Hillingdon Planning Consultant
Green Belt, Heathrow and a new plan
Hillingdon stretches from Harefield and Northwood in the north to Heathrow in the south, taking in Uxbridge, Hayes, West Drayton and Ruislip on the way. Few London boroughs combine so much Green Belt with an international airport, and that mix shapes almost every planning decision the council makes.
Cedar Planning is a Chartered practice led by Dan Malloy MRTPI. We work from Norfolk across England, London included, dealing with Hillingdon's planning team and the Planning Inspectorate and arranging site visits whenever a project needs one.
- RTPI Chartered
- Fixed-fee quotations
- Direct advice from a Chartered Planner
Hillingdon's two-part Local Plan and what replaces it
Planning decisions in Hillingdon rest on a Local Plan adopted in two stages. Part 1: Strategic Policies was adopted in 2012 and sets growth targets running to 2026. Part 2, made up of the Development Management Policies and the Site Allocations and Designations, was adopted on 16 January 2020. Both are read alongside the London Plan 2021.
The council has started again under the new plan-making system introduced by the Town and Country Planning (Local Planning) (England) Regulations 2026. It published its notice of intention to prepare a plan on 12 May 2026 and ran a scoping consultation from 9 July to 21 August 2026, with the first Gateway assessment timetabled for 17 September 2026.
The published timetable shows a consultation on the plan's content opening on 5 November 2026, a proposed plan in summer 2027, submission in November 2027 and adoption being considered in May 2028. Landowners with sites to promote should engage early, because the new system gives fewer chances to comment than the old one.
Until then, the 2020 policies do most of the work on applications. Their codes appear in nearly every officer report, so understanding which ones bite on a site is the first step in any Hillingdon project.
HMO controls extended across the borough
For years only the former Brunel and Uxbridge South wards needed permission for small HMOs. On 27 November 2025 Full Council approved an Article 4 Direction covering the whole borough, so conversions for three or more unrelated sharers will need planning permission. We check the in-force date against your timescale.
Planning issues particular to Hillingdon
Large parts of the north and west, including land around Harefield and the Colne Valley Regional Park, are Green Belt. Policy DMEI 4 applies to new buildings, extensions and changes of use there, alongside the national grey belt tests.
Policy DMAV 2 covers development at and around Heathrow, and DMAV 1 protects the safe operation of airports. Height, lighting, landscaping that attracts birds and noise exposure all need checking near the flight paths.
Policy DMAV 3 deals with RAF Northolt. Taller buildings, cranes and some uses near the airfield are referred to the Ministry of Defence for safeguarding comments before a decision.
A modified Class MA Article 4 Direction, in its current form since 27 March 2024, covers town centres, local parades, industrial land and the Hayes Opportunity Area. Many commercial to residential schemes need a full application.
How we help with Hillingdon projects
Every commission is quoted as a fixed fee once we understand the site. These are the services most often needed in Hillingdon.
Planning Applications
New homes, conversions and commercial schemes in Uxbridge, Hayes and West Drayton, prepared against Policy DMHB 11 on design and the London Plan housing standards.
View serviceHMO Planning Permission
Applications for small and large HMOs now that the borough-wide Article 4 Direction has been approved, addressing Policy DMH 5, room sizes, parking and concentration in the street.
View serviceFeasibility Studies
Early appraisals for sites in or near the Green Belt, under the flight paths or within the Heathrow and Hayes Opportunity Areas, so you know the constraints before paying for drawings.
View serviceLawful Development Certificates
Certificates confirming existing HMO use, outbuildings or extensions, which matter more as permitted development rights are withdrawn across the borough.
View serviceHeritage Statements
Assessments for listed buildings and conservation areas such as Harefield Village, Ruislip Village and Old Uxbridge, written to meet Policy DMHB 4 on conservation areas.
View serviceLocal Plan Representations
Submissions to each stage of the new Local Plan, starting with the content consultation expected in November 2026, for landowners with sites to promote.
