BOROUGH · PROJECT

Side return extension in Barking and Dagenham

Planning permission, real costs and what actually gets approved

Do you need planning permission for a side return extension in Barking and Dagenham?

Workable where terraces survive around Barking and Becontree; conservation areas need a full application. Side extensions have no permitted-development route inside a conservation area.

Workable where terraces survive around Barking and Becontree; the conservation areas need a full application.

Where continuous terrace stock exists, side returns follow the usual daylight, boundary and roof-junction tests under the Residential Extensions and Alterations SPD. On the dominant estate and semi stock, wrap-arounds with side access are often more natural than narrow alley infills.

CHECK

What actually applies in Barking and Dagenham

Conservation areas in Barking and Dagenham

Real · planning.data.gov.uk

Every designated conservation area in Barking and Dagenham from the official dataset — inside one, permitted development narrows and design scrutiny rises.

  • Abbey and Barking Town Centre Conservation Area
  • Abbey Road and Riverside Conservation Area
  • Chadwell Heath Anti-aircraft Gun Site Conservation Area
  • Dagenham Village Conservation Area

Source: planning.data.gov.uk · Open Government Licence. Boundaries are checked at address level by the area report.

Article 4 directions in Barking and Dagenham

Real · planning.data.gov.uk

Barking and Dagenham's Article 4 directions, partly recorded in the national dataset, include a borough-wide HMO direction (planning permission to convert a house to a small HMO), upward-extension directions in specific areas (recorded as the Dagenham Village and Lymington directions, removing the right to add a storey), and a direction controlling certain commercial-to-residential changes outside industrial land. The Residential Extensions and Alterations SPD sets householder design expectations. Check the council's Article 4 register for the direction that applies at a given address.

Source: planning.data.gov.uk · Open Government Licence · 3 directions recorded. Checked at address level by the area report.

Average house price
£358,039
Annual change
+0.8%

Prices: HM Land Registry UK House Price Index, December 2025 · Open Government Licence.

How often Barking and Dagenham grants householder applications: 68% of householder applications decided were granted (276 of 406) over 2025 Q2 to 2026 Q1 — rank 1 of 33 for lowest grant rate. London average: 85.6%. Householder applications are the class most side return extensions fall under. See the full householder approval-rate league table →
Barking and Dagenham's mapped Article 4 footprint: 100% of the borough's area falls inside at least one of its 3 named directions, including at least one that applies borough-wide— the single most common reason a side return extension that looks like permitted development turns out to need permission. See the full London Article 4 Coverage Index →
ROUTE

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.

LIMITS

Permitted development limits — side return extension

StoreysSingle storey only
Maximum height4m
Maximum widthNo wider than half the original house
Conservation areasSide 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 Barking and Dagenham, 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.

COST

How much does a side return extension cost in Barking and Dagenham?

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.

TIME

Realistic timeline

Design and drawings4–8 weeks
Planning decision8–12 weeks (8-week statutory target)
Party wall award (boundary wall works)6–10 weeks (parallel)
Build3–4 months
WATCH

What catches people out in Barking and Dagenham

Party wall procedure on a shared flank is unavoidable. Designing a wrap-around as pure permitted development is a common false start.

DISTRICTS

Postcode districts in Barking and Dagenham

FAQ

Side return extension in Barking and Dagenham, asked straight

01

Is a side return permitted development in Barking and Dagenham?

Only in limited cases outside conservation areas. Inside a conservation area, side extensions have no permitted-development route.
02

How much does a side return cost?

Expect £3,200–£4,800+ per m² — typically £45,000–£110,000 for a 9–15m² infill including structural opening, before VAT and fees.
03

What do officers focus on?

Boundary wall height, daylight to the neighbour, roof junction detail and materials.
04

Will I need a party wall agreement?

Almost certainly when building against or astride a shared boundary wall.
05

Does a neighbour's consent help?

Yes — matching consented depth on a similar house is strong evidence for a full application.
CHECK

What applies at your address?

Borough-level rules only narrow it down. Enter a Barking and Dagenham 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 Barking and Dagenham 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.

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