Last month’s column introduced the rare but real possibility that a construction project may be so far behind schedule that not all systems can realistically be expected to be complete and operating when the owner needs to occupy the building. Most owners do not have the luxury of postponing their move-in date in order to wait for systems completion. If a project gets to that point (and we won’t even go into how that might happen), the main objective will be boiled down to whatever it takes to obtain a certificate of occupancy from the authority having jurisdiction (AHJ).
The AHJ will be focused primarily on life safety issues. Therefore, from a commissioning perspective, the top priority will be to concentrate on completion, start-up, and testing of fire alarm, fire protection, elevators, etc. However, how should the commissioning professional help the owner and project team prioritize the remaining systems? I believe it is necessary to take into consideration the relative difficulty, cost, and/or relative discomfort and disruption to the owner’s future operations of addressing things after move-in.
The following are some things to think about. The unique circumstances of each project will drive prioritization decisions.
Above-ceiling work. Any installation, wiring, insulation, etc., that will be concealed above ceilings, especially hard ceilings, should be completed before those ceilings are installed.
Accessible pipe and duct insulation. If the move-in date is during low-dewpoint weather conditions (i.e., winter for many of us and always in the desert), the exterior insulation on piping and ductwork could be postponed until after move-in. If the pipes and ducts are located in easily accessible mechanical rooms and shafts, the critical deadline for insulation is when ambient dewpoint temperatures rise into the 40°-50°F range. One exception to this would be steam piping and other high-temperature surfaces which present burn hazards if left uncovered.
Humidification. If the move-in date is during high-dewpoint weather conditions, the humidification system installation, startup, and testing could wait until dryer weather approaches.
Heating & cooling. If air conditioning (whether it is central chilled water or local DX) is only required during warm weather and the move-in date is during cold weather, completing the installation, start-up, controls, and testing of the cooling systems could be delayed. Similarly, if one or more of the heating systems are only needed during cold weather and the move-in date is during warm weather, completion of those heating systems could be postponed.
Lighting controls. As long as the lights function to illuminate the building’s interior and exterior, the energy conservation features of automatically controlling them on/off can wait.
Environmental control. As noted in last month’s column, there will likely be different priorities for indoor environmental control. Air handling systems serving mission critical spaces or high-profile public spaces need to be completed prior to move-in. Support spaces, or staff offices for which delayed comfort controls (within reason) will not make or break the owner’s operation, can be completed after move-in.
In addition to the life safety systems required by the AHJ, other systems which must function properly at move-in include ventilation of occupied spaces, domestic hot water, pressure control of mission critical spaces, and normal and emergency electrical power.
All of this must be clearly documented and understood by the building owner to ensure that the owner has reasonable end-of-construction expectations. Each deferred system completion should be accompanied by an explanation of the risk and future challenges inherent to the deferral. Of course, each outstanding item should also come with a realistic scheduled completion date after move-in. Such documentation should be helpful to everyone on the project team in order to assign resources to completing the highest priority items without being distracted by obvious deficiencies in other systems. ES
