Final services inspection for residential builds in Australia

What it is

The final services inspection is the closing hold point before the building surveyor issues an Occupation Certificate (NSW), Occupancy Permit (Victoria), Certificate of Final Inspection (Queensland) or Certificate of Occupancy (NT). Every service in the dwelling, power, water, drainage, gas, hot water, ventilation and smoke alarms, must be installed, commissioned and supported by a signed compliance certificate.

The building surveyor is not re-inspecting the electrical, gas or plumbing work itself. That is the licensed trade's responsibility. The surveyor checks that every required compliance certificate is on file, that the visible installation matches the plans, and that life-safety items pass a visual and functional test.

What the inspector checks

Electrical fit-off and AS 3000

Every electrical outlet, switch, light fitting, fan, oven, cooktop, exhaust fan and the main switchboard must be installed and tested. The licensed electrician issues a Certificate of Electrical Safety (Victoria, NSW), a Certificate of Compliance (Queensland) or state equivalent confirming the work meets AS/NZS 3000 Wiring Rules. The switchboard must be labelled with circuit identification.

Plumbing and AS 3500

Cold water, hot water, sanitary drainage, sanitary plumbing and stormwater must be tested and commissioned per AS/NZS 3500. The licensed plumber lodges a Compliance Certificate (Victoria), a Notice of Work and Certificate of Compliance (NSW) or Form 4 or Form 7 (Queensland).

Gas and AS 5601

Gas installations including cooktops, ovens, hot water units and bayonets must be installed under AS/NZS 5601.1. The licensed gas fitter performs pressure verification, leak testing and appliance commissioning, then issues a Gas Compliance Certificate. The inspector checks the certificate, the appliance data plates and ventilation for flued and unflued appliances.

Hot water

The hot water system is checked for commissioning records as well as tempering valve installation where required and the relief valve discharge point. Tempering valves to bathrooms and ensuites must deliver hot water at no more than 50 degrees Celsius under AS 3500.4.

Smoke alarms

Smoke alarms must comply with AS 3786 and be installed in every storey and in or adjacent to every bedroom, per Part 9 of the NCC Housing Provisions. Most states now require interconnected, hard-wired photoelectric smoke alarms in new builds. Queensland has elevated requirements under the Fire and Emergency Services Act. The inspector tests each alarm and the interconnection.

Final building items

The inspector also walks balustrade heights (1 metre minimum on stairs and balconies with vertical openings under 125 mm), door operation, window restrictors on upper levels, pool fencing if applicable plus BASIX or equivalent state energy efficiency commitments.

Common defects flagged on site

• Smoke alarms installed but not interconnected, or battery model where hard-wired is required.
• Missing Certificate of Electrical Safety from a sub-contractor licensee.
• Tempering valve not fitted to a bathroom hot water line.
• Gas Compliance Certificate scope does not cover an appliance installed late in the build.
• Switchboard not labelled with circuit identification.
• Relief valve drain discharging into a wall cavity.
• Smoke alarm too close to a bathroom door or ceiling fan.
• BASIX commitment item missing, like a heat-pump unit swapped for gas without an updated certificate.

A TradeLens scan picks up the documentary gaps: missing compliance certificates, expired trade licences, scope mismatches and unlogged smoke alarm model numbers.

Sign-off documentation

The Occupation Certificate pack must contain:

• Certificate of Electrical Safety covering the full scope of electrical work.
• Plumbing Compliance Certificate, Notice of Work and Notice of Completion or state equivalent.
• Gas Compliance Certificate covering every gas appliance and the gas line.
• Smoke alarm compliance statement with model numbers and install date.
• Termite management durability notice where applicable.
• Glass and glazing compliance certificate under AS 1288 where applicable.
• Insulation installer declaration matching the BASIX or NatHERS commitment.

State variations: NSW issues an Occupation Certificate under the EP&A Act with a BASIX completion check. Victoria issues an Occupancy Permit under the Building Act 1993 relying on Form Industry Compliance Certificates from each trade. Queensland issues a Certificate of Final Inspection under the Building Act 1975 with QBCC trade Form 16s. The home cannot be lawfully occupied until the inspector signs off and every trade certificate is filed.