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Retro-Commissioning: What is it?

As I said in my last post, I love my job: it is solving complex problems that help buildings run more efficiently and leaves Owners, Facilities Managers, and Occupants with fewer headaches related to their mechanical systems. Retro-commissioning (RCx) is a system-wide approach that lets us see how all the building components come together to work best – and if they are NOT working, RCx figures out why, and how to fix it. But what exactly does that process look like?

Retro-commissioning shares many features of New Building Commissioning (takes place before and during new construction) and Re-commissioning (takes place in a facility that has previously gone through a commissioning process and typically takes place 3-5 years after original construction/commissioning). All these services take a high-level view of the facility, including investigating design, installation, and control of mechanical systems, especially how the various systems interact with each other. From this bird’s-eye view, we drill down into the details of each system: every mechanical component, sensor, sequences of controls, etc. This holistic and systematic process is how we catch items that will cause problems, or already are!

RCx is simply the commissioning process applied to an existing building where a commissioning effort has never taken place. Often, we are called in to trouble-shoot an individual problem with the mechanical system(s); however, RCx is a highly adaptable process and we tailor our services to the needs of each client: RCx can consist of going through an entire building’s mechanical system or a single piece of equipment. In upcoming posts, I will further outline why I believe RCx should be THE starting point, not only when you have a specific mechanical problem, but if you have any thoughts of equipment upgrade or replacement, remodels, or are concerned about your on-going utility costs. I will also describe the differences you may run into among RCx providers, and why I believe our on-site approach at CCx delivers the most powerful results. But first, let me describe the general RCx process:

The Process

The meat and potatoes of a Retro-Commissioning Process comes down to four phases. Some say it is five phases; some say its six. Additionally, not everyone in the industry uses the same terminology, but since I am writing this post, I am going to use our process terminology.

It is also worth noting that an RCx project is not frequently a linear process. Sometimes we discover problems in one area that requires us to revisit work previously completed and restart or rethink a task.

Phase 1 – Planning

The planning phase gets the ball rolling on an RCx project. The main tasks may include:

  • Set project objectives and goals. This can be as simple as addressing one specific problem to organizing a plan to fully commission an entire facility.

  • Agree to team roles and responsibilities. This outlines who the major project stakeholders are and what will be expected of them throughout the RCx process.

  • Perform initial site walk/assessment. The entire RCx team will be on-site for an initial assessment of the facility.

  • Document the Current Facility Requirements. The RCx team along with key project stakeholders from the facility meet to discuss and document the operational needs of the facility.

  • Develop the RCx plan. This should include a description of the facility and its systems, an outline of the scope of work (what is and isn’t included), how deep the investigation will go, detailed steps of the planned RCx process, estimated schedule of project milestones, and desired project outcomes/goals.

  • Perform kick-off meeting and agree to the RCx plan. It is important that the entire project team is part of the kick-off meeting and agree to the RCx plan. This is a crucial part of the process for all projects, but especially large projects. Commissioning in some areas is a new enough service that some involved parties may be unfamiliar with the role of the RCx team and this can cause them to worry or feel threatened by the idea of other people coming into their facility. At our kick-off meetings we are sure to address those concerns ahead of us working in the building. We also continue to alleviate those concerns by communicating with the Owner, Facilities Managers, Maintenance Staff, etc. throughout the entire project.

By the end of the Planning Phase all parties (RCx team, Owner, Facility Managers, Maintenance Staff) involved know their roles and responsibilities in the process. Project stakeholders have approved the timeline and the detailed plan drawn up by the RCx team and the investigation work can then begin.

Phase 2 – Investigation

The investigation phase is when the RCx team gets to work in the facility itself. In this phase the main tasks may include:

  • Collect and review building documents (plans, specs, maintenance logs, equipment lists). This is what allows us to understand the facility in more detail: how the building and its systems are designed to work.

  • Collect energy data and complete energy benchmarking. This critical part of the process allows us to grade the building based on its Energy Use Intensity (EUI). The more utility data available, the better we are able to see how the building consumes energy. This plays a key role in identifying if the building is operating efficiently or drifting over time to a more inefficient state. This also allows us to create a baseline to which we can compare after the implementation phase is complete to verify that our recommendations have had a positive result.

  • Set up and collect trend data from the building automation system for diagnostic monitoring. Here is where we start to see exactly how systems are operating presently. Building automation system trending is one of the most important parts of the investigation phase because we see how systems have operated over time. Through trend data we can see issues that would otherwise be impossible to catch.

  • Interview Maintenance Personnel, Building Operators, and occasionally Occupants. Not only does this step garner valuable data and insight about the facility, it greatly improves buy-in to any operational changes we recommend.

