BOROUGH · PROJECT

Rear extension in Tower Hamlets

Planning permission, real costs and what actually gets approved

Do you need planning permission for a rear extension in Tower Hamlets?

On houses outside the conservation areas, a single-storey rear extension can often proceed under permitted development within the size limits. Inside the conservation areas — and throughout the listed Georgian stock of Spitalfields and Wapping — full applications and often listed building consent are the norm, with a high design bar. Tenure is the first filter: the borough is overwhelmingly flatted, and flats have no permitted development rights.

Houses outside the conservation areas can extend under PD; the Spitalfields and Wapping listed stock needs consent.

Tower Hamlets holds some of London's most significant heritage stock alongside dense flatted neighbourhoods and Docklands towers. The borough's Article 4 directions mostly protect town-centre commercial uses and control small house-to-HMO conversions — they are not householder extension restrictions — so conservation-area designation, listed status and the lease are what actually shape a rear extension. Where a house sits outside those heritage controls, standard rear extensions remain achievable under permitted development.

CHECK

What actually applies in Tower Hamlets

Conservation areas in Tower Hamlets

Real · planning.data.gov.uk

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

  • Albert Gardens
  • All Saints Church Pop.
  • Artillery Passage
  • Balfron Tower
  • Bethnal Green Gardens
  • Boundary Estate
  • Brickfield Gardens
  • Carlton Square
  • Chapel House
  • Clinton Road
  • Coldharbour
  • Commercial Road
  • Driffield Road
  • Elder Street
  • Fairfield Road
  • Fish Island
  • Ford Square
  • Ford Square and Sidney Square
  • Fournier Street
  • Globe Road
  • Hackney Road
  • Island Gardens
  • Jesus Hospital Estate
  • Langdon Park
  • Lansbury
  • Limehouse Cut
  • London Hospital
  • Lowell Street
  • Medway
  • Myrdle Street
  • Narrow Street
  • Naval Row
  • Old Bethnal Green Road
  • Redchurch Street
  • Regents Canal
  • Roman Road Market
  • Ropery Street
  • St Annes Church
  • St Frideswide's
  • St George in the East
  • St Mathias Church, Poplar
  • St Paul's Chuch
  • St Peter's
  • Stepney Green
  • Swaton Road
  • The Tower
  • Three Mills (part in Newham)
  • Tomlins Grove
  • Tower Hamlets Cemetery
  • Tredegar Square
  • Victoria Park
  • Wapping Pierhead
  • Wapping Wall
  • Wentworth Street
  • West India Dock
  • Whitechapel High Street
  • Whitechapel Market
  • Wiltons Music Hall
  • York Square

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

Article 4 directions in Tower Hamlets

Real · planning.data.gov.uk

Tower Hamlets' Article 4 directions, in this borough, mostly remove the right to convert town-centre commercial premises (Class E) to homes across around sixty named centres, and require planning permission to convert a house to a small HMO (C3 to C4) — they are not householder extension restrictions. For homeowners, conservation-area designation, listed status and (for flats) the lease are what matter; check the area report for a specific address.

Source: planning.data.gov.uk · Open Government Licence · 63 directions recorded. Checked at address level by the area report.

Average house price
£472,866
Annual change
-9.1%

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

How often Tower Hamlets grants householder applications: 92.1% of householder applications decided were granted (187 of 203) over 2025 Q2 to 2026 Q1 — rank 24 of 33 for lowest grant rate. London average: 85.6%. Householder applications are the class most rear extensions fall under. See the full householder approval-rate league table →
Tower Hamlets's mapped Article 4 footprint: 9.1% of the borough's area falls inside at least one of its 63 named directions— the single most common reason a rear 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?

Permitted development (GPDO Class A) covers single-storey rear extensions up to 3m beyond the original rear wall on attached houses and 4m on detached, with a maximum height of 4m. The 'larger home extension' route extends this to 6m/8m through prior approval with neighbour consultation — but that larger route is not available in conservation areas.

In conservation areas, the basic 3m/4m single-storey rear PD allowance usually survives — what conservation-area status removes is side extensions and two-storey rear extensions. An Article 4 direction can remove more, but Camden's directions in Hampstead and Belsize target front-and-side appearance (solar panels, window changes, boundary treatments), not the single-storey rear allowance. Flats have no PD rights at all. Two-storey rear extensions in conservation areas always need full permission.

