Retro-commissioning is becoming increasingly popular in buildings and offshore Oil Production platforms over 5 years of age, in bringing all HVAC systems with tight operating controls and pressure regimes back to an ‘as commissioned’ mode of operation. Checks are carried out on the system controls, water and air flow rates, together with fan and pump performance, to ensure optimum performance and energy efficiency.

Building Commissioning takes the same approach to new buildings. When a building is initially commissioned it undergoes an intensive quality assurance process that begins during design and continues through construction, occupancy, and operations. Commissioning ensures that the new building operates initially as the owner intended and that building staff are prepared to operate and maintain its systems and equipment.
Retro-commissioning is the application of the commissioning process to existing buildings. Retro-commissioning is a process that seeks to improve how building equipment and systems function together. Depending on the age of the building, retro-commissioning can often resolve problems that occurred during design or construction, or address problems that have developed throughout the building’s life. In all, retro-commissioning improves a building’s operations and maintenance (O&M) procedures to enhance overall building performance.
Re-Commissioning is another type of commissioning that occurs when a building that has already been commissioned undergoes another commissioning process.
The decision to recommission may be triggered by a change in building use or ownership, the onset of operational problems, or some other need. Ideally, a plan for recommissioning is established as part of a new building’s original commissioning process or an existing building’s retro-commissioning process.
Re-commissioning is one of improvements. Depending on the project scope, these improvements can range from simple, low-cost fixes to complicated, highly integrated operational measures that are coupled with equipment retrofits. Retro-commissioning is considered successful when a building operates as efficiently as possible, meets the owner’s operating requirements, and includes strategies to ensure benefits last over time.