Commissioning Beyond the Documents

Oct. 16, 2013
When you work out solutions, rather than merely document deficiencies, real commissioning value is realized—by all parties.

Building commissioning is a quality-based process, the fundamental purpose of which is to provide documented confirmation that building systems are planned, designed, installed, tested, operated, and maintained in accordance with the owner’s project requirements. Commissioning often is seen primarily as an added cost, which, admittedly, it is. This, however, should not overshadow the benefits commissioning can yield by lowering operational costs, increasing efficiency, reducing callbacks and occupant complaints, improving indoor-air quality and thermal comfort, and lessening the potential for premature equipment failure. Rather than an added cost, commissioning should be viewed as an investment. Studies by the U.S. General Services Administration, the U.S. Green Building Council (USGBC), ASHRAE, PECI, and the Building Commissioning Association indicate commissioning easily pays for itself over the life of a facility and, in many cases, within just a few years.

Over the last decade, commissioning has become an integral and accepted part of the design and construction process. It is becoming increasingly prevalent and, in some cases, even mandated. This can be attributed largely to the USGBC, which requires the incorporation of commissioning into facility design and construction for consideration and accreditation through its LEED, or Leadership in Energy & Environmental Design, program.

With commissioning becoming more common and new providers appearing every day, facility owners and operators are having an increasingly difficult time separating the wheat from the chaff. At the same time, commissioning providers are finding it harder to demonstrate the value they bring to the table.

In the commissioning industry, there has been a trend toward standardization, as a prescribed process using relatively uniform checklists, forms, and documentation procedures has developed over time. Unfortunately, there also seems to be a trend toward sole reliance on the basic recommendations of published commissioning guidelines and standardized reporting mechanisms. Anyone can understand and implement a prescribed process, but not everyone can see past the documents and associated requirements to carry out standard activities while maintaining focus on the quality of the end result.

Realizing the fundamental intent of commissioning requires an inherent understanding of a facility, the procedures/operations within, and the integration of building systems. This reaches far beyond documents and is where the value in commissioning is found.

For example, consider an enthalpy-control scenario for outside-air-economizer operation for air-handling systems serving a humidity-sensitive health-care facility. Pre-functional checklists were completed, and device installation and calibration and point-to-point communications were verified. Functional performance testing demonstrated effective sequence-of-operation programming and control logic. Also, automated control-system graphics were reviewed for applicability and representation of control points. The commissioning process was applied in accordance with the documents and standard industry practices. The result was a HVAC system applying accurate temperature and relative-humidity values to a tested enthalpy-controlled economizer sequence.

Had that been the end of the story, the system would have had no hope of operating according to the design intent. A technical understanding of enthalpy controls and the applied psychrometrics, together with an in-depth analysis of system operations—beyond what was identified and spelled out in the documents—revealed the equations embedded in the automated-control programming were calculating enthalpy incorrectly. This problem, which was relatively quick and painless to rectify, would have gone unnoticed through the “standard” commissioning process. As the result of a small investment in focus and quality, far-reaching seasonal operations and temperature-control problems that would have plagued the facility over time were avoided. Think about the money and labor that otherwise would have been spent investigating and troubleshooting the problem down the road.

Another suitable illustration is airflow validation. Typically, whether as part of contract documents or the commissioning process, demonstration of a certain percentage of airflow readings within prescribed tolerances is required. Normally, actual measured airflow must be within ±5 to 10 percent of specified design values.

Consider a room in which supply airflow is 5 percent below the design quantity, and exhaust airflow is 5 percent above the design quantity. This would pass a common document-driven commissioning process. Now, imagine there is no clear statement in the documents that a specific pressure relative to adjacent spaces must be maintained. This, however, is an operating room that must be positively pressurized for sterile conditions to be maintained. Understanding this requirement and the use of the space, could you walk away from the room with confidence the implied design intent was realized? What is the chance the room could exhibit a neutral or even negative pressure, and how important is that? Though not expressly required, validation of room-pressure relationships for critical areas as part of commissioning adds value.

