As well as being relatively easy to achieve planning permission, rear extensions are also a great way of adding value to your property.
In short, yes you will need to declare to the council that you are building an extension. However, as we've discussed previously the type of application you decide to go with, will be determined by the size of the extension and the wall it protrudes from.
Rear extensions which extend 3m or less from the original external rear wall can be built under what's known as permitted development. Under UK planning law properties have permitted development rights to develop certain types of external changes, without requiring planning permission. This includes new doors, windows and extensions. You can read more about this here in our article about what permitted development entails.
If the extension is to the side of the property and over half the width of the existing house; or if it's to the rear of the property and extends beyond 3m; or if it's in a conservation area or the area has an "article 4 direction" on it, you will have to submit what's called a householder planning application.
To find out more about UK planning law, or to discuss your project in more detail, why not call us today on 020 3538 1249