Which postcode districts around Ealing do we cover for basement extension work?
Every Ealing postcode district we draw in, the stock that dominates
it and the authority that validates a basement extension there. Ealing fees below are the
statutory England rates for 2026, not basement extension estimates.
| Postcode | Area | Dominant stock | What it means for a basement extension |
|---|
| W4 | Chiswick / Bedford Park | Arts & Crafts villas (listed) | Chiswick / Bedford Park is split at W4. Either Hounslow Council or Ealing Council can determine a basement extension here, so the W4 address is checked against both policies maps first. |
| W3 | Acton | Victorian and Edwardian terraces | W3 straddles a boundary: Acton addresses fall to Ealing Council or Hounslow Council, so confirm which authority validates the basement extension before submitting W3 drawings. |
| W5 | Ealing | Edwardian villas, Victorian terraces | A basement extension at an W5 address in Ealing is determined by Ealing Council under its own Local Plan policies for Ealing. |
| W7 | Hanwell | Edwardian villas, 1930s semi-detached | Hanwell sits wholly inside W7, so Ealing Council validates every basement extension submitted from an W7 address. |
| W13 | West Ealing | Edwardian terraces | West Ealing sits wholly inside W13, so Ealing Council validates every basement extension submitted from an W13 address. |
| UB1 | Southall North | Edwardian terraces, post-war flats | Southall North sits wholly inside UB1, so Ealing Council validates every basement extension submitted from an UB1 address. |
| UB2 | Southall South | Edwardian terraces, post-war flats | A basement extension at an UB2 address in Southall South is determined by Ealing Council under its own Local Plan policies for Southall South. |
| UB5 | Northolt | 1930s semi-detached, post-war estates | Northolt sits wholly inside UB5, so Ealing Council validates every basement extension submitted from an UB5 address. |
What changes about a basement extension in each part of Ealing?
Roof pitch, wall build-up and plot depth change every few Ealing
streets, and each one changes what a basement extension can achieve at that address.
- West Ealing (W13) — a basement extension in West Ealing starts from edwardian terraces, and West Ealing reads as Edwardian terraces. Edwardian houses rarely have a usable cellar in W13. Ealing Council assesses West Ealing basement extensions against its own West Ealing character guidance, and the location plan we draw for West Ealing references West Ealing station.
- Southall (UB1, UB2) — basement extension work in Southall means edwardian terraces, post-war flats. Southall is Edwardian terraces, post-war estates. Edwardian houses rarely have a usable cellar throughout UB1. Ealing Council decides the Southall application, and Southall Broadway anchors the Southall location plan.
- Greenford (UB6) — basement extension work in Greenford means 1930s semi-detached. Greenford is 1930s semi-detached. 1930s houses were built without cellars throughout UB6. Ealing Council decides the Greenford application, and Greenford station anchors the Greenford location plan.
- Northolt (UB5) — basement extension work in Northolt means 1930s semi-detached, post-war estates. Northolt is 1930s semi-detached, post-war estates. 1930s houses were built without cellars throughout UB5. Ealing Council decides the Northolt application, and Northolt Tube anchors the Northolt location plan.
- Bedford Park (W4) — basement extension work in Bedford Park means arts & crafts villas (listed). Bedford Park is Arts & Crafts garden suburb, conservation. Victorian cellars here convert without planning permission when the footprint and external appearance are unchanged throughout W4. Ealing Council decides the Bedford Park application, and Bedford Park Estate anchors the Bedford Park location plan.
- Pitshanger (W5) — Edwardian conservation area defines Pitshanger, where edwardian villas set what a basement extension can do. Edwardian houses rarely have a usable cellar across W5. Any Pitshanger basement extension is validated by Ealing Council, with Pitshanger Lane the usual Pitshanger reference point on the site plan.
- Park Royal (NW10) — industrial fringe, new residential defines Park Royal, where modern apartments, post-war estates set what a basement extension can do. Post-war slab foundations make basements here expensive and rarely viable across NW10. Any Park Royal basement extension is validated by Ealing Council, with Park Royal station the usual Park Royal reference point on the site plan.
Does Ealing planning policy restrict a basement extension?
Ealing conservation designations: there are 30 across Ealing Council, Bedford Park, Acton Green, Hanwell among them. Designation costs a Ealing 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. Ealing Broadway is the Ealing designation that most often changes a basement extension design.
What Article 4 removes near Ealing: Article 4 for HMOs in specific streets in Acton, Ealing and Southall. Before pricing a basement extension we check whether the W3 address is inside the mapped area, because Ealing Council draws the Ealing boundary street by street rather than across the whole of Ealing.
Ealing housing stock: Victorian and Edwardian villas in Ealing central; 1930s semi-detached in Northolt and Hanwell; mansion blocks along main roads; Bedford Park is a listed Arts & Crafts garden suburb. Leafy outer-west London; Bedford Park conservation area has strict heritage controls; rest of borough generally permissive. Read that before choosing a basement extension route in Ealing — construction, not postcode, sets what is achievable.
What happens if a Ealing property sits on a boundary?
- Hounslow — adjoining Ealing, with 30 conservation areas centred on W3. A basement extension on the far side of the Ealing line is determined by Hounslow Council, so the Ealing quote for basement extensions is checked against Hounslow guidance before it is issued.
- Hillingdon — the Hillingdon boundary runs against Ealing, so a basement extension a street from Ealing is decided by Hillingdon Council instead. Hillingdon runs 29 conservation areas across HA4 and its neighbours, which is why basement extensions priced for Ealing are re-checked against Hillingdon policy whenever the Ealing address sits on that edge.
- Brent — adjoining Ealing, with 22 conservation areas centred on NW2. A basement extension on the far side of the Ealing line is determined by Brent Council, so the Ealing quote for basement extensions is checked against Brent guidance before it is issued.
- Hammersmith and Fulham — the Hammersmith and Fulham boundary runs against Ealing, so a basement extension a street from Ealing is decided by Hammersmith & Fulham Council instead. Hammersmith and Fulham runs 45 conservation areas across W6 and its neighbours, which is why basement extensions priced for Ealing are re-checked against Hammersmith and Fulham policy whenever the Ealing address sits on that edge.
Sources for this Ealing 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.
