Building Certification Glossary: NSW Terms Explained

Building certification in NSW comes with its own vocabulary. If you’re building, renovating, or just trying to understand a quote from a certifier, this glossary covers the key terms you’ll encounter. Everything is explained in plain English, with links to more detailed guides where relevant.

Certificates and approvals

Complying Development Certificate (CDC)

A fast-tracked building approval that combines planning permission and construction approval into a single certificate. Available for projects that meet specific standards under the SEPP (Exempt and Complying Development Codes) 2008. A certifier must determine a CDC application within 10 days of receiving all required documentation. See our full guide: What is a CDC in NSW?

Construction Certificate (CC)

A certificate confirming that detailed construction plans comply with the National Construction Code (NCC) and any conditions of development consent. Required before building work can start after a Development Application has been approved. Can be issued by a private accredited certifier or council.

Occupation Certificate (OC)

The final certificate issued after building work is complete, confirming the building is safe, compliant, and suitable for occupation. Required before a building can be legally occupied. Issued by the Principal Certifier after the final critical stage inspection.

Development Application (DA)

A formal application to your local council for planning approval. Required when a project doesn’t qualify for exempt or complying development. Council assesses the DA against local planning controls, zoning, and environmental considerations. If approved, a Construction Certificate is then needed before building work starts. See: CDC vs DA: which pathway?

Exempt development

Minor, low-impact building work that doesn’t require any formal approval. Includes things like small garden sheds, low fences, and minor internal renovations with no structural changes. The criteria are set out in the relevant SEPP and your local council’s planning controls.

BCA report

A Building Code of Australia compliance report that assesses a building’s design against the requirements of the NCC. Often required as part of a DA or CC application, particularly for commercial buildings or complex residential projects. See: PROCERT BCA reports

People and roles

Principal Certifier (PC)

The person or body appointed to oversee compliance during construction. The PC conducts mandatory critical stage inspections and issues the Occupation Certificate. Must be appointed before building work begins, regardless of whether the project was approved via a CDC or DA + CC. The appointment is the property owner’s decision, not the builder’s. Previously known as the Principal Certifying Authority (PCA). See: What does a building certifier do?

Building certifier (accredited certifier)

A qualified professional registered under the Building and Development Certifiers Act 2018 to assess building work for compliance and issue certificates. Can issue CDCs, CCs, and OCs, and can be appointed as Principal Certifier. Subject to audit by Building Commission NSW.

Building Commission NSW (BCNSW)

The NSW Government agency that regulates the building industry, including certifiers. Formed in December 2023 by merging the Office of the Building Commissioner and parts of NSW Fair Trading. Conducts audits, investigates complaints, and enforces compliance.

Legislation and codes

Environmental Planning and Assessment Act 1979 (EP&A Act)

The primary planning and development legislation in NSW. Governs development applications, CDCs, construction certificates, occupation certificates, and the appointment of Principal Certifiers. The foundational law for all building approvals in NSW.

EP&A (Development Certification and Fire Safety) Regulation 2021

The regulation under the EP&A Act that contains detailed procedural requirements for certification, including the six mandatory critical stage inspections (Section 61) and documentation requirements.

Building and Development Certifiers Act 2018 (BD&C Act)

Governs the registration and regulation of building certifiers in NSW. Gives the Secretary audit powers and sets out penalties for non-compliance (up to $110,000 for companies and $22,000 for individuals for obstructing audits).

Home Building Act 1989

Governs licensing of builders and tradespeople, statutory warranties (6 years for major defects, 2 years for other defects), and home building compensation insurance. The consumer protection backbone for residential building work in NSW.

National Construction Code (NCC)

Australia’s primary code for the design and construction of buildings. The Building Code of Australia (BCA) forms Volumes 1 and 2 of the NCC. All building work in NSW must comply with the NCC.

State Environmental Planning Policy (SEPP)

State-level planning instruments that set standards for specific types of development. The most relevant for building certification is the SEPP (Exempt and Complying Development Codes) 2008, which defines what qualifies as exempt or complying development.

BASIX (Building Sustainability Index)

A mandatory sustainability assessment for most residential development in NSW. Evaluates water efficiency, thermal comfort, and energy usage. A BASIX certificate must be obtained before lodging a CDC or DA application.

Insurance and consumer protection

Home Building Compensation Fund (HBCF)

A last-resort insurance fund that covers homeowners when a builder cannot complete work or rectify defects due to insolvency, death, or disappearance. Required for residential building work valued at over $20,000 including GST. Maximum payout is $340,000 per dwelling. Administered by SIRA.

Statutory warranties

Warranties that apply automatically to residential building work under the Home Building Act 1989. Cover major defects for 6 years and all other defects for 2 years from completion. A major defect includes defective design, workmanship, or materials in load-bearing components, waterproofing, or fire safety systems.

Inspections and compliance

Critical stage inspections

The six mandatory inspections required for Class 1 and 10 buildings in NSW, conducted by the Principal Certifier at specific points during construction. Set out in the EP&A Regulation 2021, Section 61. See: The 6 mandatory building inspections in NSW

Class 1 building

A classification under the NCC for a single dwelling, being a detached house, or one of a group of attached dwellings (such as a terrace house or townhouse). Most residential homes in NSW are Class 1 buildings.

Class 10 building

A classification under the NCC for non-habitable structures associated with a dwelling, such as garages, carports, sheds, fences, retaining walls, and swimming pools.

Reactive soil

Soil that expands when wet and shrinks when dry, causing ground movement that can affect building foundations. Common in parts of Western Sydney and other NSW growth areas. A geotechnical (soil) report is required to classify the soil and ensure the foundation design is appropriate for the site conditions. See: Why soil testing matters

Planning and lodgement

NSW Planning Portal

The online platform used for lodging certification applications (CDCs, CCs, OCs, PC appointments) and DAs in NSW. The portal charges a $47 lodgement fee per application. Certifiers must report certification data via the portal from 1 July 2025.

Floor Space Ratio (FSR)

The ratio of a building’s total floor area to the area of the land on which it sits. Used in planning controls to limit the size of buildings. Exceeding the allowable FSR may disqualify a project from the CDC pathway.

Setback

The minimum distance a building must be from a property boundary. Different setback requirements apply to front, side, and rear boundaries. Setback requirements are specified in the relevant SEPP or council’s planning controls and are a key criterion for CDC eligibility.

Frequently asked questions

What does CDC stand for in building?

Complying Development Certificate. A fast-tracked approval combining planning and construction approval into one certificate for eligible projects in NSW.

What is the difference between a CC and a CDC?

A CC only covers construction compliance and requires a separate DA for planning approval. A CDC combines both into one certificate, making it faster and simpler for eligible projects.

What does a Principal Certifier do?

Oversees compliance during construction, conducts the six mandatory inspections, and issues the Occupation Certificate. Must be appointed before building work begins.

What is an Occupation Certificate?

The final certificate confirming a completed building is safe and suitable for occupation. Required before a building can be legally used.

What is BASIX in NSW building?

Building Sustainability Index. A mandatory sustainability assessment for most residential development in NSW, covering water, thermal comfort, and energy performance.