As automated control systems become more sophisticated and tolerances and sensitivities for energy management tighten, verification beyond documents and control graphics is becoming increasingly important. All too often, information is taken at face value and not substantiated, justified, or proven through testing. Design professionals rely on computer load-calculation programs and vendor-provided equipment-capacity selections. Controls vendors install factory-calibrated devices and implement canned control-sequence programming. Device values, component positions, and equipment statuses reported on computer screens commonly are accepted without a second thought.

Project documents often include general requirements for system operating sequences and control strategies, leaving equipment/system providers and controls vendors to determine the details. While operating parameters and setpoints often are spelled out in documents, the processes by which requirements are satisfied routinely are undefined and, thus, left open to interpretation. Examples include system interaction and interlocks, interfaces between packaged controls and building-automation systems (BAS), control sequences and capacity-staging requirements for packaged equipment, and modes of operation, such as startup, shutdown, normal, and emergency. Commissioning providers have the advantages of objective involvement and experience to draw attention to voids in project documents.

Calling attention to such details as part of a commissioning design or submittal review early in a project can drive action and head off potential delays and expenses. Having manufacturers, equipment vendors, and design professionals confirm details, capabilities, and compatibilities of packaged and central control systems prior to or at least during the selection process is extremely beneficial, although it may not be expressly required in documents. How many times have you encountered a scenario in which an aspect or feature of equipment control cannot be implemented or must be manipulated because of incompatible packaged controls or because a specific piece of equipment is required to satisfy an owner’s needs? Perhaps the owner invested a significant amount of time and money into a sophisticated BAS, which is able to inform the owner only of on/off status and general alarm condition for specialized equipment because the BAS is not compatible with the packaged control system. Would the recommendation of a controls gateway or added device enabling a full controls interface be considered beneficial by the owner? How about the ability to seamlessly view and integrate the control functions of all equipment and components for the life of the facility?

While it is common for system sequences to be outlined in great detail in project documents, it also is common to see, “On the reverse, the opposite shall occur,” or something similar. This clouds the intent and, when commissioning is performed strictly to the requirements of documents, may not yield all of the desired results. Requesting clarification and details serves not only to spell out testing requirements, it sheds light on criteria that may not have been considered by the design and operations team. For instance, is the manual, or “hand,” mode of system operation required to be the same as the fully automatic mode? What about bypass operation of variable-frequency drives? For critical systems and applications, when and how do system-control safeties come into play? Should a temperature-control safety device de-energize an air-handling system serving a critical health-care or laboratory facility? Clarification and understanding of unstated or otherwise implied expectations can be valuable to an entire team.


With project schedules continuously being compressed, there is a trend toward simplification and streamlining of design and construction processes and documentation. At the same time, building systems are becoming increasingly complex, and the bar for performance is being raised. Bridging this gap is where commissioning providers can bring the most value to clients. If you commission beyond the documents, the question of whether commissioning services are worth the investment is easily answered.

Whether you are a facility owner/operator trying to distinguish between quality- and commodity-based commissioning providers or a commissioning provider looking to increase the value you bring to a project, look for opportunities for commissioning beyond the documents. More often than not, “hidden” and overlooked items are the most valuable and rewarding, no matter your role. These items serve to “connect the dots,” streamline the process, and maintain overall quality.

When you work out solutions, rather than merely document deficiencies, real commissioning value is realized—by all parties. It is the quality of the end result that matters most and remains with us for a long time to come.

James I. Givens, CxA, EMP, has been providing commissioning services through RMF Engineering Inc.’s Field Services division for more than 15 years. He serves on the board of the National Capital Chapter of the Building Commissioning Association. He can be reached at [email protected].

Did you find this article useful? Send comments and suggestions to Executive Editor Scott Arnold at [email protected].