BOROUGH · PROJECT

Rear extension in Haringey

Planning permission, real costs and what actually gets approved

Do you need planning permission for a rear extension in Haringey?

In most of Haringey, a single-storey rear extension within permitted development limits (3m on attached houses, 4m on detached, 4m height) can proceed without an application — the borough's Article 4 directions are localised to specific conservation areas rather than applied borough-wide, so much of the housing stock keeps full PD rights. Inside a conservation area, that basic single-storey rear allowance usually survives too; it's two-storey rear extensions and side elements that lose permitted development and need a full householder application. Always check the exact address: Haringey's protection is real, but it's drawn conservation area by conservation area, not applied across the whole borough.

PD carries many schemes in the east; Muswell Hill and Highgate need full applications.

Rear extensions are where Haringey's east-west contrast shows up most directly. In the borough's lighter-touch eastern streets, permitted development often carries the whole project, so the real work is a good drawn set and party wall notices rather than a planning argument. Move into the protected western conservation cores and the calculus changes: the single-storey rear allowance still generally applies, but you're now designing to sit comfortably on a Victorian or Edwardian streetscape that officers know well, and any hint of a second storey or side element pulls the scheme into a full application decided on precedent.

CHECK

What actually applies in Haringey

Conservation areas in Haringey

Real · planning.data.gov.uk

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

  • Bowes Park
  • Bruce Castle
  • Campsbourne Cottage Estate
  • Crouch End
  • Fortis Green
  • Highgate
  • Hillfield
  • Hornsey High Street
  • Hornsey Water Works & Filter Beds
  • Lordship Lane
  • Noel Park
  • Peabody Cottages
  • Rookfield
  • St Anns
  • Stroud Green
  • THRHC/Bruce Grove
  • THRHC/North Tottenham
  • THRHC/Scotland Green
  • THRHC/Seven Sisters/Page Green
  • THRHC/Tottenham Green
  • Tottenham Cemetery
  • Tower Gardens
  • Trinity Gardens
  • Vallance Road
  • Wood Green Common

…plus 5 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 Haringey

Real · planning.data.gov.uk

Article 4 directions in Haringey remove specific permitted development rights street by street — the single most common reason a "no permission needed" project turns out to need one.

  • Ashley Rd
  • Bounds Green Industrial Estate
  • Brantwood Road
  • Constable Crescent
  • Cranford Way
  • Cross Lane
  • Crusader Industrial Estate
  • Fountayne Rd
  • Hale Wharf
  • Herbert Rd/ Ashby Rd
  • High Road East
  • High Road West
  • Marsh Lane
  • Millmead & Lockwood
  • North East Tottenham
  • Omega Works
  • Queen Street
  • Rangemoor Rd
  • South Tottenham
  • Vale/ Eade Rd
  • Vale/ Tewkesbury Rd
  • White Hart Lane
  • Willoughby Lane
  • Wood Green

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

Average house price
£636,359
Annual change
-0.4%

Prices: HM Land Registry UK House Price Index, January 2026 · Open Government Licence.

How often Haringey grants householder applications: 90.9% of householder applications decided were granted (638 of 702) over 2025 Q2 to 2026 Q1 — rank 23 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 →
Haringey's mapped Article 4 footprint: 3.6% of the borough's area falls inside at least one of its 24 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 Haringey, 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 Haringey?

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 Haringey

The most common trip-up is assuming permitted development applies borough-wide and only discovering an Article 4 direction once drawings are done — always verify at the exact address rather than by neighbourhood reputation. In the conservation cores, brick match and roofline get close scrutiny, and validation can run slower than the standard eight weeks at busy periods, so build in buffer.

DISTRICTS

Postcode districts in Haringey

FAQ

Rear extension in Haringey, asked straight

01

Can I add a rear extension without planning permission in Tottenham or Wood Green?

Often, yes. Eastern Haringey carries lighter conservation designation than the west, so a single-storey rear extension within the standard permitted development limits frequently needs no application. That's a separate control from the borough's Article 4 direction covering house-to-HMO conversions in the east, which affects a different kind of change entirely — confirm your specific address regardless, since some eastern streets still sit inside conservation areas.
02

Does being in a conservation area rule out a rear extension in Haringey?

No — even inside one of Haringey's conservation areas, the basic single-storey rear extension allowance under permitted development generally survives. What conservation status removes is the two-storey and side-return versions, which need a full application judged on materials and roofline. Confirm the extent of your specific designation before assuming either way.
03

Why would a neighbour's identical rear extension have needed a full application when mine didn't?

Most likely because you sit on opposite sides of a conservation area boundary — Haringey's designations are drawn area by area rather than across the whole borough, so houses a few doors apart can face different regimes. It's also possible theirs was two-storey or included a side element, which loses permitted development even where a single-storey rear extension, like yours, keeps it.
04

How long does a rear extension take to get approved in Haringey?

A full householder application targets the statutory eight weeks, though Haringey's validation queue can run longer at busy periods, so build in buffer. A permitted development scheme moves faster still, especially with a Lawful Development Certificate confirming it rather than waiting to find out after the event.
05

Does it matter whether I'm in west or east Haringey for a rear extension?

Yes, more than in most of the boroughs we cover. The west carries the heavier conservation designation and closer design scrutiny; the east is lighter-touch, and permitted development carries more schemes there. The difference shows up in build outcomes and in what the finished extension is worth on either side of the borough.
CHECK

What applies at your address?

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

Free, and it stays free — no account, no payment. The check reads official geometry at the property's own coordinates; listed status, lease terms and the state of the building all sit outside it.

NEXT STEP

Who to talk to about a rear extension in Haringey

A rear extension is a design-and-consent job first: someone has to draw it and take it through Haringey's planning route. The neighbour, condition and party wall side is separate work and a different profession — which is why there are two doors here, not one.

Hampstead Chartered Surveyors & Building Consultancy
RICS-regulated · Firm Reg. 923064

Excavating foundations within 3m of a neighbour is notifiable — the surveyor serves the party wall notices.

  • Building surveys, RICS home surveys and defect diagnosis
  • Party wall matters and awards
  • Technical due diligence before a purchase
  • Leasehold and major-works advisory (Section 20)
  • Dilapidations and building pathology

Both practices are independent and separately regulated — Hampstead Chartered Surveyors & Building Consultancy is an RICS-regulated firm (Firm Reg. 923064); Hampstead Architecture and Planning are ARB-registered architects. We publish no fees for their work: each quotes directly for the job in front of them. Your enquiry goes to the practice you choose — we never pass your details to builders or other third parties.

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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