If you are wanting to carry out building work you must submit an application. There is a Full Plans application or Building Notice application.
The following will help you:
This is suitable for all projects. It requires the submission of plans, specification and other supporting documents. The proposals are checked to ensure compliance with Building Regulations and applicant or agent will be notified of any changes needed to the plans. An approval notice will be issued once all the information has been checked.
This is intended for small extensions, internal alterations and other minor work within dwelling houses. Detailed plans do not need to be submitted but other information may be asked for. If the proposal includes an extension to the building foot print a location plan to a scale of not less than 1:1250 is required.
You can pay for your Building Control application online
Building Control Application Form