Planning Permission UK — Do You Need It?
Planning permission is one of the most confusing parts of home improvement. Some projects need it, some do not, and the rules depend on your property type, location, and what has been done before. This guide gives you the clear answer for the most common projects.
What Is Permitted Development?
Permitted development (PD) rights allow you to make certain changes to your home without applying for planning permission. Think of it as automatic planning permission for common improvements, subject to specific limits on size, height, and position.
PD rights can be removed in conservation areas, national parks, AONBs, or by conditions on your original planning permission. If your house was built with an Article 4 direction, some or all PD rights may not apply. Always check with your local planning authority before starting work.
Do You Need Planning Permission?
Usually NO planning permission needed
- Single-storey rear extension (up to 4m semi/terraced, 8m detached under prior approval)
- Loft conversion with rear dormer (within volume limits)
- Conservatory (within size limits)
- Garden shed, greenhouse, or summer house (under 2.5m near boundary)
- Replacing windows and doors (like-for-like)
- Internal alterations (non-structural in non-listed buildings)
- New driveway with permeable surface
- Solar panels (not on a listed building)
- Fences and walls under 2m (1m if next to a road)
- Decking under 30cm above ground level
Usually YES planning permission needed
- Two-storey extension over 3m deep
- Extension that exceeds PD volume or height limits
- Mansard loft conversion
- Any work on a listed building (even internal)
- Converting a house into flats
- Building a separate dwelling in the garden
- Change of use (residential to commercial)
- Work in a conservation area that alters the front or side
- Extension that covers more than 50% of the garden
- Balcony or raised platform over 30cm
How to Apply for Planning Permission
- Draw up plans. You need accurate drawings of the existing property and the proposed changes. An architect or architectural technologist will charge £1,000 – £3,000 for this.
- Submit online via the Planning Portal (planningportal.co.uk) or your local council website. You will need site plans, floor plans, elevation drawings, a design and access statement (for larger projects), and the application fee.
- Neighbour consultation. The council notifies your neighbours and puts up a site notice. There is typically a 21-day consultation period.
- Decision. The council aims to decide within 8 weeks for householder applications (13 weeks for major applications). They may approve, approve with conditions, or refuse.
- If refused: You can appeal to the Planning Inspectorate (free) or amend your plans and resubmit (another fee applies).
Planning Application Costs
| Application type | Fee (England, 2026) |
|---|---|
| Householder (extension, loft, etc.) | £206 |
| Listed building consent | £0 (free) |
| Lawful Development Certificate | £103 |
| Prior approval (larger extension) | £96 |
| New dwelling | £462 per dwelling |
Lawful Development Certificate (LDC)
Even if you do not need planning permission, it is worth getting a Lawful Development Certificate. This is official confirmation from the council that your project falls within permitted development. It costs £103 and provides proof when you come to sell that the work was legal.
Without one, a buyer’s solicitor may raise questions about whether the work had permission. This can delay or even derail a sale.
What Happens If You Build Without Permission?
The council can issue an enforcement notice requiring you to undo the work, even years later. There is no time limit for enforcement in some cases (listed buildings, for example).
For most other cases: If the work has been in place for 4 years (building work) or 10 years (change of use) without the council taking action, it becomes immune from enforcement. But this is risky — relying on the time limit is not a strategy.
When selling: Lack of planning permission or building regulations approval will be flagged by the buyer’s solicitor. You may need to pay for indemnity insurance, reduce the price, or even undo the work.
Tips for a Successful Application
Talk to your neighbours first. Objections from neighbours are the number one reason applications get refused. Discuss your plans before submitting.
Use pre-application advice. Most councils offer a paid pre-application service (£50 – £300) where a planner reviews your proposal informally before you submit. This can save you from submitting an application that will be refused.
Keep it in character. Extensions and alterations that match the style of the existing house and the surrounding area are much more likely to be approved.
Hire a good architect. Professional drawings and a well-written design statement make a real difference to the planning officer’s assessment.
Planning a project that adds value to your home? Use our Mortgage Calculator on CalcPad to see how much you could borrow against your increased property value.
Last updated May 2026. Planning rules vary by nation (England, Wales, Scotland, Northern Ireland) and by local authority. Always check with your local planning department.