You can apply for a Certificate of Design Compliance at two stages
You can apply for the CDC at two stages, either before (certified) or after (uncertified) you submit your building permit application.
1. Before applying for a building permit (Certified CDC application)
This is where a registered building surveyor certifies that your proposed designs comply with the relevant statutory requirements and issue the CDC before you lodge a building permit application
2. After applying for a building permit (Uncertified CDC application)
Here your authority certifies the designs after you’ve submitted a building permit application.