As a rule of thumb you can build an
orangery, conservatory or single story extension onto the back of your house without planning permission provided: The proposed extension plus any previous extensions don’t project more than 4m in the case of a detached property and 3m in the case of a semi-detached or terraced property.
There are several other factors which dictate the requirement for planning permission.
to find out more visit the official government planning portal: Visit Site/
