Commissioning and Handover Requirements for Building Services

What You Need to Know

Commissioning is how you prove a building works. It covers every system - HVAC, electrical, fire, hydraulics, and controls. Without it, you get complaints, wasted energy, and failed certifications. AIRAH DA27 and the CIBSE Commissioning Codes set the rules in Australia. Green Star now accepts both. Get commissioning wrong, and the building does not get handed over.

• All building services must be commissioned before handover to the owner. AIRAH DA27 defines the process for HVAC&R systems. CIBSE Code M (2022) covers management of the full commissioning process across all disciplines. (AIRAH DA27; CIBSE CCM)
• SA TS 5342:2021 is Australia's first building commissioning technical specification. It fills the gaps between discipline-specific standards and gives a whole-of-building framework covering HVAC&R, electrical, fire protection, hydraulics, automated building elements, and smart building IT systems. (Standards Australia)
• Air systems must be tested, adjusted, and balanced (TAB) to within plus or minus 10% of design airflow at each outlet. Hydronic systems must be balanced to within 10% of design flow at each terminal device. (CIBSE Code A; CIBSE Code W)
• All TAB instruments must be calibrated within 12 months of use. A written balance report is required for every system. (Industry standard practice)
• The BMS must be commissioned and verified before TAB work starts. Control sequences must match the design intent document. (AIRAH DA27; CIBSE Code C)
• Green Star Design & As Built (Man-2) requires commissioning in line with CIBSE Commissioning Codes or both AIRAH DA27 and DA28 used together. (GBCA Green Star)
• CIBSE Code M requires seasonal commissioning - testing during both heating and cooling seasons - for up to 12 months after handover. (CIBSE CCM, Stage 7)
• All defects must be classified: Type-A (critical, must fix before proceeding), Type-B (must fix before handover), Type-C (minor, fix after handover by agreement). (SA TS 5342; AIRAH DA27)

Take a 5,000 m² commercial office with HVAC, fire detection, emergency lighting, and a BMS. Commissioning starts long before anyone turns on a fan.

During design, the engineer writes the commissioning specification. This document lists every test, every tolerance, and every piece of evidence the commissioning agent will need. For the HVAC system alone, that means airflow measurements at every diffuser, water flow at every fan coil unit, and control sequence verification at every AHU.

During construction, the contractor runs pre-commissioning checks. Are the ductwork joints sealed? Are the pipe supports at the right spacing? Are the electrical connections tight? These checks happen system by system, recorded on inspection test plans (ITPs).

Once a system passes pre-commissioning, the commissioning agent runs functional performance tests. The AHU starts up. Airflow hits each diffuser. The BMS logs temperatures, pressures, and damper positions. If the supply air to Zone 3 reads 15% below design, the balancing contractor adjusts dampers until it falls within the 10% tolerance.

After all systems pass individually, integrated systems testing begins. The fire alarm triggers. The smoke dampers close. The emergency lighting switches on. The lifts return to ground. If any one link fails, the whole chain gets retested after the fix.

Handover happens in stages. The contractor provides O&M manuals, as-built drawings, and a full set of commissioning certificates. Facilities staff attend training - both classroom sessions and hands-on walkthroughs. The Provisional Acceptance Certificate (PAC) is issued after a successful trial period. The Final Acceptance Certificate (FAC) comes after the performance guarantee period, which typically runs 12 months.