This section provides an overview of commissioning: what it is, why it is done, how it is structured, what methods and procedures are used, and who does it today. Commissioning (Cx) is [generally] not common, yet it is becoming more frequent as building owners and others recognize that buildings and energy-using systems often do not perform as well in practice as designers predict. Although commissioning has many definitions, one simple one is "a set of procedures, responsibilities, and methods to advance a system from static installation to full working order in accordance with design intent." [Wilkinson, 1999] [Yoder and Kaplan, 1992].
Definitions vary according to the scope of commissioning and the activities related to it. Some commissioning projects begin early in the design stage and continue through ongoing operations and maintenance.
Commissioning of building systems has its roots in shipbuilding where the term was first used to describe the process to ensure a ship was seaworthy and ready for service. Commissioning is common today in industrial plant control systems. The principles behind commissioning are similar to those of "total quality management" (TQM). In TQM one attempts to establish criteria that can be tracked and evaluated to determine whether the quality of a desired activity or system meets expectations; for example, TQM practitioners might attempt to measure continuous improvements in employee productivity.
Some of the primary reasons that the buildings industry has begun to pursue commissioning are: first, building systems are more complex and dynamic than ever; Energy Management Control Systems, dynamic daylighting, direct-digital controls, variable frequency drives, and thermal-energy storage systems are just a few technologies that confuse building operators and need to be carefully tuned during installation. A second reason for commissioning is that demand-side management evaluations of energy-efficiency measures have shown that many measures do not perform as well as intended; a key reason is that the systems have not been commissioned properly [Piette et al., 1995]. Many building owners have a growing awareness of the need to track buildings' energy performance, and commissioning is seen as a way to establish proper operations during start-up. A third factor in the increased awareness of commissioning is that building designers, both architects and engineers, are less involved today than in the past in ensuring that a building they have designed actually works as intended. This lack of involvement results in a knowledge gap. The designers often do not understand how the systems they design actually function in practice. The focus on minimizing first costs, especially in speculative construction, means that little effort is placed on activities after a building's initial start up, so little attention is given to bringing building systems into operation with optimal energy efficiency, good indoor air quality, and realistic procedures for operation and maintenance.
Costs and Benefits of Commissioning
The Commissioning Process
The Scope of Commissioning
Who Should Commission a Building?
Commissioning (Cx) Team
Operations and Maintenance Hand-off