Building commissioning (Cx) is an all inclusive systematic quality assurance process of ensuring that building systems are designed, installed, tested, and capable of being operated and maintained to perform interactively according to the design intent and the owner’s operational needs. Thus, the U.S. General Services Administration (GSA) defines commissioning as: “A systematic process of assuring by verification and documentation from the design phase to a minimum of one year after construction that all facility systems perform interactively in accordance with the design documentation and intent, and in accordance with the owner’s operational needs, including preparation of operation personnel.” For new construction the process ideally begins at a project’s inception (i.e., the beginning of the design process) and continues through construction, start-up, inspection, testing, balancing, acceptance, training, and an agreed warranty period (i.e., occupancy and operations). Building commissioning (Cx) therefore encompasses all the necessary planning, delivery, verification, and managing risks to critical functions performed in, or by, facilities. Cx also accomplishes higher energy efficiency, improved environmental health and occupant safety, and improved indoor air quality (IAQ) by making sure the building components are working correctly and that the plans are implemented with the greatest efficiency. It basically confirms that the systems are efficient and cost effective, and the installation is adequately documented according to requirements written into the project contract documents and that the operators are adequately trained.

Most research clearly shows that the vast majority of building energy systems fail to function to their full potential. Irrespective of how carefully a building is designed, if the systems, equipment, and materials are not installed and operating as intended, the building will not perform well. Poor communication of design intent, inadequate equipment capacity, inferior equipment installation, insufficient maintenance, and improper system operation all adversely impact energy cost savings. And perhaps now more than ever, effective operations require subsystems and components that work effectively and reliably and a building staff that has the knowledge and resources to operate and maintain them. This is sometimes difficult in today’s competitive construction environment where building owners and project team members have become increasingly cost conscious and seldom allocate for an adequate budget to quality assurance processes. The nature of deficiencies frequently found in noncommissioned energy projects vary considerably and include:

As previously mentioned, often during the commissioning process, it is discovered that systems do not meet performance requirements due to errors in the design. Also, if a member of the design team is the designated “commissioning authority (CxA),” there is an obvious conflict of interest, because a person representing the design team may compromise the commissioning process to justify the design. This is why it is so important to employ complete commissioning of the project. According to LEED, the intent of fundamental commissioning is “To verify that the project’s energy-related systems are installed, and calibrated to perform according to the owner’s project requirements, basis of design and CDs.

A study prepared in October 2003 for a group of more than 40 California government agencies concluded that investing in green construction will pay for itself 10 times over. The study, conducted by the Capital E Group at Lawrence Berkeley National Laboratory with input from a number of state agencies, reflects the most definitive cost-benefit analysis of green building to date.

Commissioning costs will vary with each project and depends on several factors such as the project’s size, complexity, and the scope of the commissioning process. For this reason, commissioning costs are difficult to accurately estimate. However according to INVIRO Design & Consulting, LLC, “The total building commissioning costs for commissioning agent services can range from 0.5% to 1.5% of total construction costs (according to U.S. Department of Energy’s Rebuild America Program, written by the Portland Energy Conservation, Inc. (PECI)). The National Association of State Facilities Administrators (NASFA) recommends budgeting 1.25 to 2.25% of the total construction costs for total building commissioning agent services. GSA’s commissioning practice is expected to cost approximately 0.5% of the construction budget for federal buildings and border stations. More complex projects such as courthouses could run 0.8–1% of the construction budget and even more complex facilities such as laboratories can exceed 1%. Median commissioning costs were found to be $0.30/ft2 for existing buildings and $1.16/ft2 for new construction by the Lawrence Berkeley National Labs. iii Factors influencing commissioning costs include facility type, phasing 24/7 operations, the depth and breadth of commissioning services, the level of commissioning desired, and the systems and assemblies chosen to be commissioned (source: INVIRO Design & Consulting, LLC).” But it should be noted that there is no standard convention for determining which costs are included in the total cost of commissioning. Because it is difficult to define precisely, the cost of commissioning, it is most often presented as a range of potential costs rather than a specific dollar amount. But no matter how it is defined, the cost of commissioning generally accounts for only a very small percentage of the overall construction budget and an even smaller percentage of the building’s life cycle costs.

