Commissioning checks that a building actually works the way the owner needs it to, not just that equipment was installed. It covers systems like HVAC, controls, plumbing, electrical, fire alarm, life safety and building envelope. A commissioning agent (CxA), hired by the owner or sometimes the contractor, leads it.
The typical sequence:
- Owner’s project requirements and basis of design set what “working” means.
- Prefunctional checklists confirm equipment is installed correctly before startup.
- Startup by the installing contractor or manufacturer.
- Functional performance tests run each system through its operating modes (heating, cooling, failure, emergency power).
- Issues log tracks deficiencies to resolution.
- Training and documentation, including O&M manuals and systems manuals.
Hospitals, labs and data centers have heavy commissioning requirements. Energy codes and certification programs like LEED also require some level of it.
Why it matters
Commissioning is often on the critical path to substantial completion and occupancy. Failed tests on complex systems, or a controls contractor who isn’t ready, can delay turnover by weeks. On a project like a medical center, systems such as air pressure relationships and emergency power get scrutinized before the space can open.
Common mistakes
- Not scheduling commissioning time, so it gets squeezed at the end.
- Starting functional tests before systems are actually complete.
- Treating the issues log as separate from the punch list, so items fall through.
- Excluding commissioning support from subcontract scopes.
How os.construction handles it
We’re building closeout tools where commissioning issues, punch items and O&M documents tie to the same systems, locations and subcontracts. It’s in development.