieve at that address.

• St John's Wood (NW8) — a basement under garden in St John's Wood starts from victorian villas, mansion blocks, and St John's Wood reads as Victorian villas, mansion blocks. Victorian cellars here convert without planning permission when the footprint and external appearance are unchanged in NW8. Westminster City Council assesses St John's Wood basement under gardens against its own St John's Wood character guidance, and the location plan we draw for St John's Wood references Lord's Cricket Ground.
• Bayswater (W2) — basement under garden work in Bayswater means victorian stucco terraces. Bayswater is Victorian stucco terraces. Victorian cellars here convert without planning permission when the footprint and external appearance are unchanged throughout W2. Westminster City Council decides the Bayswater application, and Hyde Park anchors the Bayswater location plan.
• Paddington (W2) — Regency and Victorian terraces, canal-side regen defines Paddington, where regency terraces, modern apartments set what a basement under garden can do. Modern foundations here are usually raft or piled across W2. Any Paddington basement under garden is validated by Westminster City Council, with Paddington Basin the usual Paddington reference point on the site plan.
• Victoria (SW1E, SW1W) — basement under garden work in Victoria means regency terraces, post-war flats. Victoria is Regency terraces, mixed-use. Post-war slab foundations make basements here expensive and rarely viable throughout SW1E. Westminster City Council decides the Victoria application, and Victoria Station anchors the Victoria location plan.
• Westbourne Green (W2, W9) — basement under garden work in Westbourne Green means victorian terraces, mansion blocks. Westbourne Green is Victorian terraces and mansion blocks. Victorian cellars here convert without planning permission when the footprint and external appearance are unchanged throughout W2. Westminster City Council decides the Westbourne Green application, and Royal Oak anchors the Westbourne Green location plan.
• Maida Vale (W9) — Edwardian mansion blocks, canal-side defines Maida Vale, where edwardian mansion blocks, victorian villas set what a basement under garden can do. Victorian cellars here convert without planning permission when the footprint and external appearance are unchanged across W9. Any Maida Vale basement under garden is validated by Westminster City Council, with Little Venice the usual Maida Vale reference point on the site plan.
• Mayfair (W1J, W1K) — Georgian listed townhouses, luxury defines Mayfair, where georgian townhouses, listed buildings set what a basement under garden can do. Georgian houses here already have a vault and a lower-ground floor across W1J. Any Mayfair basement under garden is validated by Westminster City Council, with Berkeley Square the usual Mayfair reference point on the site plan.

How do conservation areas and Article 4 affect a basement under garden in Westminster?

Westminster conservation designations: there are 56 across Westminster City Council, Marylebone, Pimlico, Soho among them. Designation costs a Westminster owner the permitted-development route: a basement under garden then needs a £548 householder application over 8 weeks, in place of the £249 prior approval route that takes 6 weeks. Covent Garden is the Westminster designation that most often changes a basement under garden design.

Article 4 and your Westminster basement under garden: Multiple Article 4 Directions — office-to-residential restrictions, HMO conversions, retail to residential in shopping zones. At a NW8 address that matters twice over, because Westminster City Council applies the direction unevenly across Westminster — we read the Westminster policies map for the exact NW8 address before quoting basement under gardens.

Digging below a Westminster property: Westminster basement policy restricts to single-storey, typically under 50% of rear garden footprint; lightwells and rooflights strictly controlled in conservation areas. Where a basement under garden in Westminster involves excavation that is read beside the Party Wall etc. Act 1996, which needs two months notice for a Westminster dig within 3 m of a neighbour, and Westminster City Council expects the NW8 ground conditions addressed in the application.

Westminster housing stock: Grand Georgian and Regency terraces in Belgravia and Pimlico; Victorian and Edwardian mansion blocks; heritage-rich townhouses throughout; very high listed building density. Heritage-first planning approach; listed buildings on almost every street; basement and rear extension policies particularly strict. Read that before choosing a basement under garden route in Westminster — construction, not postcode, sets what is achievable.

What happens if a Westminster property sits on a boundary?

• Camden — cross the Westminster boundary and Camden Council takes the basement under garden instead, applying 40 conservation areas of its own around NW1. We re-price basement under gardens at the Westminster edge because Camden policy and Westminster policy rarely align on basement under garden depth.
• Kensington and Chelsea — the Kensington and Chelsea boundary runs against Westminster, so a basement under garden a street from Westminster is decided by RBKC Planning instead. Kensington and Chelsea runs 38 conservation areas across SW1 and its neighbours, which is why basement under gardens priced for Westminster are re-checked against Kensington and Chelsea policy whenever the Westminster address sits on that edge.
• Wandsworth — adjoining Westminster, with 45 conservation areas centred on SW8. A basement under garden on the far side of the Westminster line is determined by Wandsworth Council, so the Westminster quote for basement under gardens is checked against Wandsworth guidance before it is issued.
• Lambeth — adjoining Westminster, with 64 conservation areas centred on SE1. A basement under garden on the far side of the Westminster line is determined by Lambeth Council, so the Westminster quote for basement under gardens is checked against Lambeth guidance before it is issued.

Sources for this Westminster basement under garden 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.