View serviceThe policies that decide Hillingdon applications
The 2020 Development Management Policies are grouped by theme with prefixes. The DMHB series covers heritage and design, including DMHB 10 on high buildings and structures and DMHB 11 on the design of new development. The DMH policies deal with housing, DMEI with environment and infrastructure, and DMAV with aviation. Householder extensions fall under DMHD 1, and basements under DMHD 3.
The London Plan 2021 identifies two Opportunity Areas in Hillingdon. Heathrow, shared with Hounslow, has an indicative capacity of 13,000 homes, and Hayes, on the Elizabeth line corridor, of 4,000 homes. London Plan Policy G2 protects the Green Belt, and Policy D9 sets the tests for tall buildings.
Heathrow expansion is also moving. The government consulted on a draft Heathrow Expansion National Policy Statement between 18 June and 1 September 2026, based on a third runway. Its effect on land around Harmondsworth, Sipson and Longford will be a live issue for years.
Policy areas we work through in Hillingdon
The south of the borough, near Heathrow and the M4, has poor air quality. Larger schemes often need an assessment showing they are air quality neutral.
Tall schemes are tested for their effect on character, heritage and aviation safety. In Uxbridge and Hayes, heights are often negotiated storey by storey.
Rear, side and roof extensions must respect the host house and neighbours. Suburban streets in Ruislip, Ickenham and Eastcote tend to see close scrutiny of bulk.
Hillingdon's own CIL has applied since 1 August 2014, alongside the Mayoral CIL. A draft revised schedule, including new charges for data centres, went out for consultation in 2024.
A Consultancy That Works With You, For You
Hillingdon is two boroughs in one: a suburban and rural north controlled by Green Belt and heritage policy, and a southern belt around Heathrow and Hayes where growth, aviation and air quality dominate. The same proposal can be judged very differently depending on which side of the A40 or the M4 it sits.
With HMO controls widening and a new Local Plan starting, advice before submission helps avoid a refusal and shows whether a certificate, prior approval or full application is the right route.
RTPI Chartered
Led by a Chartered member of the Royal Town Planning Institute with more than ten years of public and private-sector planning experience.
Honest Prospects
A realistic view of the planning risks and options before you commit time or money.
Fixed, Transparent Fees
Fixed-fee quotations agreed before work starts, so you know the cost from the outset.
Direct Access
You deal with the Chartered Planner doing the work, not an account manager.
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Hillingdon Planning FAQs
Will I need planning permission for a small HMO in Hayes or Ruislip?
Once the borough-wide Article 4 Direction approved in November 2025 is in force, yes. Previously only Brunel and Uxbridge South wards were covered. If a property was already in lawful C4 use beforehand, a certificate can protect it. Our HMO Article 4 guide explains the process.
Can I extend a house that sits in Hillingdon's Green Belt?
Often, but the extension must not be disproportionate to the original building. Policy DMEI 4 and national policy both apply, and previous extensions count towards the total. Our Green Belt extensions guide covers the tests in more detail.
Does the Heathrow third runway affect planning decisions now?
The draft Heathrow Expansion National Policy Statement was consulted on in summer 2026 and has not been designated. Existing policies, including DMAV 2, still govern applications, but proposals close to the expansion area may face questions about safeguarding and future noise.
How can I put land forward for Hillingdon's new Local Plan?
The content consultation is timetabled to open on 5 November 2026 and close on 14 January 2027. That is the stage to submit site details and evidence. The new process has set gateways, so missing a window can be costly.
Can I convert an office in Uxbridge to flats without planning permission?
Possibly not. Hillingdon's modified Class MA Article 4 Direction covers town centres, employment locations and office growth areas, so many sites in Uxbridge need a full application. Outside the direction, prior approval may still be available, subject to the national conditions.
Get a Free Quote
Tell us what you are trying to achieve and where the property or site is. We will give you an initial view and a fixed-fee quote.
Or email us at info@cedarplanning.co.uk with the relevant information.
Planning a scheme in Uxbridge, Hayes or the Green Belt villages? Book a free 15-minute call, or read about feasibility studies and grey belt land.