If you are planning to complete building works in NSW, you may need a Principal Certifier. Without a Principal Certifier (PC) you will be deemed to be carrying out unauthorised building work, and your local Council can stop work on the building. If work is stopped you will need to apply to Council for a Building Certificate to authorise the completed building work. You may also be required to modify your development consent and Construction Certificate. You may also be liable to a large fine under the EP&A Act.