The potential for long-term cost savings from building commissioning is considerable, and which theoretically, could induce owners to perform system commissioning with payback being a major consideration. It is not surprising, however, that studies show that commissioning costs per square foot tend to be higher for more complex buildings such as hospitals, and as a result of their relatively high energy intensity, commissioning payback has also been found to be lowest in these building types. For existing buildings, the median whole-building energy cost savings associated with commissioning was found to be about 15%. Some of the potential long-range cost benefits of conducting an effective commissioning process are outlined below:

As previously mentioned, commissioning serves as a general record of the owner’s expectations for project performance during the project delivery process. It is a conscience team effort that documents the continuity of the project as it progresses from one project phase to the next. In the earliest phases of the project, i.e., Planning and Development, we see the establishment of planning and programming documents that begin to define an owner’s requirements, goals, and standards for building performance. By appropriately documenting the entire project delivery process, a chronological perspective is put into place that outlines and clarifies the iterative process of determining the agreed-to project requirements at each phase of the development process. Commissioning documentation therefore becomes the road map for the success criteria to be met by facilities when they are put in service and verifies that designed and installed systems meet the specified standards. After the building project is occupied, commissioning documentation becomes the benchmark to ensure that the building can be maintained, retuned, or renovated to meet future needs. The OPRs are documented from the beginning of the facility’s initiation, recording compliance, acceptance, and operations throughout the facility’s life cycle. These include:

The CxA shall organize and lead the commissioning team and essentially guide the Commissioning Process for all commissioned systems. In the preconstruction phase, this will include peer review of design submittals, ensuring that the owner’s expectations are adequately documented in the Owner’s Project Requirements, produce systems manual, and reviewing all contractor submittals. For example:

According to the Building Commissioning Guidelines by Energy Design Resources, “Commissioning is a team process in which members of the project team each play defined roles. The commissioning team often includes the building owner or project manager, commissioning provider, design professionals, general contractor, subcontractors and manufacturer’s representatives. For LEED projects, the LEED coordinator should also be a member of the commissioning team.” Furthermore, “The team may also include facility staff, testing specialists or utility representatives. It is important to remember that the commissioning team does not manage the design and construction of the project. It merely promotes communication among team members to identify and resolve issues in a collegial and systematic fashion.”

Although the building industry remains at times divided on which party should be the CxA, it is strongly recommended that an independent party be the CxA, i.e., neither the contractor, A/E nor the CM. CxA should be motivated solely by the needs of the owner and the facility user and should not normally be competitors of the A/E or contractors. Individuals chosen should be highly specialized in the types of facilities and systems to be commissioned (LEED, for example, has specific requirements in this respect), and the more complex the project, the more experience is required of the CxA. Selecting a CxA with directly relevant experience is of particular importance when dealing with projects with special or mission-critical needs such as hospitals or labs. Because of the level of technical oversight that is expected, individuals should be a Certified Commissioning Professional (CCP), licensed Professional Engineer, or have applicable experience in specialized systems/facilities being installed, in addition to extensive experience in the design, optimization, remediation, and acceptance testing of applicable systems as well as building manual preparation and training.

The following is from Section 01 91 00—General Commissioning Requirements. It is Guidance for designers and specifiers, with suggested language to be modified and incorporated into project specifications and provides a brief overview of the typical commissioning tasks during construction and the general order in which they occur (source: BuildingGreen, Inc. 2007):

The LEED intent of fundamental commissioning “is to verify that the building’s energy-related systems are installed, calibrated, and perform according to the owner’s project requirements, basis of design and construction documents.” Fundamental commissioning is a prerequisite for LEED certification (unlike Enhanced Commissioning which is a credit and not a prerequisite) and is required for both new construction and major retrofits, as well as for medium or large energy management control systems that incorporate in excess of 50 control points. Moreover, commissioning is especially important when large or very complex mechanical or electrical systems are in place or where on-site renewable energy generation systems, such as solar hot water heaters or photovoltaic arrays are in place. Commissioning should also be considered when innovative water-conservation strategies, such as composting toilets or gray water irrigation systems, are installed.

For a LEED credit (2 points), enhanced commissioning is required in addition to the Fundamental Commissioning prerequisite. The intent of enhanced commissioning according to LEED is “To begin the commissioning process early in the design process and execute additional activities after systems performance verification is completed.” For the Commercial Interiors category, for example, the intent is to verify and ensure that the tenant space is designed, constructed, and calibrated to operate as intended. This requires the implementation, or to have a contract in place requiring implementation, further commissioning process activities in addition to the Fundamental Commissioning prerequisite requirements as stated in the relevant LEED Reference Guide (e.g., the Green Building Design and Construction, 2009 Edition).

Although building commissioning has become a critically important aspect of new construction projects and is used primarily to ensure that all installed systems perform as intended, the reality is that most existing buildings have never encountered the commissioning or quality assurance process and not unexpectedly have been found to be performing well below their intended design potential. Retrocommissioning can address problems that occurred during design or construction or address problems that may have developed throughout the building’s life. The Lawrence Berkeley National Laboratory (LBNL) conducted a recent study of 60 different types of buildings which confirms this inefficiency and shows that:

Upon completion and turnover, the building goes into the hands of the owner and operators. But although the project may be considered to be complete, some commissioning tasks from the initial commissioning contract continue throughout the typical 1-year warranty period.