Retro-commissioning (RCx)
A systematic review and fine‑tuning of existing technical installations to ensure they perform as designed.
Retro‑commissioning (RCx) is a structured way to return existing buildings to their intended performance. In practice, few installations run as designed — sequences get altered, sensors drift, and unnoticed losses accumulate. RCx identifies these deviations and corrects them.
We offer three variants, matched to the building’s complexity, data access, and ambition.
Full RCx
Comprehensive optimisation for durable long‑term savings.
- Mapping of all technical systems against the design intent
- Functional testing of sequences, controls, and interactions
- Measurement and verification of performance before and after
- Detailed action plan with documented savings
Best for complex buildings, portfolios with reporting requirements, or owners who want to evidence full performance over time.
Light RCx (LRCx)
Rapid diagnosis and immediate optimisation.
- Walkthrough of central plantrooms and the BMS
- Identification of the largest, quickest‑to‑implement measures
- Short corrective actions delivered with the operations team
Suitable for buildings that haven’t been reviewed for some time, where a short intervention yields immediate gains. Often the first step before deciding on Full or Tailored.
Tailored RCx (TRCx)
A customised blend of Full and Light, designed for the specific building or portfolio.
- Focused on the systems with the greatest potential
- Combines rapid diagnosis with deeper investigation where it matters
- Adapted to the operations team’s capacity and the building’s operational phase
After RCx
- Documented performance against the design intent
- Recommendations for energy management and continuous follow‑up
- Basis for 3P-garantien, if relevant
RCx is not a one‑off. We recommend a regular review — typically every three to five years — to prevent deviations from building up again.
Questions and answers
What is retro-commissioning?
A structured process that returns an existing building to — or beyond — its intended performance, finding and fixing faults in control logic, sensors and equipment. Few installations run as designed once sequences have been altered and sensors have drifted.
How is it different from operational optimisation?
Operational optimisation tunes setpoints and schedules from operating data. Retro-commissioning is more thorough — it functionally tests sequences and equipment against the design intent and is the right tool when systems have degraded over years.
How much waste can it address?
International studies indicate that over 30% of energy costs in complex buildings are avoidable waste that retro-commissioning can address.
How often should it be done?
Retro-commissioning is not a one-off. We recommend a regular review — typically every three to five years — to prevent deviations from building up again.