  • Perform functional testing on mechanical systems and equipment. Depending on data collected through interviewing staff and analyzing trends there will likely be questions that can only be answered through functionally testing a building’s systems and components. Only by physically verifying a piece of equipment through onsite point-to-point testing can we be sure that it is operating to meet the operational needs of the facility.

  • Document issues and deficiencies in a master issues log. Any type of commissioning process should have an easy and transparent (to all parties!) way to track issues and who is working on them.

  • Recommend repairs and capital improvements with ROI or energy savings calculations. Interestingly, many of our recommendations are low-cost or no-cost improvements; many can be implemented in-house with little to no costs to the Owner.

  • Deliver a Final RCx Report. This documentation is critical in implementing a plan to save energy or improve how systems operate. We believe that Owners and Facilities Managers need to be able to have the most user-friendly report possible to most efficiently use the information uncovered in our process.

The end of Phase 2 is usually where a Retro-Commissioning project ends. Based on the findings, the Owner is now faced with how to move forward in implementing the reccomendations provided by the RCx team. It takes time to prioritize and plan implementation for the more complex issues identified during the process. For this reason, as well as for the fact that at the start of an RCx project it is difficult to quantify the scope of the implementation phase, the implementation is a separate RCx contract, with the implementation contract written after the Owner has reviewed the findings from the investigation phase.

Phase 3 – Implementation

Our goal with Retro-Commissioning isn’t to just deliver a report, it’s to deliver a better building; this is why implementation is the most crucial phase in the RCx process. There is no point in going through an RCx process if there is no follow through on the back end as the Owner will never see a return on their investment. The Owner and RCx team put an implementation plan together to make repairs to all the issues identified in Phase 1 and 2; then the Owner decides how to proceed based on how much involvement they would like from the RCx team. The amount of involvement the RCx team has during this phase is flexible and project-specific, but usually comes down to one of three options:

  1. A turn-key approach, where the RCx provider oversees all tasks related to the implementation. With this approach the Owner holds one contact with the RCx provider to perform all implementation activites. This means that the RCx provider would be responsible for subcontractors implementing improvements.

  2. Owner and staff perform implementation with the RCx provider there for guidance. When a facility has in-house staff that are highly skilled the need for outside contractors is minimal and the implementation plan and activities are executed in-house with assistance from the RCx team.

  3. The Owner leads all implementation tasks without the assistance of the RCx provider. The Owner may have existing relationships with contractors and have in-house engineers or highly-skilled staff who can work with contractors on implementing and verifying the repairs.

Phase 4 – Verification/Hand-off

At the verification/hand-off phase the RCx provider returns to the site and verifies that all repairs and improvement measures have been completed correctly and wrap up the entire project. Tasks included in this phase may include:

  • Master issues log review. Verify issues identified in the implementation plan have been completed correctly and ensure changes that have been made are thoroughly documented.

  • Create/Update Systems Manual. The systems manual outlines the changes and improvement measures made to the facility’s systems during the implementation phase of the RCx process.

  • Turnover O&M Manual. This outlines how to maintain the improvement measures completed during the implementation phase long into the future.

  • Energy Analysis. Follow up energy analysis if done to ensure the improvement measures are having a positive effect on energy use compared to the original baseline.

The verification/hand-off phase is another crucial part of RCx delivering a better building to the Owner. On-site verification by the RCx team not only provides assurance that all repairs and improvement measures have been done as indicated in the plan, it also provides an opportunity to identify any persisting issues or advise additional measures that would not have been possible prior to implementation.

Due to the ever-increasing complexity of building components, as well as routine wear and tear on equipment, even a well-commissioned building will start to drift from its optimally performing state. Therefore, towards the end of a RCx project, a re-commissioning plan can be put together for the future to ensure continued efficient operation of the building. Re-commissioning is a system-wide analysis done typically every 3-5 years. Due to equipment degeneration, building use changes, and interactions among the mechanical systems, a building will not operate efficiently unless commissioning is an on-going part of the facility. Having a commissioning team return every few years is one option to bring the building operation back in line. However, a more cost-effective option is starting long-term Monitoring-Based Commissioning (MBCx) as soon as a commissioning project is complete. MBCx will prevent the need of re-commissioning as the building won't have the opportunity to drift from the current operational state it is in after implementing repairs. To learn more about MBCx check out our previous blog post “What is monitoring-based commissioning?” on our website.

RCx is a complex process that can be a bit confusing due to the nature of the RCx team looking at the big picture as well as the minute details of each system component. I am excited to share more details and stories about each of the items I touched on here today; but first, my very next post will be WHY RCx is such a great first step for any building that has never been commissioned before. Whether you are watching your utility costs, thinking of replacing equipment, or being driven crazy by an ongoing problem or occupant complaints: RCx provides the data you need to make decisions for your facility. My next post will explain the huge advantage of having an RCx team dig into your facility before you make any costly decisions.

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