Practical rule across London: check the address first. If a conservation area or Article 4 direction applies, budget for a full householder application decided on design, neighbour daylight (the 45-degree test) and materials.

LIMITS

Permitted development limits — rear extension

Single-storey rear depth — attached house3m beyond the original rear wall
Single-storey rear depth — detached house4m beyond the original rear wall
Larger extension via prior approval6m attached / 8m detached — not in conservation areas
Maximum height (single storey)4m
Two-storey rear in a conservation areaFull planning permission required
FlatsNo permitted development rights

Limits summarise the General Permitted Development Order (Schedule 2, Part 1) as it applies in London. In Tower Hamlets, 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 rear extension cost in Tower Hamlets?

Cost per m² (low — straightforward site)£3,000
Cost per m² (expected)£3,800
Cost per m² (high — conservation spec, hard access)£4,600+
Typical build cost (12–18m² single storey)£36,000 – £83,000
Professional fees, surveys, party wall (add)10–18% of build

Indicative London ranges calibrated from real project data. Conservation-area specifications (matching stock brick, lime mortar, bespoke glazing) and restricted rear access are the two biggest cost drivers. VAT not included.

TIME

Realistic timeline

Design and drawings4–8 weeks
Planning decision (full application)8–12 weeks (8-week statutory target)
Prior approval route, where available42 days
Party wall agreements4–10 weeks (parallel)
Build3–5 months
WATCH

What catches people out in Tower Hamlets

Starting design before confirming tenure and listing is the classic false start. On the Georgian and riverside heritage stock, unauthorised works to a listed building are a criminal offence — check first. For everyone else, flats and licence-to-alter requirements stop more projects than Article 4 ever does.

DISTRICTS

Postcode districts in Tower Hamlets

E1 — Whitechapel, Spitalfields & Wapping

E1 holds the borough's most significant heritage — the Fournier Street, Elder Street and Artillery Passage conservation areas of Spitalfields and the Wapping Pierhead and Wapping Wall waterfront.

E1 — Whitechapel, Spitalfields & Wapping →
E2 — Bethnal Green

E2 is the Boundary Estate — England's first council housing — plus the Old Bethnal Green Road, Jesus Hospital Estate and Globe Road conservation areas.

E2 — Bethnal Green →
E3 — Bow

E3 runs from the planned terraces of Tredegar Square and Driffield Road to the Roman Road Market conservation area and Victoria Park's edge.

E3 — Bow →
E14 — Isle of Dogs & Poplar

E14 spans Canary Wharf's towers, the Island Gardens and Coldharbour conservation areas and the Naval Row and West India Dock setting.

E14 — Isle of Dogs & Poplar →
E1W — Wapping

E1W is Wapping: the riverside strip running from the St Katharine's dock basins east towards the Shadwell edge.

E1W — Wapping →
FAQ

Rear extension in Tower Hamlets, asked straight

01

Do Tower Hamlets' Article 4 directions stop my rear extension?

Usually not. Most directions protect town-centre commercial uses or require permission for small HMO conversions. Conservation-area and listed status are what narrow householder options — the address check identifies those.
02

How much does a rear extension cost in Tower Hamlets?

Budget £3,000–£4,600+ per m², or roughly £36,000–£83,000 for a typical 12–18m² single-storey scheme, before VAT and fees. Listed and conservation-area specification sit at the top of the range.
03

Can I extend a flat in Tower Hamlets?

Only with planning permission and freeholder consent (a licence to alter). Flats have no permitted development rights, and with the borough overwhelmingly flatted this is the usual first question.
04

Will I need listed building consent in Spitalfields or Wapping?

Often yes on the Georgian and warehouse stock. Consent can be required for works affecting special character — including some internal alterations — on top of planning permission.
05

Do I need a party wall agreement?

On terraced and semi-detached houses, almost always. Serve notices early once drawings are fixed.
CHECK

What applies at your address?

Borough-level rules only narrow it down. Enter a Tower Hamlets postcode for the live constraint check — conservation area, Article 4 and sold-price comparables, cited to source.

Check a Tower Hamlets address

Need it in writing for one address? A planning permission report for a Tower Hamlets 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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