Why do data centres take so long to commission?
Everyone wants the programme shorter. In mission-critical buildings, that is exactly where you should not cut.
If you have spent time in construction, you know the scene. It is the end of the project, it is running late, goodwill and fee are running out, and everyone — client, project manager, contractor — just wants to finish. So the MEP engineers get asked the same question: do you really need those weeks to commission this thing? Can it be done in one or two fewer? Get squeezed, rush the commissioning, and you spend the next six months after handover coming back to fix what was not tested properly.
Mission-critical is different
In data centres the "critical" in mission-critical is the giveaway. These facilities have to work when they are needed — especially in a failure or maintenance scenario, which is the whole reason for the redundant systems. To get that assurance, we commission in structured levels rather than one rushed push:
Level 0 — Design and planning. Collate the design and construction information that sets out how the facility should be built and operated.
Level 1 — Factory testing. Test equipment where it is manufactured, to confirm it does what it says on the label before it ships.
Level 2 — Component installation. Once delivered and installed, verify it is the right equipment in the right place, with preliminary checks before it is energised.
Level 3 — System start-up. Energise the equipment and confirm everything runs the right way.
Level 4 — Functional testing. Test individual systems — HVAC, fire, electrical, BMS — in both normal and failure conditions.
Level 5 — Integrated systems testing. Turn the data centre "on": simulate a real load in the data hall (banks of heaters) and prove every system works together, including under failure.
Level 6 — Close-out and handover. Complete the commissioning documentation and O&M manuals, and train the operations staff.
That rigour — proving the building works before anyone relies on it — is why commissioning takes the time it does, and why cutting it is a false economy.