Not before you have obtained planning permission, if it is necessary. View information on planning.
48 hours after depositing all the information and charge necessary for a Building Notice application
You should avoid commencement of works until plans deposited under the Full Plans procedure have been approved.
If you choose to start works before a Full Plans application is approved, formal notices must be given and the work you do is done at your own risk until plans are approved.
Work which is exempt from control may be commenced once you have obtained any necessary planning consent.