Permitted development rights are a narrow national grant for specific, limited works, while planning permission is the discretionary local application you need when works exceed those limits or local restrictions apply. If you are unsure which route covers your project, the safest first step is to check whether your property sits in an Article 4 area or a conservation area, then confirm the relevant size limits before you pick up a tool. Starting unauthorised work carries real enforcement risk, so a few minutes of checking now saves considerable stress later.
TL;DR:
- Most homeowners in Article 4 or conservation areas must seek planning permission for larger extensions, changes to principal elevations, or alterations affecting light and outlook.
- Permitted development rights generally allow small-scale projects like rear or loft extensions but can be revoked by local restrictions or previous extensions that use up your allowance.
- A prior approval is required for larger single-storey rear extensions, which involves neighbor consultation and potential conditions before starting work.
- A Lawful Development Certificate offers official confirmation that a project qualifies as permitted development, providing legal certainty before construction begins.
- Checking for local restrictions, past extensions, and specific size limits early can prevent costly mistakes like unauthorized work or invalid applications.
Table of Contents
- What planning permission is and when you need it
- What permitted development rights are and their key limits
- Comparing the two routes side by side
- Prior approval for larger single storey rear extensions
- Lawful Development Certificates and their fees
- How to decide which route to follow
- Practical next steps for Greater London projects
- A local view on common planning pitfalls
- LookDeVis Services: local support for prep and build works
- Authoritative resources to consult
- Sources
- FAQ
What planning permission is and when you need it
Planning permission is a formal application to your local planning authority, which assesses your proposal against its local plan, design standards and the impact on neighbouring amenity before deciding whether to grant consent. Unlike permitted development, it is discretionary: two similar projects on neighbouring streets can receive different outcomes depending on local context, sightlines and the character of the area.
Most homeowners need planning permission for two-storey or multi-storey side extensions, new dwellings, changes of use, and any alterations to a listed building. Works that significantly alter the principal elevation, or that would overshadow a neighbouring garden, also tend to fall outside permitted development and need a full application.
Timing varies by council and case load, and fees are set nationally with local variation for certain applications. The Gov sets out the conditions that must all be met for a project to qualify as permitted development rather than requiring an application. Carrying out work without the correct consent exposes you to enforcement action, which can include a requirement to alter or remove completed work at your own cost.
What permitted development rights are and their key limits
Permitted development rights are a national grant set out in the General Permitted Development Order, allowing specified works on dwellinghouses to go ahead without a full planning application, provided every condition attached to the relevant class is satisfied. Crucially, these rights generally apply to houses, not flats or maisonettes, so anyone in a converted flat should assume they need permission unless told otherwise by their council.
Common permitted development classes cover single-storey rear and side extensions, loft conversions, and outbuildings such as sheds or garden rooms, each with its own height, depth and footprint conditions. According to the Planning Portal, permitted development is not a blanket permission: even a project that appears to sit within the size limits can still fail if an Article 4 Direction removes the right locally, or if a previous extension already used up part of your allowance.
Conservation areas, Article 4 Directions, and homes created through a prior change of use often lose some or all permitted development rights. Building regulations and the Party Wall Act still apply even when planning permission is not required.
Comparing the two routes side by side
| Factor | Planning permission | Permitted development |
|---|---|---|
| Permission source | Local planning authority decision | National grant under the GPDO |
| Application required | Yes, full application | No, subject to prior approval in some cases |
| Typical scope | Larger extensions, new builds, change of use, listed buildings | House extensions, lofts, outbuildings within size limits |
| Local restrictions | Assessed case by case against local plan | Can be removed by Article 4 Directions or conservation status |
| Neighbour consultation | Yes, as part of the application process | Only where prior approval applies |
| Fees and timing | Standard planning fee, council-set timescale | Often no fee, or a lower fee for a certificate |
| Enforcement risk | High if work proceeds without consent | High if conditions or limits are misjudged |
A modest single-storey rear extension within the standard depth limits on a semi-detached house often proceeds under permitted development. A two-storey side extension on the same property, by contrast, usually needs a full planning application because of its scale and impact on neighbouring outlook. When in doubt, check for an Article 4 Direction and consider applying for a certificate or prior approval before committing to a design.
Prior approval for larger single storey rear extensions
Larger single-storey rear extensions sit in a middle category. According to the Planning Portal's prior approval guidance, detached houses can extend beyond the rear wall by a moderate to larger distance, and other houses by a slightly smaller amount, but only after a prior approval application is submitted and agreed before work begins.
