A complying development certificate (CDC) is issued only once the drawings prove, line by line, that a design meets the relevant code. In our experience, most hold-ups are not caused by bad designs. They come from plans that leave out key information or say two different things at once.
Heights drawn without real ground levels
The Housing Code measures building height from existing ground level, meaning the ground as it sits before any digging or filling. If the elevations show a neat flat ground line but the block actually falls away, the certifier cannot confirm the height of the building or of each wall.
That matters twice over, because the code's side and rear setbacks grow as a wall gets taller. A wrong ground line can hide a setback breach as well as a height breach. The fix is simple: take levels from a current survey, record them across the site drawing, and repeat them on every elevation and section.
Setbacks that are missing or measured to the wrong point
Every wall, deck, pool edge and outbuilding needs a clear dimension to the boundary it faces. We often see setbacks shown for the main walls but not for a bay window, a raised alfresco or a carport post. The code also spells out which parts of a building may sit inside a setback, such as eaves within set limits, and which may not.
Lots on a corner, or behind another lot with a long access handle, follow different setback tables, so confirm the lot type early, before drawings are far advanced. A dimension taken to the wrong face of a wall can turn a compliant design into a failing one by a few hundred millimetres.
Area calculations that do not add up
The code caps gross floor area and requires a minimum amount of landscaped area, scaled to lot size. Both need a clear calculation on the plans, ideally with a shaded diagram showing exactly which areas were counted.
- Landscaped area: strips narrower than the minimum width set by the code do not count, and part of the total has to be in the front yard, with part in the rear yard.
- Gross floor area: some spaces, such as a single car space or certain storage areas, can be excluded. Others cannot. Show what was left out and why.
- Outbuildings: detached sheds, studios and garages have their own controls in the code, separate from the house, so include them in the calculations too.
Drawings that disagree with each other
A certifier reads the plans as one package. When the floor plan shows a window that is missing from the elevation, or a deck that is wider on the site plan than on the section, the certifier has to ask which version is right. Each question is a request for information, and each one adds time.
The BASIX certificate is a frequent source of conflict. It lists commitments such as window sizes, glazing types, insulation, rainwater tanks and hot water systems. If the design changes after the BASIX certificate was generated, the two no longer match and a fresh certificate is needed. Stormwater concept plans, cut and fill details and any retaining walls must agree with the architectural set too.
Site constraints nobody checked
Some problems sit outside the drawings altogether. Before lodging, confirm:
- the planning certificate for the land, which shows zoning, heritage status, bushfire and flood mapping, and whether complying development can be carried out there
- easements, restrictions and covenants on the title, since complying development does not override private covenants
- any sewer mains or other water authority assets near the work
- trees that need to be removed or pruned, which may need council approval first
- a bushfire attack level assessment where the site is bush fire prone land
If one of these rules the land out of the code, no amount of redrawing will help. Our CDC or DA: picking the approval your home project needs covers the other approval path.
Catching errors before you lodge
A plan assessment tests your drawings against the code before the application goes in, while changes are cheap. We flag missing information, conflicts between sheets and any standard the design does not meet, so your designer can fix them in one round. Once the plans are settled, request a quote, or read how our complying development certificate service runs.
Local help across NSW
CertifiBuild certifies Class 1 and Class 10 work in 39 council areas. Local rules on these council pages are a good place to start: Camden Council, Liverpool City Council, Inner West Council, Lithgow City Council, Strathfield Council, Hornsby Shire Council.
Suburb pages with local planning notes: Catherine Field, Edmondson Park, Greendale, Haberfield, Hartley, Homebush, Hornsby, Hurstville, Ingleburn, Jamberoo. You can also browse every service area.
Sources
- Housing Code, NSW Planning Portal
- Complying development, NSW Planning Portal
- Housing Code overview, NSW planning department