Planning Permission in Windsor and Maidenhead

Unitary Authority in South East · Last updated April 2026

The Royal Borough of Windsor and Maidenhead encompasses Windsor Castle, the River Thames, and a mix of historic towns and Green Belt countryside in east Berkshire. While the borough records zero designated conservation areas in the standard dataset, it contains 957 listed buildings and extensive Metropolitan Green Belt that fundamentally shapes planning decisions across the area.

Windsor's royal heritage and the Thames-side setting create a particularly sensitive planning context. The Green Belt designation covers the majority of the borough outside the built-up areas of Windsor, Maidenhead, and Ascot, restricting extensions and new development. The borough's approval rate of 68.4% is one of the lowest in England, reflecting the rigorous approach to protecting Green Belt and heritage.

The Royal Borough approved 68.4% of planning applications in the year ending September 2025, with 1,527 decisions from 1,716 applications — one of the busiest authorities in the region. Housing delivery at 95% meets the standard threshold.

0Conservation areas
1Article 4 directions
957Listed buildings
YesGreen belt

Planning a project in Windsor and Maidenhead? Start here.

Enter your address to check your permitted development rights, conservation area status, and Article 4 restrictions specific to Windsor and Maidenhead.

Free check — no account required

What can I build in Windsor and Maidenhead?

Project typeLikely permitted developmentMay need planning permissionLikely needs planning permission
Rear extension (single storey)Most of Windsor and MaidenheadProperties near boundaries or Green Belt fringe areaslisted buildings
Rear extension (two storey)Most of Windsor and Maidenhead, if within 3m limitCheck distance to boundary ≥7m or Green Belt fringe areaslisted buildings
Side extensionDetached houses outside protected zonesSemi-detached properties (half-width rule)listed buildings
Loft conversion (dormer)Houses outside conservation areasProperties on prominent corners or Green Belt fringe areaslisted buildings, flats
Loft conversion (Velux/rooflight)Most of Windsor and MaidenheadFront-facing rooflights in conservation areasListed buildings
Outbuilding / garden officeMost of Windsor and Maidenhead, if within size/height limitsLarge outbuildings covering >50% of gardenlisted buildings, Green Belt
PorchMost properties if within 3m² and 3m heightProperties near highway boundarylisted buildings
Solar panelsMost properties (roof-mounted)Panels protruding beyond rooflineListed buildings
Driveway / hard standingIf using permeable surfacingNon-permeable surfacing over 5m²Listed buildings with curtilage restrictions
Garage conversionMost of Windsor and Maidenhead (internal works)If changing external appearance significantlyListed buildings

This is general guidance based on Windsor and Maidenhead's planning constraints. Your specific property may differ — use our free PD checker to get a result tailored to your address.

Permitted development in Windsor and Maidenhead

Windsor and Maidenhead's permitted development framework is dominated by the extensive Metropolitan Green Belt, which covers much of the borough outside built-up areas. In the Green Belt, extensions must not be disproportionate to the original building, and new outbuildings are assessed against openness. Despite having no formally designated conservation areas in the standard dataset, the borough has locally designated heritage areas and the setting of Windsor Castle creates additional sensitivity. The 957 listed buildings mean many householders need listed building consent.

What Windsor and Maidenhead expects from your project

The Royal Borough's architectural character ranges from the grandeur of Windsor and Eton to the Thames-side villages and the modernising commercial centre of Maidenhead. Traditional materials include brick, flint, and tile. The council's design guidance emphasises high-quality design that respects the royal and riverside settings. In Windsor, development must be sensitive to the Castle's setting. In Maidenhead, the town centre regeneration supports contemporary architecture. Green Belt extensions should be subservient and use appropriate materials.

Local design guidance

Borough-wide Design Guide SPD

Key design policies
QP1QP3HO5
Local planBorough Local Plan (2022)
Royal Borough. Significant heritage constraints around Windsor Castle.

Local Plan: Royal Borough of Windsor and Maidenhead Local Plan

AdoptedFebruary 2022
Plan period2013-2033
Official documentView local plan →

The Royal Borough of Windsor and Maidenhead Local Plan was adopted in February 2022. It provides policies for an area with significant constraints including the Green Belt, Windsor Great Park and Windsor Castle. The plan allocates over 10,000 homes over the plan period.

68.4% approval rate

Windsor and Maidenhead's planning approval rate is below the national average of 86.9%. If your project needs planning permission, consider pre-application advice before submitting — it significantly reduces refusal risk.

Article 4 directions in Windsor and Maidenhead

1 Article 4 direction area

Class E to C3 Residential - Protected Employment Sites

Listed buildings in Windsor and Maidenhead

There are 957 listed buildings in Windsor and Maidenhead. If your property is listed, permitted development rights are significantly restricted. Most external and many internal alterations will require listed building consent, which is separate from planning permission. Always check with Windsor and Maidenhead's conservation team before starting any work on a listed property.

Planning application statistics

Year ending September 2025 | Source: MHCLG planning application statistics

68.4%Approval rate-18.5% vs national avg
1,716Applications received1,527 decided
94.1%Major decisions in time+3.3% vs national avg
92.2%Householder decisions in time-0.8% vs national avg
91%Non-major decisions in time+0.0% vs national avg
97.6%Delegated to officersNational avg 86.9% approval

Windsor and Maidenhead received 1,716 planning applications and decided 1,527 in the year ending September 2025. The approval rate of 68.4% is below the national average of 86.9%. Major applications are expected to be decided within 13 weeks, while householder and other non-major applications have an 8-week target. The “in time” figures include decisions made within agreed extensions of time.

