Side return extension in Bexley
Do you need planning permission for a side return extension in Bexley?
Workable where Victorian terraces survive in Erith and Bexleyheath; conservation designation decides permitted development versus a full application. In conservation areas, single-storey side extensions up to the boundary are often acceptable where the design matches the host house — but still need a full application.
Workable where Victorian terraces survive in Erith and Bexleyheath; conservation designation decides PD versus a full application.
True side-return stock is a smaller slice of Bexley than continuous inner-London belts. Where terraces exist, officers focus on matching materials and scale. On the dominant semis, wrap-arounds with side access are often more natural than narrow alley infills.
What actually applies in Bexley
Conservation areas in Bexley
Real · planning.data.gov.ukEvery designated conservation area in Bexley from the official dataset — inside one, permitted development narrows and design scrutiny rises.
- Brook Street
- Christ Church
- Crossness
- Erith Riverside
- Erith Road
- Foots Cray
- Halfway Street
- High Beeches
- Iron Mill Lane
- Lesney Park Road
- Longlands Road
- North Cray Village
- Oak Road
- Old Bexley
- Old Forge Way
- Parkhurst
- Red House Lane
- Star Hill
- The Green
- The Hollies
- The Oval
- Willersley Avenue and Braundton Avenue
- Woolwich Road
…plus 8 further designated areas.
Source: planning.data.gov.uk · Open Government Licence. Boundaries are checked at address level by the area report.
Article 4 directions in Bexley
Real · planning.data.gov.ukNo Article 4 geometry for Bexley appears in the national planning.data.gov.uk dataset, but the borough has operated a borough-wide HMO Article 4 direction since 24 September 2017, removing the right to convert a house to a small HMO (three to six occupants), plus householder directions in its conservation areas. Check the council's Article 4 pages for the position at a specific address.
Source: planning.data.gov.uk · Open Government Licence. Checked at address level by the area report.
Prices: HM Land Registry UK House Price Index, December 2025 · Open Government Licence.
The planning route — PD or permission?
Under permitted development, side extensions (GPDO Class A) must be single storey, no more than 4m high and no wider than half the original house — but side extensions are excluded from PD entirely in conservation areas. Wrap-around schemes combining side and rear elements usually exceed PD limits and need full permission everywhere.
In practice, most London side returns proceed by full householder application. The good news is the precedent base: on streets of identical terraces, a consented side return three doors down is the strongest evidence your scheme can cite. Officers focus on the boundary wall height, neighbour daylight and the junction with the host roof.
Permitted development limits — side return extension
| Storeys | Single storey only |
| Maximum height | 4m |
| Maximum width | No wider than half the original house |
| Conservation areas | Side extensions excluded from PD entirely |
| Wrap-around (side + rear combined) | Usually exceeds PD — full permission |
Limits summarise the General Permitted Development Order (Schedule 2, Part 1) as it applies in London. In Bexley, a conservation area, Article 4 direction or listed status changes the route — the panels above show what is designated, and the address check confirms what applies at your property.
How much does a side return extension cost in Bexley?
| Cost per m² (low) | £3,200 |
| Cost per m² (expected) | £4,000 |
| Cost per m² (high — wrap-around, conservation spec) | £4,800+ |
| Typical project (9–15m² incl. structural opening) | £45,000 – £110,000 |
| Professional fees, surveys, party wall (add) | 10–18% of build |
Side returns price higher per m² than plain rear extensions because steelwork, underpinning the party wall and roof glazing are spread over fewer metres. Indicative ranges from real project data; VAT excluded.
Realistic timeline
| Design and drawings | 4–8 weeks |
| Planning decision | 8–12 weeks (8-week statutory target) |
| Party wall award (boundary wall works) | 6–10 weeks (parallel) |
| Build | 3–4 months |
What catches people out in Bexley
Party wall procedure on a shared flank is unavoidable. Inside conservation areas, do not design as if permitted development still covers a side extension.
Postcode districts in Bexley
DA5 is Old Bexley — the historic village conservation area on the Cray, with Hall Place nearby and North Cray Village beyond.
DA5 — Bexley & Old Bexley →DA6 is Bexleyheath — the suburban town centre and the streets towards Danson Park.
DA6 — Bexleyheath →DA7 covers Barnehurst and northern Bexleyheath, near the Red House Lane conservation area around William Morris's Red House.
DA7 — Barnehurst & Bexleyheath →DA8 is Erith — the Erith Riverside and Erith Road conservation areas on the Thames.
DA8 — Erith →DA15 covers Sidcup and Lamorbey, including the Halfway Street conservation area.
DA15 — Sidcup →DA14 covers Sidcup and Foots Cray in Bexley — suburban semis and older village cores.
DA14 — Sidcup & Foots Cray →DA16 is Welling and East Wickham — interwar Bexley stock with a Greenwich edge.
DA16 — Welling & East Wickham →DA17 covers Belvedere and the Erith fringe in Bexley.
DA17 — Belvedere & Erith fringe →DA18 is Erith and Thamesmead East in Bexley — a mix of riverside regeneration, later estate stock and suburban streets.
DA18 — Erith & Thamesmead East →Side return extension in Bexley, asked straight
Is a side return permitted development in Bexley?
How much does a side return cost?
Can I extend up to the boundary in a conservation area?
Will I need a party wall agreement?
Does a neighbour's consent help?
What applies at your address?
Borough-level rules only narrow it down. Enter a Bexley postcode for the live constraint check — conservation area, Article 4 and sold-price comparables, cited to source.
Need it in writing for one address? A planning permission report for a Bexley property — from £59, or surveyor-reviewed from £295.
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.