Existing Building Services: Retro-Commissioning (RCx)
An existing building systems process for investigating, analyzing, and optimizing building systems performance. Through the implementation of low/no cost and capital intensive Facility Improvement Measures (FIMs) to ensure continued performance. The Existing Building Retro-Commissioning process assists in making the building systems perform interactively to meet the Current Facility Requirements (CFR) and provides the tools to support the
continuous improvement of system performance over time.
Benefits of Retro-Commissioning
Following are some of the key benefits to be realized through retro-commissioning:
- Improved Building Systems Efficiency and Extended Equipment Use Lifetime.
- Improved Occupant Comfort and Productivity.
- Improved Building Operation.
- Documented Building Condition and Deficiencies.
- A List of Recommendations for Improvements.
- A Road Map for Capital Improvements.
- Potentially Reduced Carbon Footprint.
How Do I Know if My Building is a Good Candidate for Retro-Commissioning?
If your building meets any of the following criteria, you will realize a benefit from applying the retro-commissioning process:
- The building was not previously commissioned or re-commissioned.
- There are building systems that seem to have never worked correctly.
- The building has been renovated or has been expanded.
- How the building is used has changed.
- Operating costs have increased rapidly or beyond the rate of energy costs.
- Occupant complaints (too hot or too cold) have increased.
An existing buildings systems ongoing commissioning is a four-step implementation process followed with a step-by-step continuous improvement cycle. Implementing this system within operations is the most important step in creating a smart building. And to achieve a level of excellence, all processes, including the Building Automation System (BAS), must also be analyzed, improved and monitored.
Step 1: Benchmarking
The first step in implementing an ongoing commissioning process is to benchmark the building’s actual performance. This can be done in multiple ways. More affordable solutions consist in utility bill analysis or a detailed building inspection using standard questionnaires such as ASHREA, BOMA, Energy Star® and LEED. These tools can help the team decide what to measure and why. Hardware and software solutions like energy management system (EMS) are also available to monitor energy. If the team needs more data and support, measurement and verification analysis companies (M&V) can be contracted to install measuring devices, collect data and share expertise during the analysis. Although this alternative is more expensive, the team has access to training and the sub-contractor can substantially facilitate the project.
Step 2: Objectives
Once the baseline is settled, the building owner or the management team must establish a first set of objectives to define the vision of the team and the project scope. Then, the team determines the key performance indicators (KPI) to monitor their progression in achieving their objectives.
Step 3: Action
With the project scope and targets defined, the team is able to take action on the building management process and its mechanical systems in order to improve overall building performance (KPI). The most complete solution is to undertake a complete re-commissioning of the building which impacts all the building systems at once in order to reset the building capabilities and start optimization with ongoing commissioning. This solution is more expensive, but can unlock a structure’s full savings potential. As an alternative, the team can also select opportunities from the benchmarking data and take local action on specific equipment to start generating savings.
In order to get more information from the building, fault detection and diagnosis software are powerful tools to analyze the building 24/7 and provide all the required information on where, what and how to improve mechanical system performance in relation with a building’s environment. Accessing this level of information is a critical step to start ongoing commissioning. More and more building managers use energy monitoring applications which give detailed information about daily energy consumption. Although using this software is a good start, they do not provide all the information required to quickly identify any problems in a building’s mechanical system. Without such information, teams are forced to use quick fixes instead of correcting the root cause of the problem. By using a fault detection-based solution instead, problems can be solved more efficiently.
Now that facility managers have more visibility on a building’s performance, investments can be made to buy new sustainable products and equipment to bring the building up to current standards. These asset changes help ensure the building operates as designed and improved.
Step 4: Continuous improvement cycle
To achieve the full benefits of ongoing commissioning, the team has to be involved in a daily effort to improve efforts. Reviewing previously established KPI and taking action at every gap to identify the proper corrective action unlocks the team full potential at reaching operational excellence. Computerized maintenance management software (CMMS) are also useful tools to help the team manage internal activities. Some CMMS also include more advanced business features such as accounting, inventory, project management and budget, which simplify management tasks.
Continuous improvement of maintenance activities is a crucial step in reducing the energy consumption of the building. Implementing a robust preventive maintenance process with efficient scheduling ensures proper monitoring and prevents breakdowns or malfunctions due to excessive wear of equipment. Using CMMS and fault detection tools on a regular basis feeds processes with actions and improvements to implement within a building’s systems. Each problem raised is an opportunity to learn from and gain experience – as well as collect useful data – about a building’s history.
Ongoing commissioning: A management solution
Today’s economy forces companies to do better every day with less or fewer resources. . .
Ongoing commissioning -is a mix of technology and management culture intended to improve building energy consumption during its entire lifecycle.
It’s key to maximizing results and realizing long-term benefits.