Basement plans in Bexley: 97% are decided by officers

Where in Bexley does a basement extension actually get determined?

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

How does a basement extension differ street by street across Bexley?

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

• Belvedere (DA17) — a basement extension in Belvedere starts from 1930s semi-detached, post-war flats, and Belvedere reads as 1930s semi-detached, post-war flats. 1930s houses were built without cellars in DA17. Bexley Council assesses Belvedere basement extensions against its own Belvedere character guidance, and the location plan we draw for Belvedere references Belvedere station.
• Barnehurst (DA7) — basement extension work in Barnehurst means 1930s semi-detached. Barnehurst is 1930s semi-detached. 1930s houses were built without cellars throughout DA7. Bexley Council decides the Barnehurst application, and Barnehurst station anchors the Barnehurst location plan.
• Bexleyheath (DA6, DA7) — a basement extension in Bexleyheath starts from 1930s semi-detached, and Bexleyheath reads as 1930s semi-detached. 1930s houses were built without cellars in DA6. Bexley Council assesses Bexleyheath basement extensions against its own Bexleyheath character guidance, and the location plan we draw for Bexleyheath references Bexleyheath Broadway.
• Sidcup (DA14, DA15) — basement extension work in Sidcup means 1930s semi-detached, edwardian villas. Sidcup is 1930s semi-detached, Edwardian villas. Edwardian houses rarely have a usable cellar throughout DA14. Bexley Council decides the Sidcup application, and Sidcup station anchors the Sidcup location plan.
• Welling (DA16) — basement extension work in Welling means 1930s semi-detached. Welling is 1930s semi-detached. 1930s houses were built without cellars throughout DA16. Bexley Council decides the Welling application, and Welling High Street anchors the Welling location plan.
• Erith (DA8) — Victorian terraces, post-war estates defines Erith, where victorian terraces, post-war estates set what a basement extension can do. Victorian cellars here convert without planning permission when the footprint and external appearance are unchanged across DA8. Any Erith basement extension is validated by Bexley Council, with Erith Riverside the usual Erith reference point on the site plan.
• Crayford (DA1) — a basement extension in Crayford starts from victorian terraces, 1930s semi-detached, and Crayford reads as Victorian terraces, 1930s semi-detached. Victorian cellars here convert without planning permission when the footprint and external appearance are unchanged in DA1. Bexley Council assesses Crayford basement extensions against its own Crayford character guidance, and the location plan we draw for Crayford references Crayford station.

How do conservation areas and Article 4 affect a basement extension in Bexley?

How designation changes a Bexley basement extension: Bexley Council maintains 16 conservation areas, including Crayford, Welling, Bexley Village. Inside any of them a Bexley basement extension cannot rely on permitted development, and the route becomes a £548 householder application determined in 8 weeks rather than a £249 prior approval in 6 weeks. Old Bexley sets the tone for Bexley casework.

Bexley permitted development status: there is no borough-wide direction from Bexley Council, so a basement extension at a DA1 address is normally still permitted development. We certify that with a £274 Lawful Development Certificate rather than leaving a Bexley sale to argue it later.

The building fabric around Bexley: 1930s semi-detached dominates; Victorian cottages in Bexley Village and Crayford; post-war estates in Thamesmead and Erith. Outer south-east London suburban; very permissive planning environment; strong PD uptake for extensions and loft conversions. A basement extension in Bexley is scoped against that stock first.

Which neighbouring authorities border Bexley?

• Greenwich — the Greenwich boundary runs against Bexley, so a basement extension a street from Bexley is decided by Greenwich Council instead. Greenwich runs 20 conservation areas across SE3 and its neighbours, which is why basement extensions priced for Bexley are re-checked against Greenwich policy whenever the Bexley address sits on that edge.
• Bromley — cross the Bexley boundary and Bromley Council takes the basement extension instead, applying 48 conservation areas of its own around BR1. We re-price basement extensions at the Bexley edge because Bromley policy and Bexley policy rarely align on basement extension depth.

Sources for this Bexley 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.