The council will notify adjoining neighbours and consider their views on amenity grounds, such as loss of light or an overbearing impact. If neighbours raise a reasonable objection, the authority can refuse prior approval or attach conditions to the scheme. Starting work before prior approval is confirmed risks formal enforcement action, including a requirement to remove or alter the extension.
Lawful Development Certificates and their fees
A Lawful Development Certificate for proposed works gives you formal legal confirmation that a project qualifies as permitted development before you build it, which is useful when you want certainty rather than an assumption. According to GOV.UK's fee guidance, a certificate for proposed work typically attracts a fee that is around half of the standard full planning application fee, though you should check your local authority's published fee schedule for the exact figure.
A certificate is often a practical, cost-effective way to protect yourself against future disputes, particularly when you plan to sell the property and a buyer's solicitor asks for evidence that past work was lawful.
How to decide which route to follow
Working through a short sequence of checks before you commit to a design keeps risk low and avoids wasted architectural fees.
- Confirm whether your property is a house or a converted flat, since permitted development rights generally apply to houses only.
- Search your council's planning pages for an Article 4 Direction, conservation area designation or listed building status.
- Add up any previous extensions or loft work, since permitted development limits apply to the total enlargement of the dwelling, not just your current project.
- Check the specific limits and conditions for the relevant permitted development class before finalising dimensions.
- Decide whether you need prior approval, a Lawful Development Certificate, or a full planning application, and contact the local planning authority early if you are unsure.
Pro Tip: When your project alters the principal elevation or could affect a neighbour's light or outlook, applying for full planning permission gives you far more certainty than relying on a borderline permitted development reading.
For larger or technically complex schemes, bringing in a planning consultant or an experienced refurbishment team early can prevent costly redesigns later. Coordinating specialist input, including engaging plumbers and other trades early in a renovation, also helps you plan realistic timescales for the wider project.
Practical next steps for Greater London projects
Start with your borough's planning pages and the Planning Portal to check for Article 4 Directions, conservation area maps and any supplementary planning guidance affecting your street. Many boroughs publish interactive maps showing designated areas, which is the quickest way to confirm your starting position.
Before applying for prior approval or a certificate, gather site plans, elevation drawings and a summary of any previous extensions or alterations to the property. This paperwork speeds up assessment and reduces the chance of a request for further information.
Once consent is confirmed, preparing the site properly matters. Professional property service providers support London homeowners and developers with garden clearance, waste removal, tree surgery and refurbishment preparation ahead of extension or loft projects, helping the ground be ready when building work starts.
A local view on common planning pitfalls
The most frequent mistakes we see on London projects are skipping the Article 4 check, undercounting previous permitted development work against the total enlargement limit, and starting on site before prior approval or a certificate comes through. Early feasibility checks and the right paperwork consistently save homeowners time, cost and stress later in the project.
— Roman
LookDeVis Services: local support for prep and build works
Once your planning route is confirmed, professional property service teams can help with garden clearance, waste removal, tree work, pressure washing and refurbishment preparation across Greater London.
Ready to prepare your site? Request a free quote from LookDeVis Services and get your project moving.
Authoritative resources to consult
Always check your own borough's planning pages for Article 4 Directions and local supplementary planning documents before relying on general guidance.
Sources
FAQ
What is the 7 year rule for planning permission?
Unauthorised building work in England generally becomes immune from enforcement action after four years for operational development, or ten years for a change of use, rather than a single fixed seven-year rule. Rules on immunity are technical and case-specific, so check with your local planning authority before relying on any time limit.
What is allowed under permitted development in the UK?
Permitted development typically covers single-storey extensions, loft conversions and outbuildings on houses, provided each project meets the size, height and location conditions set out in the GPDO technical guidance. Flats, maisonettes and homes in Article 4 areas generally do not benefit from the same rights.
Can neighbours object to permitted development?
Neighbours cannot formally object to standard permitted development because no application is advertised, but they can raise concerns during the prior approval process for larger single-storey rear extensions. The Planning Portal's prior approval guidance confirms the council will consult adjoining neighbours before deciding on these larger schemes.
How high can I build under permitted development?
Height limits vary by project type and are set out class by class in the General Permitted Development Order, covering extensions, roof alterations and outbuildings separately. Because limits depend on your property type, boundary distance and any previous works, check the specific class conditions or ask your local planning authority before finalising a design.
Prices, timescales and information provided in this article are for general guidance and may vary depending on the property, site conditions, materials and scope of work. Please contact LookDeVis Services for an individual assessment and quotation. Where regulatory, planning or legal requirements apply, appropriate professional advice should be obtained.