The last few weeks of a mechanical project, when systems are tested, balanced, commissioned and handed over, are a small share of the programme but decide how the building performs for decades. When this phase is squeezed, the result is familiar: rooms that are too hot or too cold, alarms nobody understands and maintenance teams working without the information they need.
Commissioning starts at design
Commissioning is not an event at the end of construction. The owner's requirements, the basis of design and the commissioning plan should exist before installation begins, so every submittal and shop drawing can be checked against how the system is meant to operate.
Testing, adjusting and balancing done properly
TAB proves that air and water reach every terminal in the quantities the design intends. It depends on access to dampers and balancing valves, on test points installed in the right places and on a stable control system. Planning for these during installation avoids costly rework later.
Functional performance testing
Equipment that starts is not the same as a system that works. Functional tests run each sequence of operation: start-up, changeover, alarms, failure of a duty pump or chiller and recovery. They are where controls, mechanical and electrical works meet, and where most hidden problems are found.
A practical checklist
- Pressure and leakage tests completed and recorded before insulation and ceilings close
- Pre-functional checklists signed off for every piece of equipment
- TAB report reviewed against design flows, with deviations explained
- Sequences of operation tested end to end, including failure scenarios
- Integrated tests with fire alarm, smoke control and life-safety interfaces
- As-built drawings, O&M manuals and training delivered before handover
The payoff
A well-run final phase shortens the defects period, protects energy performance and gives the operator confidence from day one. For TERMA, testing and commissioning is part of how every project is delivered, not an extra at the end.