Do I Need Planning Permission? A Plain Guide
When common home projects need planning permission, what permitted development allows, and how building regulations and party wall rules fit in.
Before you knock through a wall, convert a garage or build a garden room, check what permission you need. Getting it wrong can mean costly changes later, problems when you sell or enforcement action from the council. This guide explains the basics for England. Rules differ in Wales, Scotland and Northern Ireland.
The quick answer
- Many house extensions and alterations fall under permitted development and need no planning application
- Flats and maisonettes usually do not have permitted development rights
- Conservation areas, listed buildings and Article 4 areas have tighter rules
- Building regulations usually still apply, even without planning permission
- Work on a shared wall may need a party wall agreement
What is permitted development?
Permitted development rights allow certain changes to a house without a planning application, as long as they stay within set limits on size, height, materials and position. The limits depend on the type of project and the type of house.
When permitted development may not apply
- Flats and maisonettes
- Listed buildings, which need listed building consent for many changes
- Conservation areas and other protected locations
- Areas where the council has made an Article 4 direction
- Properties where an earlier planning condition removed the rights
- New-build estates, where rights are sometimes restricted
Common projects at a glance
| Project | Planning permission | Building regulations |
| Single-storey rear extension | Often permitted development, within limits | Yes |
| Loft conversion | Often permitted development, within limits | Yes |
| Garage conversion | Often not needed if internal only | Yes |
| Garden room or outbuilding | Often permitted development, within size and use limits | Sometimes |
| Porch | Often permitted development, within size limits | Usually not |
| New driveway | Depends on surface and drainage | Usually not |
| Internal walls removed | Not usually for houses | Yes, if load-bearing |
| New kitchen or bathroom | Not usually | Sometimes, for drainage, ventilation or electrics |
This table is a general guide only. Always check the exact rules for your project and property.
Planning permission and building regulations are different
Planning permission controls what a building looks like and how it is used. Building regulations control how it is built: structure, fire safety, insulation, drainage, ventilation and electrics. Your local authority building control service or a registered building control approver (RBCA), where permitted for that type of work, oversees building control compliance.
Party walls
If you are working on or near a shared wall with a neighbour, such as a loft conversion, a rear extension or cutting into a party wall, the Party Wall Act may require you to give notice to your neighbours before you start.
How to check
- Use the Planning Portal's interactive house and common project guides
- Check your council's website for conservation areas and Article 4 directions
- Contact your council's planning team if you are unsure
- Consider a lawful development certificate, which proves your project is lawful and can help when you sell
Frequently asked questions
Do I need planning permission for a garage conversion?
Often not, if the work is internal and permitted development rights apply, but building regulations approval is needed.
Do I need permission for a garden office?
Often not, if it meets the size, height and position limits and is not used as separate living accommodation.
What is a lawful development certificate?
An official confirmation from the council that a project is lawful. It is not planning permission, but it gives peace of mind and helps when selling.
What happens if I build without permission?
The council can ask you to apply retrospectively, change the work or even remove it. It can also cause problems when you sell.
Planning a project?
Once permissions are sorted, we can help with the building and finishing work. Read our renovation planning guide, then send your plans, photos and postcode.
Official guidance and further reading
GOV.UK: registered building control approvers
Related guides
Prefer to talk? Call 07444 262522.