The commissioning process is viewed as a necessary part of successful laboratory and vivarium projects today. No longer is it considered an extra expense compared to projects a decade ago.

Cutting costs by cutting back on the commissioning scope of work can mean extra costs in the long run.

The commissioning process is viewed as a necessary part of successful laboratory and vivarium projects today. No longer is it considered an extra expense compared to projects a decade ago. Yet, too frequently, the commissioning scope of work is reduced to a level that renders it less effective than required to properly prepare a facility for its intended use. This case study describes the effects of commissioning scope reductions on the operation and use of building systems.

A well-defined commissioning process should be included in every commissioning service proposal. On two recently completed projects, we (the commissioning agents) provided a detailed list of commissioning activities for each project phase. Both were laboratories with vivarium spaces and complicated mechanical, electrical, plumbing, and life safety systems integrated with the building automation system.
We reluctantly agreed to reduce our scope of work on each project to meet budget constraints and did our best throughout the projects to compensate for the exclusions. The items that had the most significant impact on the operation and use of the building were:

1. Replacement of Seasonal Testing with simulated tests off-season
2. Omission of Division 1 specifications from the commissioning agent’s review process
3. Exclusion of “unnecessary” systems from the commissioning process

The decisions met the project budget, but the truth of the actual costs to the owners was eventually revealed. There were no cost savings.

Replacement of Seasonal Testing with Simulated Tests Off-season
Most commissioning firms perform simulated tests of heating systems in summer and simulated tests of cooling systems in winter by using the opposite system to create false cooling and heating loads. It’s good commissioning practice to use this method to test sequences and alarms before systems are operated in their peak load conditions in season. The obvious downside of eliminating actual seasonal tests is that conditions such as cooling coil condensate capacity and freeze protection issues cannot be adequately checked by simple simulations.

That’s exactly what we discovered. A freezestat detects low temperatures near the water-filled coils to prevent freezing and bursting. We simulated a freeze condition in the summer during the acceptance phase testing. But when the coils were subjected to sub-zero conditions, freeze alarms switched off the air handling unit. Loss of airflow in the animal holding rooms quickly generated many more alarms since room environmental conditions were not maintained. Further investigation revealed insufficient water temperature and flow through the coil. If a technician had not been available to quickly diagnose and compensate for the condition at 3 a.m., the cost reduction decision could have ultimately cost the owner much more than the savings from commissioning scope reduction. Scheduled seasonal tests would have revealed that the fully operational heating system did not maintain water temperatures with enough stability to avoid the freeze condition.