You have the right to perform certain types of work on your dwelling without needing to apply for planning permission.
These rights are more restricted if you live in a conservation area or a listed building, and do not apply at all to flats, maisonettes or other buildings.
Commercial properties have different permitted development rights to dwellings.
Check your permitted development rights
Permitted development rights can be withdrawn by the planning authority, which means a planning application is needed.
This means that you need to check that the rights have not been withdrawn for your property before you begin work.
To find out if the authority has removed permitted development rights you will need to conduct a full back history search on the land or property, and view any planning permission decisions which will identify if the authority has removed any development rights.
For peace of mind, you can apply for a lawful development certificate. This provides proof that your building work is lawful. This is worth considering even if you are sure your project is permitted.