Retro Commissioning Services
Rising utility bills without a clear cause. Recurring comfort complaints. Sequences that no longer reflect how the building operates. Retro commissioning makes those problems visible and fixes them.
Retro Commissioning Services
ACIS Inc provides retro commissioning services to existing commercial buildings across Dallas, Fort Worth & Houston, a systematic process for evaluating whether building systems are operating as originally designed, identifying deficiencies, and implementing corrections that restore performance and deliver measurable energy savings.
Retro commissioning is one of the most cost-effective energy improvement strategies available to existing buildings. Unlike equipment replacement or major retrofits, retro commissioning works with the systems already in place, uncovering operational problems that have accumulated over time and resolving them through controls adjustments, sequence corrections, and targeted maintenance rather than capital investment.
What Is Retro Commissioning?
Commissioning, when performed on a new building, verifies that installed systems meet design intent before occupancy. Retro commissioning applies the same investigative process to existing buildings, evaluating current system operation against original design documentation, identifying where performance has drifted, and implementing corrections to restore or improve that performance.
The distinction matters because buildings change. Occupancy patterns shift, tenant configurations evolve, equipment ages, control sequences get modified without documentation, and sensors drift out of calibration. What was a well-performing building at commissioning may be consuming significantly more energy than necessary five or ten years later, often without any visible sign of a problem beyond a rising utility bill.
Retro commissioning makes those invisible problems visible and fixes them. Studies consistently show that existing commercial buildings can reduce energy consumption by 10 to 20 percent through retro commissioning alone, without replacing equipment or making capital improvements.
The Retro Commissioning Process
Planning and Document Review
Retro commissioning begins with a review of available building documentation, including original design drawings, sequences of operation, commissioning reports, equipment schedules, and any records of modifications made since original construction. This establishes the baseline against which current performance will be evaluated and identifies systems and sequences that warrant closer investigation.
Site Investigation and Functional Testing
ACIS Inc’s retro commissioning team conducts a systematic site investigation, observing system operation, trending BAS data, testing control sequences, and verifying sensor accuracy across HVAC systems, central plant equipment, and building automation controls. This phase identifies specific deficiencies: sequences that aren’t executing as programmed, sensors that have drifted or failed, control valves that are sticking or leaking, scheduling that doesn’t reflect actual occupancy, and equipment that is running when it shouldn’t be.
Findings and Prioritization
Investigation findings are documented and prioritized based on energy impact, correction effort, and operational risk. Low-cost, high-impact corrections, such as BAS programming adjustments, sensor recalibration, schedule optimization, and setpoint corrections, are typically addressed immediately as part of the retro commissioning scope. Higher-cost findings that require capital investment are documented for inclusion in future planning and capital budgeting.
Implementation of Corrections
ACIS Inc implements identified corrections directly, adjusting BAS sequences, recalibrating sensors, correcting control valve operation, optimizing equipment scheduling, and resolving the operational issues identified during investigation. Our combined mechanical and controls expertise means we can address both the BAS programming side and the mechanical side of most findings without engaging a separate contractor.
Measurement and Verification
Following implementation, ACIS Inc documents the performance improvements achieved, trending BAS data before and after corrections to quantify energy savings and confirm that identified issues have been resolved. This documentation provides a clear record of retro commissioning outcomes and supports ongoing energy reporting and benchmarking.
Common Retro Commissioning Findings
While every building is different, certain deficiencies appear consistently across existing commercial buildings:
- HVAC equipment running outside of scheduled hours: systems conditioning unoccupied spaces
- Simultaneous heating and cooling: reheat operating against cooling in the same zones
- Fixed minimum outdoor air positions: providing more ventilation than occupancy requires
- Chilled water or hot water supply setpoints that haven’t been adjusted seasonally or by load
- VAV boxes that are stuck open, stuck closed, or have failed actuators
- Control sequences that were modified without documentation and no longer reflect design intent
- Drifted or failed sensors providing inaccurate data to the BAS
- Variable speed drives running at fixed speeds, eliminating the energy benefit of the installed equipment
- Cooling tower controls that don’t reset condenser water temperature as ambient conditions allow
- BAS schedules that reflect original occupancy patterns no longer in use
Retro Commissioning and LEED
LEED for Existing Buildings: Operations and Maintenance (LEED O+M) includes retro commissioning as a pathway to Energy and Atmosphere credits. ACIS Inc configures retro commissioning investigations and documentation to support LEED O+M credit requirements, providing the investigation scope, findings documentation, and measurement and verification records that the credit pathway requires.
For facilities pursuing LEED certification or recertification, retro commissioning delivers both the performance improvements and the documented evidence that the certification process demands.
When Retro Commissioning Is the Right Starting Point
Retro commissioning is most appropriate for facilities where:
- Energy costs have increased without a clear explanation
- Comfort complaints are recurring despite no obvious mechanical cause
- The building has not been commissioned or recommissioned within the last five years
- Significant tenant or occupancy changes have occurred since original commissioning
- BAS sequences have been modified over time without documentation
- The facility is evaluating a capital improvement project and wants to understand baseline performance first
- LEED O+M certification or recertification is being pursued
The ACIS Inc Advantage — Mechanical and Controls Under One Roof
Retro commissioning findings frequently span both controls and mechanical systems. A BAS sequence problem may have a mechanical root cause. A mechanical issue may require a controls solution. Contractors who can only address one side of the equation deliver incomplete retro commissioning outcomes.
ACIS Inc brings combined HVAC and building automation expertise to every retro commissioning engagement, diagnosing and correcting both the controls and mechanical dimensions of identified deficiencies without handoffs between separate contractors. This integrated capability is what makes retro commissioning with ACIS Inc deliver results that hold.
Why Facilities Choose ACIS Inc for Retro Commissioning
- Combined mechanical and BAS expertise, addressing findings on both sides
- Open-source platform capability, including Tridium Niagara, Distech, Honeywell WEBs, and Johnson Controls FX
- Systematic investigation process with documented findings and prioritization
- Direct implementation of corrections, with no handoff to a separate contractor
- Measurement and verification to quantify and document energy savings
- LEED O+M retro commissioning documentation support
- Active in the Dallas, Fort Worth & Houston market with 24/7 support availability
Contact ACIS Inc to discuss retro commissioning for your Dallas, Fort Worth & Houston facility and schedule an initial site assessment.
