According to the National Institute of Building Science’s Whole Building Design Guide, one of the main benefits of implementing commissioning, or Cx as it’s known, is cost savings. In addition to offering a financial return on investment, Cx also results in reduced energy costs, fewer change orders, fewer contractor claims and call backs, a reduction in project delays, improved scheduling and better communication among the project team.
Commissioning can be implemented using many systems across a range of projects and during any stage of a facility’s life cycle. Here are a few of the different types of commissioning processes commonly used:
New Construction Commissioning
New construction Cx begins when a building is still in its idea stage. At this point in a building’s life cycle, whether a drawing or a schematic, it’s typically referred to as a “commissioning.” New construction commissioning is a systematic process involving the verification and documentation of a facility and its systems and assemblies, showing that they are planned, designed, installed, tested, operated and maintained to meet the owner’s project requirements (OPR).
Recommissioning, also known as ongoing Cx, is a process that is a repeat process for a previously commissioned project. This process takes into consideration advancements in performance and technology and how they change over time. Adopting this process makes it possible to restore the efficiency of a previously commissioned building and potentially further optimize it. With the rapid pace of technological change today, this kind of Cx is likely to continue to grow at an equally rapid pace.
As the name suggests, retro-commissioning involves testing and tuning a building after it has been built. As with other types of commissioning, this process ensures that a building’s systems are performing optimally for the current facility requirements. During this process, low-cost improvements like energy conservation measures or reliability enhancements are typically recommended so as to ensure optimal performance.
Monitoring-based commissioning, also known as MBCx, is a process that combines innovative commissioning techniques with new technology. Monitoring-based commissioning integrates energy management, utility and building automation data with analytical and diagnostic algorithms. These algorithms identify actual energy savings and performance enhancement opportunities in real time. MBCx seeks to resolve performance issues as they surface and continually refine facilities in order to ensure a building reaches its technical potential.
How Commissioning is Implemented
The Building Commissioning Association (BCA) publishes a series of best practices to aid the successful implementation of Cx. These tenets say that Cx is most effective when it begins in the predesign phase and recommend that a building owner assemble the commissioning team and begin to define the OPR at this stage. A commissioning team normally includes the owner, a commissioning authority, the design team, operations and maintenance (O&M) personnel, the construction team and a representative to speak on behalf of the occupants who will use the building once it’s complete.
The OPR communicate the owner’s expectations, goals and success criteria with measurable benchmarks to the rest of the team. These goals should be developed during the predesign phase with the input and guidance of the commissioning authority, O&M personnel and the building’s occupants. The commissioning authority defines the scope of commissioning for the project and helps incorporate this into the overall schedule and budget.
The Role of the Commissioning Authority
During the design phase, the commissioning uthority verifies that the building design is consistent with the OPR. The purpose of the commissioning authority is to communicate their requirements to the project team members, perform an independent review of the design documentation and facilitate cooperation among the project team. The commissioning authority is responsible for the creation of a plan to document the Cx process and for delivering this plan to the contractor. The plan includes the various roles and responsibilities of the individual team members, the systems commissioned, as well as the overall project schedule.
During the construction phase, the commissioning authority verifies that equipment and systems are properly installed and integrated per the design. This is achieved by carrying out site observations and witnessing system startups and third-party evaluations such as testing and balancing (TAB) and National Electrical Testing Association (NETA) testing.
As the building nears completion, the acceptance phase of commissioning begins. The authority works with the project team to complete functional performance testing, integrated systems testing and training in order to verify successful turnover. They then work alongside facility maintenance personnel to develop a commissioning manual for ongoing maintenance.
Finally, during the occupancy phase, the commissioning authority makes periodic trips to the project site to perform any deferred or seasonal testing. A review of the entire facility is conducted 10 months into the warranty period and a final commissioning record is developed.
What experience do you have with commissioning a project? Do you follow these steps? If you’ve been involved in the commissioning process, how did it compare to the guide outlined above? If you’re interested in more information on the commissioning process, we’ve written a white paper discussing this in greater detail that you might be interested in downloading — it’s linked at the bottom of this post. If my team and I can help you with your commissioning needs in any way, leave a comment here, send me an email at firstname.lastname@example.org or give me a call at 312-608-9826. I’d be happy to talk with you about the specifics of your project or needs.
Brian Lindstrom, PE, DCEP, is the national director of commissioning at Burns & McDonnell. He has been responsible for commissioning exceeding $8 billion and 19 million square feet of new construction, and retro-commissioning exceeding 10 million square feet of existing facility space.
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