You will need planning permission if you want to alter a building, piece of land or a permanent structure (such as a wall) and you need to carry out building work to do it. You will also need planning permission if your work will change the way the building or land is used.
More information on developments that need planning permission
More information on permitted developments
Apply for pre-application advice
Before submitting a planning application, we strongly recommend that you use the Pre-application advice service.
Pre-application planning enquiry (opens in new tab)How can I benefit from this service?
We can offer you specialist advice and knowledge on the various matters you need to consider before submitting an application. This will include:
- Clarifying which policies / standards/ factors apply to your development
- Helping you to submit an application that is complete, avoiding any delay during the registration / validation stage
- Advising you to prepare an application which, if you give full consideration to the advice provided, will speed up the process of determining your application
- Can lead to reducing the time taken by professional consultants and can save costs as they prepare the proposals
- Advising you if the principle of the development is unacceptable, therefore saving you the cost of applying
How does this work and what is the cost?
Large scale and complex applications
There is a different process with large scale and complex application. View details (opens in new tab)
Developments that need planning permission
You will usually need planning permission to:
- build a new building
- extend or alter an existing building
- make changes to the way a building is used, for example turning a house into flats or making an industrial building into a home
- undertake engineering work or other works, such as sewerage
- demolish a building or structure
- carry out work on a listed building
- carry out work in a conservation area
- carry out work on protected trees or trees in a conservation area
- build new agricultural buildings.
Permitted developments (where you don’t need planning permission)
There are some minor improvements, alterations and extensions you can make to your house that you don’t need planning permission for. These can include construction of some types of porch, glass conservatories under a certain size and also some internal changes.
Further guidance can be found on the Welsh Government's website.
If you are still unsure if you need planning permission you can get use our Pre-Application Advice service.