Front-line reports from two building commissioning projects
Often, buildings cost over $200 per square foot. That level of investment allows no slack in cost containment. The building infrastructure must run efficiently.
In each of the more than 100 buildings I have commissioned, results have exposed serious Mechanical, Electrical and Plumbing (MEP) system issues. These issues could have led to increases in equipment operating costs, additional repairs, and a degrading of Indoor Environmental Quality for building occupants.
Some issues indicated that equipment had not been programmed properly. In other cases, the equipment had been incorrectly installed, or not installed at all. Some buildings systems were operating less than optimally. I found equipment safeties certain to fail in an emergency.
MEP systems have substantial value. In a way, they are like the circulatory systems of the human body. Everything within the building works better when the MEP systems are optimized.
From the front-lines of building and renovation projects, I am always delighted when commissioning services minimize recurring costs while returning value. I have seen this happen more than 100 times.
Let’s explore a couple of examples.
Upgrading the upgrades 150 ways
In this commissioning project, a high school had recently upgraded air handling units. Large new rooftop units had been installed. The building automation system had been upgraded to monitor existing mechanical systems.
Ideally, commissioning should occur before construction is completed. Even greatest savings and efficiencies may be claimed when commissioning is done in the design phase.
That was not possible with this project. Upgrades had been substantially completed in late August, then were partially turned before the start of school. With classes already in session, full commissioning could not occur before the school winter break.
This late start in commissioning allowed many issues to pass through design and construction.
- I documented multiple heating/cooling coil water flow issues.
- Air and water balancing had either been incomplete or not properly conducted.
- The control system lacked capability of storing long-term trend data.
- Combustion air filters had not been installed on boilers. The burners in those boilers would have plugged and eventually stopped working.
- Equipment alarm functions had not been enabled and were not monitored on the building automation system.
- The demand control ventilation mode (CO2 control) on all new rooftop units was non-functional. This was due to improper start-up programming, control system programming, and sensor calibration of new rooftop units.
The facilities director had closely monitored this building, but only 43 systems passed inspection. Most issues were not visible. Comprehensive functional testing uncovered more than 150 issues.
A diligent commissioning agent goes beyond simply uncovering issues. Many can also be corrected as they are identified. Contractors must address the remainder.
Meeting specifications for a new building
Here’s another example where building commissioning brought immediate and ongoing benefits.
A 14 story, 264-unit apartment building was being planned. As always, the owners wanted to be sure that the completed building would meet specifications and operate efficiently.
The owners first contracted for commissioning in the Design and Submittal phases. Commissioning work continued during Construction and Turn-Over. This foresight and attention to detail paid off in at least 98 ways.
Like many projects at this scale, detailed requirements for some building elements were specified during Design and Submittal phases. This fine-tuning triggered changes in some MEP systems. Fortunately, the early stage commissioning avoided sacrificing quality or efficiency. Detailed reports showed owners that work was being done to timely specifications.
The Design and Submittal phase reports I prepared were based on technical drawings, equipment submittals, intended controls systems, and operational sequences. That way, I could provide comprehensive recommendations prior to installation and programming.
Early-phase commissioning work brought several project requirement variances to the owner’s attention. Energy efficiency would otherwise have been degraded. The issues had comfort and control implications as well.
Later, during construction, I did further inspections and inventoried equipment to confirm models and item counts. At project turn over I tested installed system components to ensure they functioned per the design and the owner’s intention.
At all stages, commissioning uncovered and documented variances from specifications and code issues. Equipment startup forms and “punch list” inspections alone would have left costly deficiencies.
- In violation of Energy Code, most exhaust fans lacked motorized dampers.
None of the specified backup electric heat strips had been installed within apartment fan-coil units.
- If a lead boiler were to fail, the backup boilers for heating and domestic hot water systems would not automatically engage. This would leave tenants “in the cold”!
- Variable speed make-up air units running at 100% speed failed to meet building pressurization requirements. Infiltration issues had been identified as a likely cause.
Air handling units for lobby and amenities areas struggled to meet space temperature requirements. Such inefficient operation would cause equipment wear and increased energy costs.
- Lighting motion sensors failed to automatically turn off hallway and community room lights. The installer had never tuned the sensors. Incorrect sensitivity level settings was causing false tripping. This eliminated any potential for energy savings.
- Nine systems of this apartment building passed inspection; 19 did not. 98 issues were documented so failed inspections and open issues could efficiently be resolved. The owner was not obliged to acknowledge full turn-over before completion to verified specifications.
Michael Kuk can be reached at his ecoPreserve email address, Michael@ecoPreserve.net.