About Mandatory Critical Stage Inspections

When carrying out Building Works in NSW under a Development Application or Complying Development approval pathway, legislation requires inspections to be carried out on the Principal Certificate at ‘critical stages’ of construction.

These inspections are to verify that the works at that stage are compliant with the Building Code of Australia (BCA), relevant Australian Standards and Development consent conditions, including consistency with Approved Plans.

What Critical Stage Inspections are required for my project?

Critical stage inspections required vary by Building Classification.  As part of the Principal Certifiers role, they will nominate the required inspections specific to each project on the Approval documentation. The below is required at minimum.

Includes Dwellings, Secondary Dwellings, Dual Occupancies (Side by side), Multi-Res Terraces, Sheds, Pools, Retaining Walls, Carports, and other ancillary residential development.

  • Piers/Footings – after excavation and before placement of concrete
  • Slabs or other reinforced concrete elements – before placement of concrete
  • Framing – before covering (or insulation) installation of any floor, wall or roof framing
  • Waterproofing – before covering of the waterproofing membrane
  • Stormwater – before covering drainage connections
  • Completion – after the work is completed

Note: Where a Swimming Pool is installed, a barrier inspection is to be booked ‘as soon as practical’ after being erected

Includes Apartment Buildings, Group Homes, Boarding Houses, and buildings for children, the elderly and people with a disability.

  • Piers/Footings – after excavation and before placement of concrete
  • Fire service penetrations – at least 1 of each type of protection method on each storey
  • Fire-resisting junctions – prior to covering of internal fire-resisting construction bounding a sole occupancy unit (SOU). At least 30% of SOU’s must be inspected on each storey
  • Waterproofing – before covering of the waterproofing membrane
  • Stormwater – before covering drainage connections
  • Completion – after the work is completed

Includes Office buildings, Retail Shops, Restaurants, Cafes, Hairdressers, Warehouses, Carparks, Factories, Hospitals, Schools, Childcare centres and buildings where people gather or assemble.

  • Piers/Footings – after excavation and before placement of concrete
  • Fire service penetrations (Class 9a or 9c only) – at least 1 of each type of protection method, on each storey
  • Stormwater – before covering drainage connections
  • Completion – after the work is completed
A mandatory critical stage building inspection being performed on a shed by a Buildcert Certifier
Buildcert Registered Certifier Performing a mandatory slab inspection

Booking Mandatory Critical Stage Inspections

The Principal Contractor (Builder) or Owner-builder is responsible for booking all required inspections and ensuring that the inspection has been deemed Satisfactory before continuing with work.

Buildcert make it easy to book Inspections, this can be done via our online booking form, emailing inspect@buildcert.com.au or calling our friendly office team on 1300 457 400.

If you book before 3 pm on a business day, we can complete the inspection the following day.

What happens during a Critical Stage Inspection?

Our Certifiers carry out a physical inspection of the works on site to confirm compliance with Approved Plans, Approval documentation (For example, Structural Engineering Plans), National Construction Code and the applicable Australian Standards at that point in time.

The result of the Inspection is issued by an Inspection Notice via email, deeming the works either ‘Satisfactory’ or ‘Unsatisfactory’.

The Inspection Notice will reference any items to deem the works ‘Satisfactory’. This may require documentation to demonstrate that the works are compliant – including surveys, engineering certificates, waterproofing certificates, installation statements or various other compliance certificates from consultants or trades. The anticipated list of documentation required during the project is listed on the Approval documentation and will be referenced throughout the project.

Certifiers are also required to verify site controls and overall consent compliance at each inspection – this includes items such as site fencing, signage, erosion control and/or connection of downpipes.

Mandatory Critical Stage Inspections
Buildcert Registered Certifier providing a final inspection

Missed Inspections

NSW Legislation does not permit an Occupation Certificate where a critical stage inspection was not booked or carried out, unless the circumstance is deemed ‘unavoidable’ and satisfactory evidence is provided demonstrating that the works are compliant.

NSW Fair Trading has advised that the acceptable circumstances to be deemed ‘unavoidable’ is a “high bar”, with reasons such as not being aware of the inspection requirements or miscommunication (or similar) generally not being a valid reason.

If an inspection is missed, the Owner is required to be formally notified, and a statutory declaration is to be completed detailing the circumstances, and satisfactory evidence of completion of works (for example, Engineering Certification and photos) is provided for review to determine if an Occupation Certificate may still be issued.

From 2018 all Certifiers are required to report data on Building Certification to the NSW Government. This includes daily reporting of inspections carried out, with the type of inspection, result and builder/owner-builders details shared. This results in a high level of transparency to NSW Government organisations across all projects and builders, including unsatisfactory and missed inspections.

Have any questions? Call the Buildcert team now on

Swimming Pool & Spa Association
Association of Accredited Certifiers
Housing Industry Association
Master Builders Association New South Wales
The Urban Development Institute of Australia
Mandatory Critical Stage Inspections