Windsor and Maidenhead approved just 68.4% of applications in the year ending September 2025 — one of the lowest rates in England — with a 97.6% delegation rate. Major applications achieved 94.1% on-time performance, with householder at 92.2%. The council processed 1,527 decisions from 1,716 applications, including 983 householder decisions — one of the highest volumes in the region. Housing delivery at 95% meets the standard threshold.

If your project complies with permitted development rules, you don't need to worry about approval rates — a Lawful Development Certificate is a factual assessment, not a judgment call.

Recent planning applications in Windsor and Maidenhead

Browse what's been approved near you

Seeing what similar projects have been approved near your property can help you understand what Windsor and Maidenhead expects in terms of scale, materials, and design. It's also useful for gauging how quickly the council processes applications.

Search planning applications on Windsor and Maidenhead's portal →

Data from MHCLG planning application register. Search for householder applications (H01/H02) to see extensions and loft conversions in your area.

Housing delivery in Windsor and Maidenhead

Housing Delivery Test 2023 measurement | Source: MHCLG

95%Housing Delivery Test resultNo consequences
934Homes required (3 years)
884Homes delivered (3 years)

Windsor and Maidenhead delivered 884 homes against a requirement of 934 over the three-year measurement period, giving a Housing Delivery Test score of 95%. This is above the 95% threshold, which means there are no government-imposed consequences for housing under-delivery. Planning applications in Windsor and Maidenhead are assessed on their own merits under standard planning policies.

Lawful Development Certificates in Windsor and Maidenhead

A Lawful Development Certificate (LDC) is formal confirmation from Windsor and Maidenhead that your project is lawful under permitted development rules. It is not legally required before you build, but it is the only official document that proves your project did not need planning permission. Most solicitors will ask for one when you come to sell, remortgage, or insure your property.

983Householder PD applications decidedYear ending September 2025
92.2%Decided within 8 weeks-0.8% vs national avg
68.4%Overall approval rate-18.5% vs national avg
£258Application feeSame fee for proposed and existing development
8 weeksDetermination periodStatutory target for Windsor and Maidenhead to decide
NoNeighbour consultationLDC applications are not advertised or consulted on

Windsor and Maidenhead decided 983 householder applications in the year ending september 2025. Their 8-week performance of 92.2% is below the national average of 93%, so LDC applications may take longer than the 8-week target. LDC applications follow the same 8-week statutory determination period as householder planning applications.

How to apply for an LDC in Windsor and Maidenhead

You can apply for a Lawful Development Certificate through the Planning Portal or directly through Windsor and Maidenhead's website. You will need to submit:

  • A completed application form (available on the Planning Portal)
  • A site location plan at 1:1250 or 1:2500 scale
  • Existing and proposed floor plans and elevations
  • A written description of the proposed works and how they comply with the GPDO 2015
  • The application fee of £258

Windsor and Maidenhead must issue a decision within 8 weeks. If the application is approved, the certificate is a permanent legal record that the development is lawful. If refused, you can appeal to the Planning Inspectorate or amend your project and reapply.

Need help preparing your LDC application?

Our Permitted Development Certificate Report gives you a full PD eligibility assessment, property constraints check, and application checklist tailored to your address and project — so you can apply with confidence.

Pre-application advice in Windsor and Maidenhead

Windsor and Maidenhead offers a pre-application advice service. The fee for householder pre-app advice is From £100 for householder proposals.

Pre-app advice is worth paying for if your project is borderline, your property is in a conservation area, or your home is a listed building.

Think your project might be permitted development?

Check in 2 minutes with our free tool — no sign-up needed.

Check your PD rights now →

Pre-application advice for householder and commercial developments within the Royal Borough.

View Windsor and Maidenhead's pre-application advice page →

Planning fees and timelines in Windsor and Maidenhead

Application typeFeeTypical timeline
Householder planning application£5288 weeks
Full planning permission£610 per dwelling8-13 weeks
Lawful Development Certificate (proposed)£2646-8 weeks
Lawful Development Certificate (existing)£2986-8 weeks
Listed building consentFree8 weeks
Prior approval£12056 days
Discharge of conditions£145 per request8 weeks
Non-material amendment£4428 days

Fees are set nationally and correct as of April 2026. Pre-application fees are set by Windsor and Maidenhead and may change. Building regulations fees are separate — see the building control section below.

Building regulations in Windsor and Maidenhead

Building regulations approval is separate from planning permission. Most extensions, loft conversions, and structural alterations need building regs approval even if they don't need planning permission.

Building control in Windsor and Maidenhead is provided by RBWM Building Control. You can also use a private approved inspector instead of the council's service.

Windsor and Maidenhead planning department

AddressRoyal Borough of Windsor and Maidenhead, Town Hall, St Ives Road, Maidenhead, SL6 1RF
Office hoursMonday to Friday, 8:30am - 5:00pm
Planning policyView planning policies

Your building project checklist for Windsor and Maidenhead

  1. Check if your property is in a conservation area Use our free checker to find out.
  2. Check for Article 4 directions at your address Windsor and Maidenhead has 1 Article 4 areas. Check your address.
  3. Check if your property is listed search the Historic England list.
  4. Use our free PD checker to see if your project qualifies as permitted development Check now.
  5. Consider a Lawful Development Certificate if PD applies — it protects you when selling. Learn more about LDCs or get your PD Certificate Report.
  6. Consider pre-application advice if planning permission is needed — see the pre-application section above.
  7. Check building regulations — most extensions and loft conversions need building regs approval even if they don't need planning permission.
  8. Check Party Wall Act obligations if building near a boundary — read our Party Wall guide or use our free Party Wall tool.
  9. Notify your home insurer about planned building work.
  10. Get at least 3 quotes from builders and check their credentials.

Stay informed about planning in Windsor and Maidenhead

Approval rate updates, Article 4 changes, and local planning tips — straight to your inbox.

No spam. Unsubscribe anytime.

Frequently asked questions