Is commissioning worth it? With paybacks of 12 to 18 months and sometimes less, I would answer a resounding "Yes!" However, in spite of commissioning and retro-commissioning proving their value time and again, the adoption of these practices is still slow. I believe the main causes for such hesitancy are lack of knowledge and misconceptions, which I hope to clear up to some extent in this article.
First, let's define commissioning. Sometimes in defining terms it is better to start with what it is not. Commissioning is NOT contractor start-up, testing & balancing (TAB), nor just a prerequisite for LEED. Commissioning is comprehensive testing of a building's systems to verify that the systems are independently and interdependently operating as specified or required by the owner. Commissioning (Cx) is performed on new construction or projects. Retro-Commissioning (RCx) is the commissioning of an existing building/system that has never been commissioned. Re-Commissioning is commissioning of an existing building/system that has already been commissioned. Typically, a building should be re-commissioned every 3 to 5 years.
In 2009, Dr. Evan Mills with Lawrence Berkeley National Laboratory released a report titled "Building Commissioning: A Golden Opportunity for Reducing Energy Costs and Greenhouse Gas Emissions". In the report, Dr. Mills stated that "Commissioning is arguably the single-most cost-effective strategy for reducing energy, costs, and greenhouse gas emissions in buildings today." In the study of more than 600 buildings, Dr. Mills found that the median energy savings for new construction and existing buildings was 13% and 16%, respectively; where the payback on energy savings alone was 4.2 years for new construction and 1.2 years for existing buildings. Additionally, the median non-energy benefits offset 49% of the commissioning costs, improving the payback period. In my experience, Cx on new construction generally pays for itself through misses caught by the Commissioning Agent (CxA) during a design review or site walk-through - the improved performance and efficiency of the facility and their associated savings are icing on the cake. As for RCx, I have generally seen energy savings of at least 15% to 20+% with paybacks of a year and a half or less. In September's Building Operating Management magazine, Microsoft stated they would "see energy savings of up to 20% each time" they re-commissioned a building. Sadly, neither of these studies tabulated the savings or revenues generated by commissioning due to increased building performance, occupant comfort, and worker productivity (such findings will be discussed in another FM360 article). However, based on energy savings alone, Cx and RCx should clearly earn themselves recognition and adoption into facility management programs and construction projects.
For new construction, a Commissioning Agent (CxA) should be brought on board by the Owner during the pre-design stage and stay as an intricate part of the team through at least the first year of operations. In doing such, the CxA can act as the bridge through the various project phases ensuring that the output, as realized during operations, aligns with the Owner's original project intent and expectations. As a key team member, the CxA can leverage their field experience to aid in design decisions and to identify costly misses during design review - it is much cheaper to change things on paper (or in CAD / BIM) than in concrete... Additionally, since the CxA is intimate with the systems and their respective sequence of operations, they are also a good resource for training facility staff and developing operating procedures.
For existing buildings, commissioning can be performed by in-house personnel; however, I would encourage you to hire an independent third-party CxA as they ทาวน์เฮ้าส์มือสอง will bring a fresh set of eyes and viewpoints. Additionally, a third-party CxA brings with them the expertise of best practices and recommendations that they have picked up in their commissioning of other facilities. The CxA should work with facility staff and occupants to identify problem areas and troublesome systems. The CxA should also discuss with the Owner the intent of the space and facility performance requirements; then they can develop Functional Performance Tests (FPTs) for each system. The CxA should provide a report detailing the issues they found, including those they resolved in the field, repair and maintenance items, and recommendations for capital replacement or performance enhancements. Depending on the firm, they may also be able to estimate the savings associated with their findings - just double-check their assumptions.
The key to any successful commissioning project is who you hire as the CxA. I cannot reiterate enough the importance of obtaining good, qualified commissioning personnel. I have been a part of great commissioning projects and have seen and heard of some deplorable ones - all of which depended entirely on the CxA. In selecting a CxA, I recommend qualifications-based because the quality of the firm hired will make all the difference in the success and value realized by the Owner. The CxA should be a full-time CxA, not an engineering or TAB firm that is trying to fill their schedule - I know that sounds harsh, but it happens all too often. You want someone that is not afraid to get dirty, because Cx is about the details. The CxA needs to understand various types of systems and be very familiar with controls systems, as controls is usually where most problems occur. They must be team players, not someone that just walks in to point out where people messed up - I have seen that railroad multiple projects. The CxA should act as a partner and should be seen as a partner by all parties.
There is much more to say about commissioning and retro-commissioning, but I will close for now. Please watch for other related articles, webinars, etc. at fm360consulting.com or feel free to contact me if you have any questions or would like further information. Additionally, I have posted Dr. Evan Mills report on our website, in case you want to dive further into the Lawrence Berkeley National Laboratory's findings.
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