BOROUGH

Planning permission in Hillingdon

Ruislip and Harefield villages to Heathrow and the Colne Valley; HMO and extension Article 4s.
Conservation areas
31
Article 4 areas
4
Average house price
£476,169
12-month change
+0.6%

Constraints: planning.data.gov.uk (ingested 2026-06-15) · Prices: HM Land Registry UK House Price Index, October 2025 · 187 sales in October 2025 · Open Government Licence

Planning in Hillingdonthe detail

Hillingdon is London's second-largest borough by area, running from the Metro-land suburbs of Ruislip, Eastcote and Northwood, through Uxbridge and Hayes, to Heathrow and the Colne Valley regional park on its western edge — much of it Green Belt. Its conservation areas protect a string of historic village cores — Ruislip Village, Eastcote Village, Harefield Village, Ickenham Village, Harmondsworth Village (with its medieval tithe barn) and Old Uxbridge — and the Eastcote Park and Northwood estates.

Hillingdon's Article 4 directions are unusually wide-ranging and recorded in the national dataset. They include a borough-wide HMO direction (requiring planning permission to convert a house to a small HMO), a direction removing the permitted development right to add residential extensions in defined areas, and directions controlling commercial-to-residential conversion and the demolition-and-rebuild of commercial buildings. The result is that the permitted-development fallback is removed in more situations here than in most boroughs.

Outside the conservation areas, Green Belt and Article 4 areas, much of Hillingdon's suburban stock keeps permitted development rights for rear extensions, side extensions and loft conversions. The address-level check is decisive — Green Belt, a conservation area, or one of the borough's several Article 4 directions can all change the route.

Policy detail lives in the Hillingdon local plan and applications are submitted via the Hillingdon planning portal.

Reviewed by
Savas Bulduk MRICSDirector, Hampstead Chartered Surveyors & Building Consultancy — RICS-regulated (Firm Reg. 923064)

Conservation areas in Hillingdon

Real · planning.data.gov.uk

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

  • Black Jacks Lock
  • Botwell: Nestles
  • Botwell: Thorn EMI
  • Bulls Bridge
  • Copper Mill Lock
  • Coppermill Lock
  • Cowley Church (St. Laurence)
  • Cowley Lock
  • Denham Lock
  • Eastcote (Morford Way)
  • Eastcote Park Estate
  • Eastcote Village
  • Harefield Village
  • Harlington Village
  • Harmondsworth Village
  • Hayes Village
  • Hillingdon Village
  • Ickenham Village
  • Longford Village
  • Northwood Town Centre, Green Lane
  • Northwood, Frithwood
  • Old Uxbridge / Windsor Street
  • Rockingham Bridge, Uxbridge
  • Ruislip Village
  • Ruislip, Manor Way
  • Springwell Lock
  • The Glen, Northwood
  • The Greenway
  • Uxbridge Moor
  • West Drayton Green
  • Widewater Lock

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

Article 4 directions in Hillingdon

Real · planning.data.gov.uk

Hillingdon's Article 4 directions are recorded in the national dataset and are unusually wide-ranging: a borough-wide HMO direction (planning permission to convert a house to a small HMO), a direction removing permitted development for residential extensions in defined areas, and directions controlling commercial-to-residential conversion and the demolition-and-rebuild of commercial buildings. Green Belt covers much of the borough's west. Use the area report, or the council's Article 4 register, for the direction that applies at a given address.

Source: planning.data.gov.uk · Open Government Licence · 4 directions recorded. Checked at address level by the area report.

PROJECTS

What gets built in Hillingdon

DISTRICTS

Hillingdon postcode by postcode

FAQ

Hillingdon planning, asked straight

01

Do I need planning permission to create an HMO in Hillingdon?

Yes. A borough-wide Article 4 direction now requires planning permission to convert a house (use class C3) into a small HMO (C4) anywhere in the borough, so the permitted-development shortcut for an HMO conversion no longer applies.
02

Could an Article 4 direction affect my Hillingdon extension?

It can — alongside the HMO direction, Hillingdon has an Article 4 direction that removes permitted development rights for residential extensions in defined areas, as well as directions controlling commercial-to-residential conversion. This means the permitted-development fallback is removed in more situations here than in most boroughs, so the address-level check matters.
03

Is my Hillingdon property in the Green Belt or a conservation area?

Either is possible — much of the borough's west, around the Colne Valley, is Green Belt, where building is tightly restricted, and the historic village cores (Ruislip, Eastcote, Harefield, Ickenham, Harmondsworth, Old Uxbridge) are conservation areas. The address check and the council's policies map confirm the designation.
04

Do I need planning permission for a rear extension or loft in Hillingdon?

Outside the conservation areas, Green Belt and any extension Article 4 area, much of Hillingdon's suburban stock keeps permitted development rights — a single-storey rear extension within the limits, or a rear-dormer loft within the volume limits, can often proceed under PD or prior approval. Given the borough's several Article 4 directions, check the address first.
05

How do I check constraints for a Hillingdon address?

Run the postcode through the Planning Permission Checker area report: it checks your coordinates against the official conservation-area and Article 4 geometry for Hillingdon and shows sold-price comparables, each cited to source — so you know the consent route before you commit to drawings.
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Related reading

CHECK

What applies at your address?

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

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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