What is Retro-Commissioning?
Retro-commissioning is a systematic process of improving the performance of existing building systems. This process addresses problems that have developed throughout a building’s life because of issues such as aging equipment, lack of maintenance, or changes in how occupants use spaces. Retro-commissioning should occur regularly and be part of a long-term operations and maintenance strategy for your building.
How Does the Process Work
Knowing how to plan is the first step! It's important that Cx providers and owners are on the same page and discuss known issues. We'll also do a walkthrough inspection of the facility in this phase.
- Owner selects the Commissioning Agent (CxA).
- Retro-commissioning (RCx) team members are assigned – owner designates an RCx team leader, leader assigns additional responsibilities to staff to support the RCx process.
- CxA performs a walkthrough inspection.
- Owner provides basic building information (project documentation, equipment list, energy bills, etc.).
- The owner team is interviewed and provides a list of known issues.
- Development of the Current Facilities Requirements (CFR) – this document will be continuously updated.
- CxA develops an RCx plan.
The investigative phase is where we uncover deficiencies and decide which fixes and energy conservation measures to use.
- CxA presents RCx Plan.
- CxA reviews all project documentation – equipment list, nameplate information, drawings/specs, as-builts, previous commissioning reports, energy studies, etc.
- CxA reviews the Building Automation System (BAS) and any energy management system to collect trend data and review controls programming, setpoints, graphics, etc.
- CxA develops and witnesses functional testing of equipment specified in RCx plan.
- CxA identifies, describes, and prioritizes energy conservation measures (ECMs), including energy savings calculations and simple payback analysis in an RCx Investigation Report.
This is where we take action! After our careful planning and deliberate investigations, we figure out the best way to apply fixes, install new equipment and get energy conservation measures running.
- Create an implementation plan.
- Develop actionable scopes of work for each ECM, including verification/performance requirements.
- Implement scope of work – replace sensors and actuators, replace worn belts, implement new SOO, change equipment schedules, etc.
As they say, trust but verify. This is the homestretch where we verify that ECMs are working as intended through functional testing. We also train facilities staff on proper maintenance and provide a final Cx report where owners can see the entire process and solutions.
- CxA verifies the successful ECM implementation – functional testing after implementation and collecting data via benchmarking, utility data, and trend data.
- Facilities team gets adequate training to ensure changes are maintained to maximize performance and energy savings.
- CxA develops persistence strategies – ongoing commissioning or recommissioning activities.
- CxA provides a final report.
When You Should Consider It
Retro-commissioning may be suitable for your business if you are:
- Establishing a baseline of your energy performance.
- Looking for energy-saving opportunities for your building and existing equipment.
- If you are having issues heating and cooling your building effectively.
- Managing a building where the occupancy or work function has changed.
- Are experiencing issues with equipment and system performance.
- Noticing unexpected increases in your building’s energy costs and use.
- You are trying to obtain or improve a green building certification for your building.
Benefits of Retro-Commissioning
From a study of 100+ retro-commissioning projects in buildings ranging from 10,000 SF – to 1,000,000 SF by the Lawrence Berkely National Lab (LBNL):
- Electric Savings: 5-15%
- Gas Savings: 1-23%
- Payback Period: 0.2 to 2.1 years
- Median Savings: 45,000 per building
- Max Savings:1.8 million
- Value of Energy Saving: $0.11 – $0.72/SF
- Value of Non-Energy Saving:$0.10 - $0.45/SF
Recent Retro-Commissioning Projects
Kindeva LADBS Retro Cx
Under Los Angeles Municipal Code Division 97, the LA Department of Building & Safety requires buildings over 20,000 SF to provide an Audit and Retro-Commissioning report. Under Kindeva’s planning, the P2S commissioning team is providing an ASHRAE Level II audit and retro-commissioning program for Building #09 (est. 22,000 SF) and the west half of Building #12 (est. 36,000 SF), which are fed from the same electric meter.
LBCC Liberal Arts Campus Bldg V RCx
P2S provided Retro-Commissioning services for the Culinary Arts Building V at the Liberal Arts Campus for LBCC. The building was approximately six years old and had numerous operational issues. This project was recommended to be completed in two phases. The first stage consists of evaluating and diagnosing the various issues in the building. A report will be developed with the findings and recommendations. This phase will also include evaluating existing documents to identify potential design issues. The scope of the second stage will consist of producing construction documents for recommended upgrades/modifications.
SBVC Retro Commissioning
San Bernardino Valley College is looking to reduce energy consumption by retro-commissioning existing mechanical equipment in all buildings tied to the central plant. The P2S Cx services will result in an investigation report including an overview of mechanical systems, field observations, and suggested energy savings opportunities to improve the efficiency of these systems with minimum disruption to the buildings. The retro-commissioning services are based on ASHRAE Guideline 0.2-2015.
M3 & M7 Retro-Commissioning
Northrop Grumman is looking to reduce energy consumption by retro-commissioning existing mechanical equipment in Buildings M3 and M7. This project intends to optimize equipment operations for the current use of the buildings. P2S is tasked to compile an investigation report including an overview of mechanical systems, field observations, and suggested energy savings opportunities to improve the efficiency of these systems with minimum disruption to the buildings.