A change of use of land or buildings will require planning permission if the change is considered ‘material’ (significant) in terms of its impact on the surrounding area. The local planning authority (LPA) decides whether or not a change of use is material but the general presumption is that a change from one use class to another or involving any sui generis use will constitute a material change of use (sui generis applies when a use of land and buildings does not fall within the standard defined use classes).
Planning permission is not needed when both the present and proposed uses fall within the same class (movement from one use to another within the same use class is not considered to be development). For example, there are 11 different uses within Class E ‘Commercial, Business and Service’ and changes between them are allowed to take place without the need for planning permission.
There are also certain permitted development rights that allow for some changes of use to occur between different use classes without having to apply for planning permission.