Council Authority Approvals
The fastest legitimate pathway to approval — when your project qualifies for CDC
A Complying Development Certificate (CDC) is a combined planning and construction approval that bypasses the traditional council DA process for eligible projects. Where a standard DA can take months to progress through council, a CDC issued by a private certifier can be granted in as little as ten business days for eligible residential projects. The key word is “eligible” — your project must comply with the applicable State Environmental Planning Policy (SEPP) and meet strict numerical standards relating to site coverage, setbacks, height, and other controls.
IA Engineering prepares the structural engineering documentation required to support your CDC application. We work in parallel with your architect and private certifier to produce drawings and reports that satisfy the certifier's technical requirements — prepared to the right level of detail and on the timeline your CDC process demands.
We have prepared CDC structural packages for single dwellings, dual occupancies, secondary dwellings, granny flats, swimming pools, decks, pergolas, and light commercial fitouts across greater Sydney and regional NSW. If your project is eligible for CDC, we can help you move fast.
CDC structural packages that get your approval moving
We prepare complete structural engineering documentation for your CDC application — coordinated with your certifier and tailored to the timeline a CDC requires. No over-engineering, no unnecessary delays.
- Structural drawings for private certifier
- CDC-compliant engineering documentation
- Fast turnaround for tight timelines
- All eligible project types
CDC structural package for a detached dual occupancy — prepared in parallel with the architectural plans to enable lodgement within the client's target timeline.
What makes CDC different from DA
The CDC pathway exists because NSW planning law recognises that many straightforward residential and low-impact commercial projects should not require the full council DA process. If your project meets the numerical standards set out in the relevant SEPP, a private certifier can issue the approval directly. The structural engineering input required for a CDC is different from a DA — it needs to be more detailed than a DA concept package, because the certifier is issuing a construction approval, not just a planning approval.
Faster Approval Timeline
For eligible projects, the CDC pathway is dramatically faster than a council DA. Under the Housing Code and the Low Rise Housing Diversity Code in NSW, private certifiers must determine a CDC application within ten business days for a single dwelling house, and twenty business days for a dual occupancy. Compare this with council DA timelines that routinely run three to six months for straightforward projects. The structural documentation must be ready when the application is lodged — which means your engineering team needs to be on board early and working to the certifier's timeline.
Private Certifier Pathway
A CDC is issued by an accredited private certifier, not by council. The certifier independently assesses whether the project complies with the applicable SEPP standards and the National Construction Code. For structural engineering, this means the certifier reviews your structural drawings and documentation — and if they are incomplete or unclear, the clock stops until the issue is resolved. IA Engineering prepares CDC structural packages that certifiers can assess without issuing further information requests, keeping your approval timeline on track.
Eligibility Requirements
Not every project can use the CDC pathway. The project must comply with the SEPP (Exempt and Complying Development Codes) 2008 — and the specific Code that applies (Housing Code, Low Rise Housing Diversity Code, Rural Housing Code, or Commercial and Industrial Code) has precise numerical requirements for setbacks, heights, floor space ratio, landscaped area, and other controls. If a project does not strictly comply with every applicable standard, it cannot proceed as CDC and must go through council DA. IA Engineering can advise whether your project's structural approach is consistent with CDC eligibility from the outset — before your architect invests significant time in a CDC design that may not qualify.
What the Structural Package Must Include
Unlike a DA, which requires only concept-level structural information, a CDC is a construction approval — so the structural documentation needs to be substantive. For a typical CDC project, IA Engineering prepares: a complete structural drawing set (foundation plan, floor framing plan, roof framing plan, and structural details); a structural design report including load calculations and design basis; and a design certificate signed by a Registered Professional Engineer (RPE). The certifier needs to be confident that the structural design complies with the NCC and Australian Standards before issuing the certificate.
“A well-prepared CDC package can get an eligible project approved in weeks instead of months. The structural documentation is usually what either enables that or slows it down.”
— IA Engineering Design Team
Projects eligible for CDC in NSW — and how we coordinate with your certifier
The most common CDC projects IA Engineering works on are single dwellings, detached dual occupancies, secondary dwellings (granny flats), swimming pools, and decks or pergolas attached to existing dwellings. Under the NSW Housing Code, these project types can be approved via CDC where they meet the applicable numerical development standards. Light commercial fitouts and low-impact industrial sheds may also be eligible under the Commercial and Industrial Code, depending on the specific works.
The coordination workflow for a CDC structural package differs from a DA. Because the private certifier is issuing a construction approval — not just a planning consent — the structural drawings need to be at a level where a builder can work from them. At the same time, because CDC timelines are tight, the documentation needs to be prepared and ready to lodge at the same time as the architectural plans. IA Engineering works in parallel with your architect from the early design stages to ensure the structural and architectural documentation is consistent and ready to lodge together.
We liaise directly with the private certifier throughout the process, responding to any technical queries about the structural documentation promptly to avoid approval delays. Where the certifier requires additional information or clarification, we address it directly and efficiently — the relationship between your engineer and your certifier matters, and we maintain those relationships across Sydney and NSW.
Eligible CDC project types:
- Single dwelling houses (new builds & alterations)
- Detached dual occupancies
- Secondary dwellings (granny flats)
- Swimming pools & associated structures
- Decks, pergolas & outbuildings
- Light commercial & industrial (where eligible)
Compliance & Standards
CDC structural documentation prepared in accordance with:
How we keep your CDC on schedule
The CDC pathway is fast — but only if all the required documentation is ready at lodgement. IA Engineering works to your timeline, preparing structural drawings and documentation in parallel with your architect so that the full package can be lodged together. We do not sit in a queue. When you engage us for a CDC project, we assign a structural engineer and get the design underway immediately.
We maintain direct communication with your private certifier from engagement through to approval. If the certifier has queries about the structural documentation, we respond directly and promptly — and where a revision is required, we turn it around fast. The certifier's ten or twenty business day clock stops if they issue a Request for Further Information, so resolving any structural queries quickly is a priority.
After CDC approval, IA Engineering remains available to provide structural engineering support during construction — including site inspections, structural certification of completed work, and responses to builder RFIs. Our involvement does not end at approval.