DA or CDC? How to tell which approval your Sydney project needs

Almost every building project in Sydney needs one of two approvals. A development application (DA) goes to your council, is assessed on its merits, and your neighbours are usually told about it. A complying development certificate (CDC) is issued by a private certifier or the council when a project meets a fixed set of state rules, and it is usually faster because nobody is weighing up whether they like it — they are checking it against a list.

Which one applies to me?

It depends on three things: what you want to build, where the property is, and what the block is like.

• What you want to build. New houses, alterations and additions, granny flats, some dual occupancies and many commercial fit-outs can qualify for a CDC if they stay inside the size, height and setback limits in the state code.
• Where it is. Heritage items and many heritage areas, some flood-prone land, some bushfire-prone land and certain other mapped areas are excluded from complying development. On those blocks the answer is a DA no matter how modest the project.
• What the block is like. Lot size, width at the building line, slope and existing buildings all decide whether the code's numbers can be met. Miss one number and the CDC pathway closes.

What people get wrong

The most expensive mistake is designing first and finding out the pathway afterwards. A scheme drawn for a CDC that turns out to need a DA often has to be redrawn, because the two pathways reward different things. The second most expensive mistake is assuming a CDC is "no approval": it is a full approval with its own conditions and inspections, and building outside it is unauthorised work.

How to find out in a day

Get a Section 10.7 planning certificate for the property from council (it lists the zone and the overlays that apply), check the zone against what you want to do, and then check the exclusions. If the block is in a heritage area or on a hazard map, stop there: it is a DA. If not, the project itself decides. We do this check before any drawing starts, and we tell you which pathway applies and why before you spend anything.